Bestsound™ Technology

Transcript

BestSound Technology Compendium Content Innovations for more than 130 years 4 BestSound Technology 6 Better Hearing 8 Restoring audibility 10 AGCi & AGCo 10 Adjusting gain, compression and MPO in Connexx 11 Improving speech intelligibility in noise 12 Directional microphones 12 SpeechFocus 12 Soft Level Directivity 14 Adjusting microphone settings in Connexx 16 SpeechFocus – How to demonstrate 18 Bypassing noise & reverberation with e2e wireless 2.0 20 Adjusting wireless connections in Connexx 23 Sound Comfort 24 Performance levels 62 Eliminating feedback 26 Explaining performance levels to users 64 FeedbackStopper 27 Speech understanding in quiet 67 Evaluation of FeedbackStopper 30 Speech understanding in noise 68 Fine-tuning the FeedbackStopper in Connexx 32 Listening to TVs 69 FeedbackStopper – How to demonstrate 33 Using the phone 70 Suppressing unwanted noise 34 Listening to music 72 Speech Enhancement & Noise Reduction 34 SoundSmoothing 36 Best Fitting 74 eWindScreen 37 ConnexxLink: Wireless programming interface 76 Fine-tuning noise suppression in Connexx 38 Prescriptive fitting: NAL-NL2 & ConnexxFit 78 Noise suppression – How to demonstrate 40 AutoFit: Match to target with a click of a button 80 Optimizing localization 42 Counseling & Training 82 Binaural synchronization via e2e wireless 2.0 42 Real Time Display 82 TruEar 43 Hearing Loss Simulator 83 TruEar & e2e wireless 2.0 in Connexx 45 eARena 84 Extending bandwidth 46 SoundBrilliance 46 A final word 86 SoundBrilliance – Settings in Connexx 48 SoundBrilliance – How to demonstrate 49 Abbreviations 87 References 87 Individuality 50 Situation-specific learning with SoundLearning 2.0 52 Situation Detection 56 Managing SoundLearning 2.0 in Connexx 58 SoundLearning 2.0 – How to demonstrate 61 Innovations for more than 130 years 1878 1878 Phonophor Siemens develops the first technical solution for hearing loss. 4 1910 1910 First line of hearing instruments Siemens begins the first serial production of hearing instruments. 1959 Auriculina 326 Siemens launches its first BehindThe-Ear hearing instrument. Back in 1878, Werner von Siemens, the founder of Siemens, long-standing innovative power of Siemens is also reflected invented a special telephone receiver for his hearing-impaired in the number of patents owned. In the past ten years, wife. Ever since then, the engineers and scientists at Siemens Siemens filed more patents than any other hearing instru- have continued to develop innovative solutions to help the ment manufacturer. hearing-impaired. As the following timeline makes clear, Siemens has been in the forefront of hearing instrument In fact, just in the past two years, Siemens filed more than technology since the beginning. twice as many patents than any other competitor. Clearly, Siemens is the sustained innovation leader in the hearing In the past 5 years alone, Siemens introduced to the world instrument industry. several innovations, many of them copied by other manufacturers, and some of them still unrivaled in the industry. The 1959 1966 Siretta 336 Siemens presents the first In-The-Ear hearing instrument. 1966 1997 Prisma Siemens introduces the first digital hearing instrument featuring a directional microphone. 1997 2004 AcurisTM Siemens introduces the first wireless system e2e wirelessTM which is also available for CICs. 2004 2008 2008 Siemens TekTM Siemens introduces a revolutionary wireless enhancement system giving wearers unprecedented access to all favorite audio devices. 5 BestSound Speech Focus Feedback Stopper Better Hearing Requirements of hearing instrument wearers and the innovative solutions offered by BestSound Technology Sound Comfort Individuality Sound Learning 2.0 6 Technology The BestSoundTM Technology with its three FeedbackStopper facilitates the optimum key innovations is the latest contribution to a Sound Comfort. FeedbackStopper achieves long list of developments Siemens has brought effective feedback suppression by combining to the market. These three key innovations the proven Acoustic Fingerprint Technology include SpeechFocus, FeedbackStopper, and with a new Transient Frequency Shift, elimi- SoundLearning nating feedback before it is even noticed by TM 2.0 are briefly described as follows. the user. SpeechFocus continuously analyzes the en- SoundLearning 2.0 is the most sophisticated vironment for the most favorable speech- learning algorithm on the market which best to-noise ratio, and automatically selects the adapts to the user’s individual preferences. microphone configuration which has the Automatically steered by an intelligent acoustic potential to offer the best speech intelligibility situation detector, SoundLearning 2.0 allows for the user, regardless of whether speech is the user to teach preferred gain, compression, coming from the front, behind, or the side. and frequency shape independently for various acoustic situations. 7 Better Hearing 8 Better Hearing Better Hearing, first of all, means that a hearing instrument should restore the audibility of sounds. Secondly, and more importantly for hearing instrument users, Better Hearing is not just hearing, but Sound Comfort also the ability to understand speech, especially in noisy situations. To restore audibility, BestSound Technology employs multichannel automatic gain control for both a wide range of input signals, and for controlling the maximum output (AGCi and AGCo). To improve speech intelligibility in noisy situations, directional microphones and wireless Audibility AGCo BestSound Technology´s feature set for Better Hearing Performance AGCi Individuality connections (e2e wirelessTM 2.0, T-coil) are used. Directional microphone SpeechFocus Soft Level Directivity e2e wireless 9 Best Fitting Speech intelligibility Restoring audibility AGCi & AGCo Siemens hearing instruments offer up to 16 patient’s residual dynamic range so that soft channels of compression (AGCi) (Figure 1). sounds are audible, average sounds are In combination with wide dynamic range comfortable, and loud sounds are tolerable, multichannel input compression, an intelligent AGCo also is required to guarantee that everyday sounds are not uncomfortably loud. Because UCL varies across frequency, AGCo 0 also needs to be multichannel to be effective. 20 In addition, broadband signals are perceived as louder than narrowband signals due to the Vowels 40 Level / dB HL Figure 1 Note how the dynamic range becomes smaller as the hearing loss becomes more severe, illustrating the need for multichannel compression to map speech into the patient’s residual dynamic range. To precisely map real-world sounds into every loudness summation effect. So to ensure that 60 the patient’s dynamic range is utilized to the 80 fullest without exceeding any uncomfortable Consonants levels, Siemens offers a multichannel band100 width-controlled AGCo that guarantees a comfortable level of loudness to an equal extent 120 125 250 500 1k 2k 4k 8k Frequency / Hz Normal hearing Audible Inaudible Hearing loss UCL 10 for narrowband and broadband sounds. Better Hearing Adjusting gain, compression and MPO in channels of compression. Depending on the kneepoint, ratio, and time constant. To make fitting formula and acclimatization level the fine-tuning process more efficient, channels selected, the First Fit algorithm automatically can be combined into handles (a grouping of sets the master gain as well as the compres- adjacent channels), and level-dependent gain sion kneepoints and ratios to achieve the best is also adjustable separately. For instance, by possible match to the selected fitting formula clicking the “gain for soft sounds” controls, for a wide range of input levels. Nevertheless, gain and compression thresholds are automat- to offer the Hearing Care Professional maxi- ically adjusted accordingly. Individuality has an independently adjustable compression mum flexibility, every compression channel Performance Figure 2 Compression and gain controls in Connexx fitting software 11 Best Fitting Siemens hearing instruments offer up to 16 Sound Comfort Connexx Improving speech intelligibility in noise Directional microphones Directional microphone technology is the only speaks. A similar situation is when the hear- feature proven to enhance speech intelligibility ing instrument user is walking side by side in difficult environments. One widely recog- with the speaker. In such cases, speech does nized limitation of directional microphones is not originate from the front, but the hearing that they can only focus to the front of the user. instrument wearer cannot turn to look at the In real life, however, speech does not always speaker either. An ideal microphone system occur from the front. One such specific, but therefore should be able to steer maximum commonplace, situation is when the user is directivity toward speech, regardless which driving a car and a passenger in the backseat direction it originates. SpeechFocus SpeechFocus is the key feature in BestSound originate from the front. SpeechFocus contin- Technology that overcomes the limitations uously scans sounds in the listening environ- of traditional directional microphones. In ment for speech patterns. When speech is addition to having all the functionalities of a detected, then SpeechFocus selects the direc- four-channel adaptive directional microphone, tivity pattern most effective in focusing on when necessary, SpeechFocus is able to auto- that speech source. matically focus on speech which does not 12 greatest output for speech is then chosen as omnidirectional, adaptive directional, and a the appropriate microphone mode. This means reverse directional pattern. Unlike typical that when speech is detected from the front directional microphone patterns, which only hemisphere, the adaptive directional micro- attenuate sounds coming from the sides and phone is employed, reducing noise from the the back, this backward directional microphone side and the back. When speech is detected as pattern works like an acoustic rearview mirror originating from the back, the backward direc- and focuses on speech which originates from tional microphone pattern is selected. When the back while suppressing noise from the speech is detected directly from the left or the front. The signals from all directivity patterns right side, then the omnidirectional directivity are continuously analyzed for speech patterns. pattern is engaged (Figure 3). Better Hearing neously three different directivity patterns: Sound Comfort The microphone pattern which results in the Individuality SpeechFocus works by operating simulta- Performance Figure 3 Illustration of how SpeechFocus analyzes the input signals from three directivity patterns for effective steering Acoustical environment 13 Best Fitting SpeechFocus Analyzer omnidirectional microphone when speech in a study with 20 experienced hearing in- originated from the back (Figure 4). This result strument wearers. Results showed an approx- was also confirmed in the real world when the imately 10 dB SNR advantage (p <0.001) for subjects preferred SpeechFocus over traditional SpeechFocus over the conventional directional directional microphones after a home trial microphone and 5 dB improvement over the (Branda & Hernandez 2010). 2 0 -2 -4 SRT / dB Figure 4 Study shows that in a situation where speech originates from behind the user, SpeechFocus offers approximately 10 dB SNR advantage over traditional directional microphones. The effectiveness of SpeechFocus was validated -6 -8 -10 -12 Directional Omni SpeechFocus Microphone mode Soft Level Directivity 14 Another widely recognized limitation of tradi- noise, directional microphones themselves tional directional microphones is the fact that are noisy. As a result, the typical implemen- while their primary function is to suppress tation is that directional microphones are between 50 and 60 dB SPL. This prevents the phones can be activated at a much lower noise user from hearing the amplified microphone level. The extent of this directivity, however, noise that can be louder than the noise in the is dependent upon the noise level so that the environment. Even at this setting, directional softer the noise level, the less directional the microphone noise can still be problematic for microphone is. The advantage of such a noise some users who have good low-frequency level-dependent directivity is that when the hearing. Because of these higher noise levels microphone is less directional, the microphone from traditional microphones, often users can noise is also softer. In effect, the microphone only take advantage of directionality when noise is always less than the ambient noise, the noise level of the listening situation is and the user can take advantage of directivity relatively high. BestSound Technology’s direc- and achieve better speech intelligibility even in tional microphone system features a Soft Level low-noise situations. Better Hearing With Soft Level Directivity, directional micro- Sound Comfort floor exceeds a certain loudness level, usually Individuality Directivity that overcomes this limitation. Performance Figure 5 Soft Level Directivity enhances directional microphone benefit for soft levels. 15 Best Fitting engaged automatically only when the noise Adjusting microphone settings in Connexx SpeechFocus is offered as a separate direction- his or her head to face the speaker. Directional al microphone setting under the Microphone/ (Adaptive) should be selected for very noisy Bluetooth tab. It is the default setting in the environments, and the Omnidirectional micro- dedicated “SpeechFocus” program. We also phone should be used for music and outdoor recommend it to be used when setting up pro- programs, as well as in a mixed input mode, grams for use when speech may come from such as with DAI or Tek Transmitter. different directions but the wearer cannot turn Figure 6 Fine-tuning options for the microphone system in Connexx 16 of Soft Level Directivity, and to fine-tune its system by means of the checkbox “Speech in function, it is possible to adjust the Activation noise only”. When this box is checked, the Threshold at which the microphone switches directional microphone will be activated only from the omnidirectional to directional mode. if the current acoustical situation is “speech in This is the level that the environmental noise noise”. If the checkbox is unchecked, the direc- has to reach before the directional microphone tional microphone is activated additionally in is activated. The three threshold settings are: situations when “noise only” (no matter which 48, 54, and 60 dB SPL. The default setting is kind of noise) is detected. Note that regardless 54 dB SPL, which is preferred by most patients. of the setting of the checkbox “Speech in noise A threshold of 48 dB SPL would be for some- only”, the situation detector always deactivates one who requires more directivity in low-level the directional microphone when music or noise. The highest settings of 60 dB SPL would speech in quiet is detected. It is recommend- be selected for patients who prefer the omni- ed that “Speech in noise only” is checked when directional mode in most situations and for it is important for the patient to hear soft envi- those who have a greater need to hear envi- ronmental sounds. Better Hearing ation detector on the automatic microphone Sound Comfort the Universal program. To take full advantage Individuality It is possible to adjust the effect of the situ- Performance ronmental sounds at average levels from all directions. To use the same Automatic/TruEar mode setting as in Connexx 6.3, select 54 dB as the activation threshold. 17 Best Fitting Automatic/TruEar mode is the default option in >> SpeechFocus – How to demonstrate SpeechFocus can be demonstrated using the SpeechFocus will be engaged and the green Connexx Real Time Display. The diagram re- field will indicate where speech is detected presents an aerial view of the hearing instrument and where directionality is focused. The two o wearer facing front (0 azimuth). Depending speakers will automatically alternate playing on the direction from which speech originates, the speech and noise signal. When speech the green field indicates the focus of directivity. comes from the front, the green field will Have the user wear the instrument so that focus to the front of the user, indicating that he or she can hear as well as see the effects traditional directional microphone is engaged. of SpeechFocus. Play the provided sound file When the noise is coming from the front and utilizing two loudspeakers. Position the loud- the speech is coming from the back, the re- speaker playing speech in front of the user and verse directional microphone will be activated the loudspeaker playing noise behind the user. and the green field will appear behind the user (Figure 7). To demonstrate how the hearing instruments switch to omnidirectional mode when speech comes from the side, move the speakers to either side of the user. In this case, the green field will surround the user. Since the hearing instrument cannot determine exactly which side speech originates, the speaker figure will alternate on either side of the user. 18 Performance << 19 Best Fitting Individuality Sound Comfort Figure 7 Demonstrating SpeechFocus with the Real Time Display Better Hearing Bypassing noise & reverberation with e2e wireless 2.0 Even more efficient than directional micro- BestSound Technology is equipped with phones in improving speech intelligibility in e2e wireless 2.0 and is thus compatible with reverberant and noisy environments, wireless the Tek system. This technology allows the connections bypass ambient noise by picking Siemens Tek Connect remote control to employ up the “clean” target signal and transmitting it Bluetooth functionality and be compatible directly into the hearing instruments. with a wide variety of modern communication devices – even for CICs (Figure 8). For phones that do not support Bluetooth functionality, such as many landline phones, Siemens offers a Phone Adapter (PA) which can be plugged into the landline phone. The PA converts the telephone signal to a Bluetooth signal that can be received by the Tek Connect remote control. With the Tek Transmitter, signals from any stereo or TV set can be received in stereo and without audible delay. 20 Better Hearing Sound Comfort e2e wireless 2.0 Individuality Phone Adapter Phone / Mobile Music Television Performance Tek Connect Phone 21 Best Fitting Figure 8 Connectivity options with Tek 22 which can have the effect of improving the intelligibility on the phone because of several SNR by 2 dB. And, of course, listening with two reasons. It bypasses noise in the listener’s ears assures that the better ear is always in- environment and offers a better acoustic cluded. In fact, recent research has shown that coupling than with microphone. Listening with listening on the phone with both ears im- both ears allows the user to take advantage of proves the SNR by more than 5 dB (Ricketts & binaural redundancy and central integration Picou 2009) (Figure 9). 6 5 Binaural benefit / dB SNR Figure 9 Study shows that in the wireless-only condition where the user is only listening to the telephone signal, binaural listening offers more than 5 dB improvement in SNR. In the wireless-plus-microphone mode where the telephone signal is mixed with the environmental sounds, the improvement is also more than 4 dB. Tek with e2e wireless 2.0 improves speech 4 3 2 1 0 Wireless only (”clean“) Wireless + mic (”mixed“) Better Hearing Adjusting wireless connections in the wireless and the microphone signal can be the hearing instrument’s microphone signal adjusted independently. according to the patient’s needs. The levels for Performance Individuality Figure 10 Fine-tuning options to set up wireless connections in Connexx 23 Best Fitting Connexx allows mixing the wireless signal with Sound Comfort Connexx Sound Comfort 24 Better Hearing The auditory deprivation caused by gradual hearing loss makes it difficult for many users to accept amplification immediately. This is one reason why first-time users often complain that everything sounds too loud or Sound Comfort too shrill. This is also one of the reasons why many hearing instruments end up “in the drawer”. In order for customers to become acclimatized to amplification, wearing new hearing instruments must be comfortable, not only physically, but also in regard to sound quality. First-time users typically appreciate any means to suppress unwanted noises since they Individuality experience the most difficulties in noisy situations. Experienced wearers, however, know that besides noise reduction, feedback suppression, bandwidth extension, and restored localization are also important means to improve sound comfort (Kochkin 2005). FeedbackStopper Suppress unwanted noise SoundSmoothing BestSound Technology’s feature set for Sound Comfort eWindScreen Optimize localization e2e wireless Extend bandwidth SoundBrilliance TruEar 25 Best Fitting Eliminate feedback Performance Speech and Noise Management Eliminating feedback Acoustic feedback is one of the most negative While most currently available feedback man- aspects associated with hearing instruments. agement systems are able to account for individ- In many cases, the annoyance and embarrass- ual ear and fitting differences, and counteract ment caused by feedback may even outweigh the static feedback path, the challenge lies in an individual’s perceived benefit of amplifica- rapidly changing feedback paths. Even for the tion. Feedback occurs when amplified sound same person, no matter how well an earmold from the receiver leaks out of the ear canal or in-the-ear hearing instrument fits in the (e.g. through a vent), is picked up by the micro- canal, as the user goes about in his daily life, phone, and in turn amplified again. The route the feedback path changes when he talks or the amplified signal travels back to the micro- chews, when he leans his head back against the phone is called the feedback path. The goal, couch, or when he hugs a loved one. Changes therefore, is to break this feedback path. With in the feedback path, such as those just men- BestSound Technology, Siemens introduces the tioned, occur very quickly. In order to eliminate new FeedbackStopper which provides the most feedback in these situations before it becomes efficient protection against acoustic feedback, disturbing to the user, it is essential that the even in the most critical situations. Effective feedback canceler acts within milliseconds. feedback suppression is so fundamental and A potential downside, however, is that fast-acting essential in a hearing instrument that the new feedback cancelation systems often mistake FeedbackStopper is featured in all products tonal stimuli in the environment such as music equipped with BestSound Technology. for feedback, and thereby create artifacts and distortions in such acoustic situations. In summary then, a good feedback cancelation must fulfill three requirements: 26 Better Hearing Requirements Sound Comfort Suppress feedback No artifacts Individuality Fast reaction Siemens’ powerful FeedbackStopper is an shifting. Briefly shifting the entire output of adaptive phase cancelation system combined the amplifier by 25 Hz breaks the feedback with Transient Frequency Shift. The adaptive loop and therefore helps to suppress feedback. phase cancelation filter effectively cancels But even more importantly, the frequency shift feedback by continuously estimating the feed- helps to avoid artifacts. This is because the back path and generating a corresponding out- adaptive filter is more likely to generate arti- of-phase signal. Thus, feedback is suppressed facts if external signals are similar to the feed- without reducing gain for external signals like back signal. By shifting the frequency of the speech, music, and environmental sounds. feedback signal, it becomes less similar to the This adaptation process can be achieved ex- external signal so that the adaptive filter can tremely quickly due to transient frequency react extremely quickly without generating Performance FeedbackStopper 27 Best Fitting Figure 11 Requirements for Feedback Cancelation algorithm. artifacts. This small frequency shift may be and non-feedback situations, FeedbackStopper perceived by some listeners as a slight “rough- employs the Siemens-patented Acoustic ness” in sound quality, however, the brief Fingerprint Technology (AFT). Similar technol- roughness is much less audible or annoying ogies are used in audio coding and referred than the whistling of feedback. to as “digital watermarking.” With AFT, the amplified signal that leaves the hearing instru- Absolute freedom from artifacts can only be ment receiver is slightly phase-modulated and achieved if the adaptation is stopped and if the this “tag” or “fingerprint” is used to identify frequency shifting is switched off. To maximize signals that have already been amplified by the listening comfort, therefore, FeedbackStopper hearing instrument (i.e. feedback potential). completely halts adaptation and frequency It has been demonstrated in psychoacoustic shifting whenever there is no feedback risk. experiments that this phase modulation tag is To distinguish between feedback situations inaudible to the human ear. It can, however, be identified by a technical modulation detec- Figure 12 How FeedbackStopper works Acoustic fingerprint is detected tor and used as a critical piece of information which tells the FeedbackStopper when to activate frequency shift and adaptation. No feedback Feedback possible Freeze adaptation of phase canceler Fast adaptation of phase canceler Frequency shift off Frequency shift on f Acoustic fingerprint is not detected 28 Figure 13 summarizes the technologies Stopper works. Once the acoustic fingerprint used by FeedbackStopper to fulfill the three is detected (e.g., feedback is likely to occur), main requirements on effective feedback FeedbackStopper briefly shifts the entire cancelation systems. Better Hearing Figure 12 illustrates how the new Feedback Sound Comfort output of the amplifier by 25 Hz. As soon as feedback is suppressed and the fingerprint is no longer detected in the incoming signal, the FeedbackStopper switches off frequency shifting and completely freezes the adaptation in FeedbackStopper Suppress feedback Phase Cancelation No artifacts Acoustic Fingerprint Technology Fast reaction Transient Frequency Shift Performance Requirements 29 Best Fitting Figure 13 Requirements and solutions for feedback suppression Individuality order to avoid artifacts. Evaluation of FeedbackStopper To evaluate this new technology, Feedback quency shifting. The “med” setting also em- Stopper was tested in a study which replicated ploys frequency shifting, but with a slower real-world conditions (Branda & Herbig 2010). adaptation speed of the phase canceler. On Twelve hearing-impaired subjects with moder- average, added stable gain of 24.5 dB is ately sloping hearing loss listened to babble achieved with the FeedbackStopper in “fast” noise presented at 50 dB SPL while moving (and Open Optimizer activated). This clearly their heads, chewing, and talking. Added stable exceeds the needed margin for variations of gain provided by FeedbackStopper with and the feedback path in real-world listening for without frequency shift was measured.The the majority of hearing instrument wearers. results showed significant (p < 0.01) improvements of 7 dB for the FeedbackStopper with frequency shifting activated (setting “fast” in Fig. 16) compared to a setting with the same phase cancelation setting but without fre- 30 28.0 27.0 26.8 24.8 23.0 20.5 20 15.3 21.5 20.5 17.5 15 24.5 17.8 Sound Comfort 25 Better Hearing 30 Added stable gain / dB 19.0 16.0 13.0 10 5 0 Medium Fast Individuality Slow FeedbackStopper setting Since open-canal fittings are the most challeng- stable gain of Pure and Life open-canal fittings ing for feedback stability, the Open Optimizer can be increased by 4 dB in noisy environ- featured in Pure and Life instruments improves ments and 7 dB in quiet listening situations. the effectiveness of FeedbackStopper. This is Hence, for fittings with closed and open achieved by optimizing the parameterization domes/tips and vents larger than 2.5 mm, of the signal processing on specific properties Open Optimizer should be activated in order of the acoustic feedback path of open-canal to achieve maximum feedback stability. Performance Open Optimizer fitting. By activating the Open Optimizer, the 31 Best Fitting Figure 14 FeedbackStopper with transient frequency shifting and fast phase cancelation provides ~25 dB added stable gain in dynamic situations. Fine-tuning the FeedbackStopper in Connexx FeedbackStopper has three settings: shift activation so that shifting occurs only • Slow setting: Fast feedback suppression when absolutely necessary. This is the without frequency shift. This setting is optimized for maximum sound quality and a more sensitive frequency shift activation so less prone to feedback and more disturbed by that the shift occurs more often. This setting the roughness in sound quality introduced should be used for individuals more prone to by frequency shift. feedback and not as bothered by occasional which features a less sensitive frequency 32 • Fast setting: Fast feedback suppression with should be chosen for individuals who are • Medium setting: Fast feedback suppression Figure 15 Open Optimizer is automatically activated by First Fit except for custom earmolds with vents smaller than 2.5 mm. default setting. roughness in sound quality caused by frequency shift. Better Hearing Preferably, use an open fitting, attach it to the with the hearing instrument either in the model ear and fit the device to moderately patient’s ear, or on a model ear. When de- sloping hearing loss. Switch off the Feedback monstrating FeedbackStopper on the patient’s Stopper and reduce the gain until no whistling ear, set the FeedbackStopper to OFF with the is audible. Then, switch on the FeedbackStopper hearing instrument at “use gain”, and slowly and increase the gain (either in Connexx or approach the hearing instrument with an open with a VC) until whistling is audible. The dif- hand. Note the distance between the hand and ference between these two gain settings is the hearing instrument when feedback first the so-called “added stable gain” and usually occurs. Next, set the FeedbackStopper to the amounts to about 25 dB. Individuality The FeedbackStopper can be demonstrated Sound Comfort How to demonstrate Fast setting. Note how much closer the hand can be to the hearing instrument before feedback occurs, indicating that the FeedbackStopper Performance can effectively eliminate feedback even in the most critical situations. When using a model ear, added stable gain can be demonstrated. << 33 Best Fitting >> FeedbackStopper – Suppressing unwanted noise One of the common needs of hearing instru- ensure that speech remains intelligible while ment users is to understand speech despite noise is reduced. BestSound Technology em- different kinds of background noise. That ploys dedicated signal processing schemes to means that hearing instruments need to be suppress stationary noise, noise during speech, able to distinguish different kinds of noises so impulsive noises like doors slamming, wind that appropriate strategies can be applied to noise, and microphone noise. Speech Enhancement & Noise Reduction Siemens’ Speech and Noise Management sys- continuously estimates the noise level in the tem comprises of a slow, modulation-based incoming signal. This is a very fast-acting algo- algorithm called Noise Reduction and a rapid rithm that works well to attenuate noise during Wiener filter called Speech Enhancement. speech – even between syllables. Neither of Noise Reduction works by actively detecting the algorithms affects speech-only situations. speech modulations in the input signal. When The fact that both strategies are multichannel speech is not detected, then the signal is cate- and adaptive means that different noises with gorized as noise and is reduced. This strategy different frequency content can be addressed is most effective in noise-only situations. In simultaneously. Speech Enhancement, the hearing instrument 34 Better Hearing Noise Speech and noise Performance Speech Enhancement 35 Best Fitting Noise Reduction Individuality Sound Comfort Figure 16 Two types of noise reduction working simultaneously: effects of slow-acting Noise Reduction (left) and fast-acting Speech Enhancement (right) SoundSmoothing Figure 17 Speech interspersed with clattering dishes, with SoundSmoothing off (left panel) and on (right panel). With SoundSmoothing on (right), the sudden impulse sounds of the dishes are significantly attenuated while speech is preserved. 36 Research has shown that 33% of background (e.g., clinking of dishes, placing items on hard noise is transient in duration, and that for surfaces, etc.). SoundSmoothingTM is a highly hearing instrument users, this type of noise is sophisticated algorithm specifically designed rated nearly as annoying as other noise types to reduce the annoyance of these impulsive with longer durations (Hernandez et al. 2006). noise signals without affecting the spectrum Such sounds occur in many everyday activities of speech signals (Figure 17). SoundSmoothing off SoundSmoothing on Better Hearing signals are correlated. However, when there is blows across the microphones, the resulting wind blowing, because of the turbulences set noise can be loud and distracting, preventing up by the wind within the microphone port, them from enjoying golfing, a cycling trip, or a the two signals are different and not correlated day at the beach. In order to reduce wind noise, (Figure 18). So when uncorrelated signals Siemens eWindScreen are detected, eWindScreen is activated. In the TM presence of wind, eWindScreen switches to effects. This is accomplished by using two mi- the omnidirectional microphone mode and crophone signals. In a typical listening situation, reduces the output level of frequencies below when speech arrives at two microphones, the 1 kHz by up to 30 dB. Speech BestSound Technology now also offers eWind Screen for single-microphone instruments such as CICs. In this configuration, the situati- 0 on detector is extended to classify wind based -0.1 on the typical fluctuating spectral properties -0.2 Performance x(t) 0.1 of wind noise. When wind is detected, the gain Wind 0.2 in frequencies below 1 kHz is reduced. As wind 0.1 noise usually is only an issue for CIC wearers in 0 very windy situations, the single-microphone -0.1 wind noise reduction will apply attenuation for -0.2 wind speeds above 15 km/h. 0 10 20 30 40 50 60 70 80 90 100 t / ms 37 Best Fitting Microphone 1 Microphone 2 presence of wind and reduces its distracting 0.2 x(t) Figure 18 Speech and wind signals arriving at the two microphones. On the top, speech signals arriving at the two microphones are correlated while on the bottom, wind generates turbulence at the microphone ports and results in signals that are not correlated. actively detects the Individuality For hearing instrument users, when wind Sound Comfort eWindScreen Fine-tuning noise suppression in Connexx Speech and Noise Management SoundSmoothing The specific behavior of the different algo- There are three different settings for rithms of the Speech and Noise Management SoundSmoothing: can be fine-tuned in seven different steps with • Min: SoundSmoothing is set to -20 dB the “Max” setting representing the strongest attenuation of impulsive sounds with a noise attenuation. Additionally, by the use of 60 dB SPL kneepoint. the checkbox, the feature can be deactivated. • Med: SoundSmoothing is set to -30 dB The “Tooltip” shows the range for the effective- attenuation of impulsive sounds with a ness of the Speech and Noise Management. 50 dB SPL kneepoint. After First Fit, a medium setting of the Speech • Max: SoundSmoothing is set to -40 dB and Noise Management is selected. This setting attenuation of impulsive sounds with a achieves high listening comfort and very good 40 dB SPL kneepoint. speech intelligibility for most hearing-impaired “Med“ is the recommended setting and also listeners. By selecting multichannel view, the the default setting after First Fit. user can have even more flexibility and adjust the effectiveness of the noise attenuation in eWindScreen four channels independently in four steps: off, Besides certain programs such as music, min, med, and max. The checkbox “Speech in eWindScreen is activated in most programs by noise only” allows to adjust the effect of the default. eWindScreen can be deactivated by situation detector on the Speech and Noise unchecking the corresponding box under the Management – in the same way as for the Sound Management tab. automatic microphone system. 38 Better Hearing Sound Comfort 39 Best Fitting Performance Individuality Figure 19 Fine-tuning options for BestSound Technology’s noise reduction techniques >> Noise suppression – How to demonstrate The Real Time Display in the Connexx fitting When speech and noise are present, the bars software can be used to demonstrate the move up and down much quicker, illustrating effects of noise reduction features. Under the the effects of reducing the small pockets of Noise Reduction page, the fluctuating bars noise in between words and syllables. This is indicate the amount of gain reduction in each to assure that speech intelligibility is main- gain channel. Depending on the type of noise tained as well as ease of listening and listening that is introduced to the hearing instrument, comfort. Note that there is also some reduction the user will be able to observe how appropri- in quiet visible, as microphone noise also is ate gain reduction is applied. When only sta- attenuated in this case. To demonstrate tionary noise is played, the hearing instrument SoundSmoothing, simply clap your hands or activates a gradual channel-specific reduction tap a pen against a table or glass. All the bars in gain. This is maintained in order to ensure will instantaneously reach down to the bottom listening comfort while noise is present. of the graph, illustrating the dramatic reduction in gain to make sure that these sounds are not too startling or annoying for the user. Use a fan or blow across the microphone ports of the hearing instrument to show the effects of eWindScreen. In this case, the bars in the low frequencies will drop. 40 Better Hearing Sound Comfort << 41 Best Fitting Performance Individuality Figure 20 The Noise Reduction page of the Real Time Display allows the Hearing Care Professional to demonstrate various noise reduction algorithms. This example is for street noise, which shows the effects of both the modulation-based noise reduction and the fast-acting Wiener filter. Optimizing localization Localization is dependent on spectral differences, ation, however, the determining factor is the interaural time differences, and interaural monaural high-frequency spectral cues that level differences for left-versus-right discrim- are shaped by the pinna. To optimize localiza- ination. Thus, synchronization of left and right tion for all dimensions, therefore, BestSound hearing instruments is required to ensure good Technology employs binaural synchronization left/right discrimination (Powers & Burton via e2e wireless 2.0 to maintain left-right 2005). For localization of elevation (above or localization, and TruEarTM to improve front- below ear level) and for front/back differenti- back discrimination. Binaural synchronization via e2e wireless 2.0 The Siemens e2e wireless 2.0 system enables instruments, maintaining symmetrical function the right and left hearing instruments to work and optimizing day-to-day user efficiency (e.g., together in a harmonized system. The input ob- only one button has to be pushed to adjust both tained from both instruments is shared so that instruments). Studies with this technology have important decisions concerning signal proces- shown that synchronized microphones are re- sing are based on this combined intelligence, quired for good localization (Keidser et al. 2006) allowing for symmetrical steering of functions and that the majority of subjects prefers linked such as digital noise reduction and directional hearing instruments in the real world (Smith et technology. User commands regarding volume al. 2008). control adjustment and program selection are also transmitted wirelessly between hearing 42 Better Hearing Besides binaural hearing (e.g., analysis and solves this problem by replicating the unique comparison of acoustic inputs in the brainstem), acoustic effects of the outer ear through proces- the human brain relies heavily on the acoustic sing of the input signal. Due to the reflections characteristics of the outer ear for localization of and resonant characteristics of the human outer sound, especially for elevation, and front/back ear, frequencies above 1.5 kHz are amplified localization. As a result, BTE users often have more for sounds from the front relative to other more trouble correctly localizing sound sources directions. As a result, a positive directivity index since the microphone is positioned above the is obtained for these frequencies (see Figure 21). Sound Comfort TruEar 4 3 2 1 Performance 0 -1 -2 -3 -4 100 500 1,000 5,000 10,000 Frequency / Hz Human BTE omni TrueEar 43 Best Fitting Directivity index / dB Figure 21 Directivity (as calculated by the DI) of the unaided open ear compared to a standard BTE (closed earmold) with an omnidirectional microphone and a BTE employing TruEar processing. Individuality ear, rather than in the ear canal. Siemens TruEar In order to restore aided localization with BTEs, TruEar mimics the frequency-specific directivity of the human outer ear. This is accomplished by adjusting the hearing instrument’s directional microphone system to match the directivity pattern of the pinna as closely as possible. As shown in Figure 21, hearing instruments equipped with TruEar provide a very similar directivity at high frequencies to the unaided ear, meaning that the brain can easily use the spectral cues available to discriminate between signals coming from the front and from the back. This benefit of TruEar has been substantiated by research. Studies conducted at the National Acoustics Laboratory in Australia (Keidser et al. 2008) show that for all signals with components above 2 kHz, TruEar significantly reduces front/ back confusions. Note that hearing instruments with a microphone located close to the ear canal entrance (such as CICs) do not require TruEar as they can use the natural pinna effects. 44 Better Hearing TrueEar & e2e wireless 2.0 in The e2e wireless settings can be accessed cessing is enabled by default to allow the two under the Wireless Settings and Accessories instruments to synchronize in terms of digital page. Under the page, there are options to signal processing. This coupling can be dis- couple the hearing instrument to remote abled if necessary. Sound Comfort Connexx controls, including Tek. Digital signal proTruEar is available in 701 and 501 series BTE Individuality instruments and is used as the default setting when the microphone is in the omnidirectional Performance mode. 45 Best Fitting Figure 22 The Wireless Settings and Accessories page in Connexx allows the HCP to designate remote controls as well as configure e2e wireless 2.0 settings. Extending bandwidth SoundBrilliance SoundBrillianceTM, another innovative algorithm Because SoundBrilliance does not operate on from Siemens, is designed to exceed the limita- high-frequency components above 8 kHz from tions of conventional hearing instrument band- the microphone signal, but generates them widths to offer users a listening experience more from lower frequencies, these additional high- similar to that of normal-hearing individuals. frequency sounds are available without any SoundBrilliance analyzes input signals and adds feedback risk. With SoundBrilliance, the output artificial high frequencies to the output up to in high frequencies can be increased up to 12 kHz. The perceived effect is a more “brilliant” 90 dB SPL in this frequency region. In terms of sound quality. SoundBrilliance is especially ben- hearing loss, this means that hearing losses eficial when listening to music, and also when up to 85-90 dB at 8 kHz can benefit from the using audio streaming via Bluetooth. This is be- SoundBrilliance feature. cause the bandwidth of Bluetooth transmission is limited to 7.5 kHz, but SoundBrilliance adds frequencies up to 12 kHz (Figure 23). 46 Better Hearing Sound Comfort 110 max med 100 min off Individuality 80 70 60 50 40 100 200 400 1k 2k 4k 8k Performance Output level / dB SPL 90 16k Frequency / Hz 47 Best Fitting Figure 23 SoundBrilliance adds ultrahigh-frequency information to a hearing instrument. SoundBrilliance – Settings in Connexx Figure 24 Fine-tuning options for SoundBrilliance 48 Better Hearing Sound Comfort How to demonstrate Set up two Bluetooth phone programs to demonstrate SoundBrilliance, one with SoundBrilliance on and one with it off. Have the customer use the Bluetooth phone while switching between the two programs to experience the difference. A user can << Individuality similar procedure using the music program. Performance also hear the difference in music with a 49 Best Fitting >> SoundBrilliance – Individu SoundLearning 2.0 Suppress unwanted noise Situation Detection DataLogging 50 Better Hearing Sound Comfort ality Often times, Better Hearing (audibility) compromises sound comfort and vice versa. For example, increasing high-frequency gain may improve Individuality speech understanding, but the user then complains that the sound quality is too shrill. The challenge, then, is to find the right balance between Better Hearing and sound comfort individually for every customer. This is further complicated by the fact that the best gain and output (prescriptive fitting) is only appropriate for the “average” Performance customer, and it too needs to be individualized. A learning hearing instrument that the user can train to arrive at the preferred settings, therefore, is the ideal solution. Individual preferences, however, also vary across listening situations. A trainable hearing instrument, therefore, should learn gain, frequency response, and compression separately for 51 Best Fitting different listening situations. Situation-specific learning with SoundLearning 2.0 The rationale behind situation-specific learning In SoundLearning 2.0, every time the user is that depending on the acoustical environ- changes the volume or SoundBalance, this ments, users have dedicated priorities with adjustment is recorded along with the current regard to sound preference. In situations where input level and detected acoustic environment. speech is present, whether it is speech in quiet This leads to a dedicated frequency response as or speech in noise, the obvious priority is speech well as compression setting for Speech, Noise, intelligibility. In noisy environments, the noise and Music. These learned new settings are then should be heard, but only at a comfortable level. selected when the system detects these situa- For music, the sound quality is most likely the tions again (Figure 25). The result is separate priority. It follows then, that depending whether settings for each of these listening situations the current listening situation is speech, noise, tailored to individual preferences. To achieve or music, the user would prefer different gain the same effect as with SoundLearning, three settings. separate learning programs would be needed, one for each acoustic situation. Additionally, the user would have to change the program manually each time the acoustic situation changes. With SoundLearning 2.0, this all occurs automatically and intuitively. 52 Speech Music Noise A B C Setting for Music Speech Automatic switching Music Setting for Noise Noise Individuality Setting for Speech Sound Comfort VC & Treble changes Universal program In mixed situations, i.e. “Music” and “Speech”, the activated setting is a mixture of the “Music” Performance and “Speech” setting. That is, SoundLearning 2.0 is able to apply a continuum of settings rather than three single settings. 53 Best Fitting Figure 25 Situation-specific learning and automatic switching Better Hearing Learning Clinical study: Event- vs. time-based learning (NAL) In any learning hearing instrument, learning can Based on the data from this study, it is possible occur in two ways. In time-based learning, the to estimate the percentage of situations with hearing instrument records a data point after comfortable loudness. While former learning al- a specific interval, say every 1 or 5 minutes. In gorithms like DataLearning and SoundLearning event-based learning, a data point is recorded were already quite successful in increasing the every time a specific event occurs, such as when percentage of situations with comfortable the user adjusts the volume control. Results of loudness (Mueller et al. 2008), SoundLearning a recent study conducted at NAL indicate that clearly outperforms and has the potential to event-based learning is more effective than achieve optimum loudness in almost all listen- time-based learning the more situation-specific ing situations (Figure 26). learning is (Keidser et al. 2009). Since Sound Learning 2.0 learns specific preferences both for different levels and situations, event-based learning is employed here. 54 Better Hearing Figure 26 Percentage of situations with comfortable loudness for various learning algorithms Sound Comfort 100 80 Individuality 70 60 50 40 DataLearning Classifier Control SoundLearning SoundLearning 2.0 Performance NAL-NL1 55 Best Fitting Situations loudness ok / % 90 Situation Detection In order to learn gain and compression settings binaural Situation Detection which allowed for reliably for different listening situations, reliable synchronous steering of both hearing instru- Situation Detection is essential. Siemens intro- ments in a binaural fitting. Today, the accuracy duced the first Situation Detector in 2002. The of Siemens situation detection is still the indus- detected acoustic situation determined the ap- try benchmark. A recent study showed that propriate directional microphones and noise re- Siemens excelled over the best competitor for duction settings so the hearing instrument was the accurate detection of all sound categories always automatically adjusted to the optimal (speech in quiet, speech in noise, noise, and setting for each acoustic situation. In 2004, this music). This was most notable for the identifi- technology was refined to become the first cation of music (correct identification exceeded best competitor by 44%) and for noise (correct 100 identification exceeded best competitor by 80 27%). See Figure 27. Detection accuracy / % Figure 27 Compared with the best competitor, Siemens situation detection is more accurate in all sound categories, especially for the sound categories Noise and Music. 60 40 20 0 Speech in quiet Speech in noise Noise Acoustic situation 56 Music BestSound Best competitor Better Hearing Figure 28 Steering of SoundLearning 2.0, automatic microphone system and Speech and Noise Management system by BestSound Technology‘s situation detector Stationary noise Fluctuating noise Omni Directional Directional / Omni Off On On / Off Speech and Noise Management SoundLearning 2.0 Speech in noise Music Speech Noise (Sound quality) (Intelligibility) (Comfort) Figure 28 illustrates how the situation detec- The directional microphone and the noise reduc- tor steers the automatic microphone system, tion system would be deactivated. In contrast, a the Speech and Noise Management system change from “Speech in noise” to “Stationary and SoundLearning 2.0. Note that depending noise” would not change the directional micro- on algorithm, the five classes provided by the phone and the noise reduction system (if “Speech situation detector have different effects. For in noise only” is unchecked), but the compression SoundLearning 2.0, a change from “Speech” to and gain setting for SoundLearning 2.0. Individuality Automatic microphone Speech Performance Music Sound Comfort Situation Detection “Speech in noise” would not result in a different frequency response or compression setting, as ty” and thus, the same setting should be used. 57 Best Fitting in both classes the listening goal is “Intelligibili- Managing SoundLearning 2.0 in Connexx SoundLearning 2.0 is accessible under the Click on the Gain Preferences tab to see learned Learning/Logging dialog (Figures 29/30). gain settings for each of the three situations Currently, SoundLearning 2.0 is only available or classes under the Universal program. When in the Universal program. Programs 2 and 3 learning has occurred for one of the three situa- support SoundLearning. When “activate tions, an exclamation point (!) will be displayed SoundLearning 2.0” is checked, the Universal in the respective situation on the pie chart. program automatically learns independent Learned values can be displayed as gain curves setting preferences for Speech, Noise, and or as channel gain (Figure 30). The HCP has the Music. After the user has worn the instruments option to apply learned settings automatically. for a certain time, the SoundLearning 2.0 dialog If learned settings are not automatically applied, shows logged information such as wearing time, the HCP has the option to apply the learned gain microphone, and Speech and Noise Management to all classes, or to reset one or all three classes usage for each selected program. More interest- back to the original settings prior to the learning ingly, the acoustical environment section shows period. Optimal learned settings for all three the percentage of times the user has been hear- classes should be obtained after approximately ing speech, noise, and music. This percentage two weeks. is also reflected in the Usage Analysis pie chart (Figure 29). 58 Better Hearing Sound Comfort 59 Best Fitting Performance Individuality Figure 29 SoundLearning 2.0 screen under the Learning/Logging dialog Figure 30 Gain Preferences tab in the SoundLearning 2.0 dialog. The HCP can view the learned settings, compare them with the initial settings and choose to reset them. 60 Better Hearing concept that can be easily demonstrated in the tected acoustic situation according to presets short amount of time allotted for most hearing after First Fit. Explain to the user that depend- instrument counseling and fitting sessions. It ing on the sounds being played, the Universal is possible, however, to demonstrate to cus- program adjusts its settings accordingly so that tomers the benefit of having three separate the speech is intelligible, the music is pleasant, settings for different acoustic situations. Use and the noise is not uncomfortable. These ad- the Audibility page of the Real Time Display to justments are also reflected in the gain chan- demonstrate the advantage of SoundLearning nels on the Audibility page. 2.0. Have the customer wear the instrument Once the user understands the advantages of and show the Audibility page for the Universal having different settings for different acoustic program with SoundLearning 2.0 activated. situations, explain that the settings currently First, switch the adaptive parameters off to in the instrument are presets or starting demonstrate the case when SoundLearning 2.0 points. When the customer uses the hearing is deactivated. Play the sound files for speech, instruments on a daily basis, the hearing in- music, and noise. Explain that there is only struments will automatically adapt these pre- one gain setting for all situations. Therefore, sets to match his or her individual preferences regardless of the sounds played, the hearing for these different listening situations. instrument responds the same way. Conse- << quently, the speech and noise may sound suboptimal. Now, switch to “Current” to activate SoundLearning 2.0. Play the same sound files Individuality again. Now, gain settings change with the de- Performance Since learning occurs over time, it is not a Sound Comfort How to demonstrate 61 Best Fitting >> SoundLearning 2.0 – Performa levels To ensure that as many users as possible benefit from the BestSound Technology, it will be available in all performance levels. Figure 31 shows the distribution of BestSound Technology in four different performance levels. Figure 31 The distribution of BestSound Technology in four different performance levels 62 Audibility Better Hearing Sound Comfort nce AGCi AGCo Directional microphone Automatic Auto/Adaptive Auto/4-ch. adap. SpeechFocus – – – Soft Level Directivity – Yes Yes Yes e2e wireless – Yes Yes Yes Eliminate feedback FeedbackStopper Yes Yes Yes Yes Suppress unwanted noise SoundSmoothing – Yes (on/off) Yes (off + 3 steps) Yes (off + 3 steps) S. and N. Management Yes (off + 3 steps) Yes (off + 3 steps) Yes (off + 5 steps) Yes (off + 7 steps) eWindScreen Yes (on/off) Yes (on/off) Yes (on/off) Yes (on/off) TrueEar – – Yes Yes e2e wireless – Yes Yes Yes SoundBrilliance – – Yes Yes Learning – DL SL SL Sound Comfort Optimize localization Extend bandwidth Individuality Learning and Logging Individuality Performance Speech intelligibility Auto/4-ch. adap. Situation Detection Logging 63 Best Fitting Better Hearing Explaining performance levels to users 64 Although it is relatively easy to describe differ- problems and in which situations they need the ent performance levels by feature distributions, most support. The needs of individuals with it may be difficult to describe these differences hearing loss can be categorized into five common in a way that can be easily understood by users. listening situations: speech in quiet, speech in Users may not understand the technology be- noise, watching TV, on the phone, and listening hind the features and their benefits. They do, to music. For each of these situations, Siemens however, know in which situations they have has dedicated a statement and an illustration. No. Situation Statement 1 Speech understanding in quiet I want to hear others well. 2 Speech understanding in noise I want to hear others well in background noise. 3 Listening to TV I want to hear my TV. 4 Using the phone I want to hear well when using my phone. 5 Listening to music I want to hear my favorite music. Better Hearing Sound Comfort To help Hearing Care Professionals explain performance level differentiation, Siemens has developed a rating system which shows how effectively each of the performance levels addresses these five situations (Figure 32). This rating is based on the available features Individuality in the respective performance levels. Figure 32 Overview of BestSound Technology performance levels I want to hear I want to enjoy “my “others better when favorite TV ” there’s background shows. ” noise. ” I want to hear “well when using my phone. ” I want to hear my “favorite music. ” Performance I want to hear “others properly. 501 301 101 The lengths of the bars show you which performance level suits your needs best. with Tek 65 Best Fitting Performance level 701 The following table lists the BestSound Technology features which improve the listening experience in each of these five situations. No. Statement Situation Features that improve the situation 1 I want to hear others Speech understan- • Amplification, compression, output limiting well. ding in quiet • Situation Detection • Learning and logging 2 I want to hear others Speech understan- • Amplification, compression, output limiting well in background ding in noise • Directional microphone noise. • SpeechFocus • Speech and Noise Management • SoundSmoothing • eWindScreen • Situation Detection • Learning and logging 3 I want to hear my TV. Listening to TV • Amplification, compression, output limiting • SoundBrilliance • Tek and Tek Transmitter • Learning and logging 4 I want to hear well Using the phone • Amplification, compression, output limiting when using my • AutoPhone phone. • Synchronization with e2e wireless • Tek (binaural phone) • Learning and logging 5 I want to hear my fa- Listening to • Amplification, compression, output limiting vorite music. music • SoundBrilliance • Situation Detection • SoundLearning 2.0 66 Sound Technology, it is considered so essential level is better in each of the five listening that it is offered in all performance levels. As a situations and offers some suggestions when result, FeedbackStopper is not used to differen- counseling customers to consider a higher tiate performance levels. The following sub- performance level. Better Hearing chapters explain why a higher performance Sound Comfort While FeedbackStopper is a key feature in Best For many users, this is the listening situation Consider the following arguments when coun- where they have the least amount of problems. seling customers: Individuality Speech understanding in quiet As a result, their needs for speech understandavailable in the 101 instruments. To explain why loss, at a minimum you need the attributes a higher-level instrument would be helpful in of the X01 level technology in order to map this situation, focus on the higher number of speech and environmental sounds into your channels available. dynamic range. Performance • Based on the configuration of your hearing • The higher performance levels offer dedicated learning features which help to find your preferred individual setting. This is especially important if the user does not have a way to control the gain (VC or remote). If they do not have an “average” loudness growth function, they will need to readjust the relationship between soft and loud speech. 67 Best Fitting ing in quiet can often be met by technology Speech understanding in noise Speech understanding in noisy situations is per- When choosing hearing instruments for users haps the most common problem reported by who are often not able to understand speech in those with hearing loss. Siemens hearing instru- noisy situations, point out the following facts: ments employ directional microphone systems and different noise reduction algorithms to im- • To be able to understand speech in noise, an prove speech intelligibility and listening comfort effective directional microphone system and in noisy situations. noise reduction algorithms are essential. • Higher performance levels offer more sophisticated directional microphones and noise reduction features. In the premier performance level 701, for example, the SpeechFocus option ensures the best possible speech intelligibility, even in situations where speech comes from the side or from behind. • Siemens hearing instruments use up to four different algorithms to reduce the annoyance of noise. Not only do higher performance levels offer more noise reduction algorithms, they also allow more flexibility and precision to meet your individual requirements. 68 Better Hearing Listening to TVs To watch TV without disturbing others can also For users who enjoy watching TV, make sure be challenging for hearing instrument users. To they understand the following: struments together with the Tek system should Sound Comfort solve this problem, at the minimum 301 level in• For optimal viewing pleasure without be recommended. Furthermore, SoundBrilliance disturbing others, the 301 performance available in 501 and 701 instruments further level together with the Tek system should improves the enjoyment of TV by offering an be considered. extended frequency range which results in a Individuality the 501 performance level, which offers a more brilliant sound, especially for the wirelessly transmitted stereo sound from the TV. • The higher performance levels are more flexible when learning your preferred Performance ing via Bluetooth. • If sound quality is very important, consider sound settings. 69 Best Fitting ”bright“ sound quality, especially when stream- Using the phone Using the telephone can sometimes be espe- This solution significantly improves the speech cially difficult for those with hearing loss. Many intelligibility for phone calls because the phone products in all performance levels offer the signal is transmitted to both hearing instru- AutoPhone feature. These products are able to ments in a binaural fitting. For landline phones detect a telephone as soon as it comes close to without Bluetooth functionality, Siemens offers the hearing instrument. Based on this input, the a landline phone adapter which can easily be hearing instrument automatically switches to a connected to make the phone Tek-compatible. dedicated phone program. In 301 instruments, A 301 or higher-level instrument, as well as the the programs of both instruments in a binaural Tek are necessary to take advantage of this fitting are synchronized so that while one hear- solution. ing instrument is in the phone program, the other instrument can be in a quiet program to minimize distracting environmental sounds. An even more sophisticated solution is the use of a Bluetooth-enabled phone with Tek. 70 Better Hearing Consider the following when counseling cus- Sound Comfort tomers about using the telephone: • The ideal solution for phone calls is clearly the use of Tek with 301 hearing instruments or higher. If your phone does not support Bluetooth, Siemens offers a landline phone adapter that connects your phone via Bluetooth to the Tek system. When you have two Individuality hearing instruments, Tek allows you to listen to the phone conversation in both ears, a proven advantage that even normal-hearing people do not have. • If you prefer not to use Tek, consider at least a feature is available in a 101 product, a 301 product can promote listening ease by synchronizing programs in a binaural fitting. 71 Best Fitting Performance model with the AutoPhone feature. While this Listening to music Listening to music with hearing instruments is When counseling music lovers about perfor- not always the most enjoyable experience be- mance level differentiations, bear these points cause most hearing instruments features are in mind: dedicated to improve speech intelligibility, which may not result in the optimal sound quality for • To offer a good sound quality, it is important music. It is important, therefore, that a hearing for the hearing instrument to differentiate instrument is able to differentiate music from music from other acoustic situations. Siemens speech. The good news is that with Siemens, situation detector is the industry benchmark all performance levels employ state-of-the-art in terms of accurate detection of acoustic situ- situation detection that can reliably differentiate ations, including music. The situation detector music from speech. is available in all performance levels. The 701 instruments, however, can do even • Everybody has individual preferences in regard more. These products learn individual sound to how music should sound – some prefer preference for the situations speech, music, more bass, some prefer more treble. Hearing and noise so that the preferred sound setting instruments in the 701 performance level in- is automatically used every time one of these tuitively learn the user´s listening preferences situations is detected. Furthermore, 701 and for music as well as for speech and noise, and 501 instruments offer SoundBrilliance, which automatically switch to the preferred settings further improves the sound quality of music. as soon as one of these situations is detected. Furthermore, SoundBrilliance available in 701 and 501 instruments offers an extended bandwidth, which means that music sounds even brighter and more vivid. 72 Best Fitting 73 Performance Individuality Sound Comfort Better Hearing Best 74 Better Hearing Sound Comfort Fitting BestSound Technology improves speech intelligibility and hearing comfort while accounting for individual needs and unique listening Individuality situations. Despite the sophistication of BestSound Technology, Siemens wants to ensure that fitting these hearing instruments is easier and more intuitive than ever. Therefore, Siemens also offers the Best Fitting Support with our wireless programming interface ConnexxLink, NAL-NL2 as a fitting formula, and a host of other 75 Best Fitting Performance features to facilitate every step of the fitting process. ConnexxLink: Wireless programming interface ConnexxLink, Siemens´ completely wireless ConnexxLink is compatible with all hearing programming interface, is launched together instruments featuring the new BestSound with the BestSound Technology portfolio. Simply Technology on 701, 501, and 301 performance plug in the prepared dongle into the USB port levels, as well as all custom instruments with of your PC, and have your customer wear e2e wireless 2.0. ConnexxLink around the neck. ConnexxLink employs Bluetooth technology for the PC to communicate instantaneously and wirelessly with the hearing instruments so that Hi-Pros and programming cables and adapters are no longer needed. Not only will ConnexxLink facilitate ease of programming for Hearing Care Professionals, it will also provide customers a greater degree of freedom and comfort during the fitting process. Figure 33 compares the programming time of three commercially available wireless programmers for typical tasks during a fitting session. Except for two of the selected situations, ConnexxLink is the fastest system available. 76 Better Hearing 100 Sound Comfort 60 40 Individuality 20 0 Apply first fit First readout CGM measurement Store data in HI ConnexxLink competitor 1 competitor 2 Performance Detect instruments 77 Best Fitting Figure 33 Programming time of three wireless programming interfaces for various fitting tasks Programming time / s 80 Prescriptive fitting: NAL-NL2 & ConnexxFit Siemens Connexx 6.4 is the first fitting platform Achieving the optimal hearing instrument set- that supports the NAL-NL2 fitting formula. Like ting for each individual customer is a multistep its renowned predecessor NAL-NL1, NAL-NL2 is process. First of all, a proven fitting formula an extensively researched and proven formula which takes as many individual factors into developed by the National Acoustic Laboratory account as possible should be the basis of any in Australia. Unlike NAL-NL1, however, this version gain and output prescription. For this step, of the prescriptive formula takes more individual NAL-NL2 is the ideal base formula. In the next factors into account, including age, gender, hear- step, ConnexxFit takes specific Siemens hearing ing instrument experience, and language. instruments and individual ear acoustics into account to result in a First Fit that offers appro- In addition to NAL-NL2 as a separate fitting option, priate amplification and supports spontaneous ConnexxFit, Siemens´ proprietary fitting formula, acceptance at the same time. After the custo- is now also based on NAL-NL2. ConnexxFit makes mer has worn the instruments for a few weeks, modifications to NAL-NL2 based on instrument- the fine-tuning adjustments made by Hearing specific properties and individual ear acoustics Care Professionals as well as SoundLearning to optimize spontaneous acceptance. Various 2.0 finally arrive at an individual fit that is most studies have shown that ConnexxFit is preferred appropriate for the customer. Due to the sen- by most users without degradation of speech sory deprivation caused by hearing loss, which intelligibility. usually occurs over the course of decades, new hearing instrument wearers often only accept gain that is not quite optimized for audibility and speech intelligibility, even after a few weeks of amplification. What is needed for customers 78 NANL2 Gender Language Age Target gain ConnexxFit Individual critical gain curve First Fit Sound Learning Fine-Tuning Better Hearing Sound Comfort NANL1 Dispenser / Audiologist supported by learning and logging feature Individual fit Individual sound parameters Hearing instrument parameters Experience to acclimatize to amplification and to “re-train” the brain to make the most of the sounds now Performance being heard again, therefore, is active auditory training (Taylor 2008 & Shrive, Hawkins 2005). For this final step in the fitting process, Siemens offers eARena, a computer-based auditory training program. This process is illustrated in Figure 34. 79 Best Fitting Figure 34 Illustration of how Siemens fitting and support tools help to arrive at an individual fit that is tailored to each customer Siemens Individuality National Acoustic Laboratory Australia, Harvey Dillon AutoFit: Match to target with a click of a button While most Hearing Care Professionals adjust match the targets prescribed by these formulas. hearing instrument gain and output settings to This can often be a tedious and time-consuming individual user preferences, many still prefer, or process where multiple measurements have to are required to prescribe gain settings accord- be made as the gain for low, mid, and high in- ing to traditional fitting formulas such as DSL, puts is slowly adjusted to approach targets. NAL-NL1, or NAL-NL2. In the latter case, the HCP Figure 35 The AutoFit dialog in Connexx 80 typically performs real-ear measurements and Siemens AutoFit is an option within the Connexx adjusts the hearing instrument gain until they in-situ feature which automatically adjusts the efficiency of AutoFit in real clinical situations. lizing the measurement systems Siemens Unity For 10 test ears and 5 audiograms of various 1, Unity 2, or Aurical to carry out real-ear mea- configurations, the study compared the time, as surements. This data is then used by Connexx well as the number of mouse-clicks it took for to automatically adjust the hearing instrument an experienced HCP familiar with Connexx to frequency response to match specified prescrip- perform in-situ fittings via manual adjustments tive targets in the ear. This allows the HCP to and via AutoFit. Results show that AutoFit sig- perform in-situ measurements without initial- nificantly reduces the time and the number of izing the measurement software separately, and mouse-clicks without sacrificing the accuracy of thereby significantly reduces time for fitting the match to prescriptive targets (Figure 36). 140 30 120 25 100 Time (seconds) 35 20 15 80 60 10 40 5 20 0 Manual adjustments AutoFit Number of mouse-clicks required for in-situ fittings Manual adjustments AutoFit Time required for in-situ fittings 81 Best Fitting 0 Better Hearing button (Figure 35). AutoFit works by directly uti- Sound Comfort internal study was carried out to evaluate the Individuality match prescriptive gain targets at the click of a Performance hearing instruments to prescriptive targets. An Mouse-clicks Figure 36 Number of mouse-clicks and time required for an experienced HCP to complete in-situ fittings via manual adjustments and via AutoFit frequency response of a hearing instrument to Counseling & Training Real Time Display Real Time Display is a counseling tool within the relative to the range of audibility so that it can Connexx fitting software. This feature enables be used to help customers and family members HCPs to demonstrate visually and acoustically understand what the hearing instrument does key hearing instrument features. The Real Time in terms of amplifying speech, and why ampli- Display is separated into four tabs featuring fication is necessary given the patient’s hearing Audibility, Noise Reduction, SpeechFocus, and loss. The Noise Reduction page shows the ability Adaptive Directional Microphone. The Audibility of the instrument to reduce gain for noise in page shows the instantaneous input and output 16 channels. The effects of the various noise of the 16 gain channels as well as the detected reduction features in the hearing instrument, acoustic situation. This information is shown including SoundSmoothing, can be demonstrated. The SpeechFocus page shows how 701 hearing instruments can detect speech from all around the user and activate the appropriate microphone mode accordingly. The Adaptive Directional Microphone page shows the ability of the adaptive directional microphone to suppress moving noise sources that come from the rear hemisphere. 82 Better Hearing poignantly, sound files that are provided allow within the Connexx fitting software designed others to hear “with” the patient’s hearing loss. to help families and significant others to under- When family and significant others truly under- stand the impact of the patient’s hearing loss stand the detrimental effects of hearing loss, (Figure 37). By plotting the patient’s hearing they can become more involved and supportive loss on the audiogram, the hearing care pro- in obtaining hearing instruments for the cus- vider can explain how the hearing loss affects tomer. speech and environmental sounds. Even more Performance Individuality Figure 37 The Hearing Loss Simulator allows friends and family members to experience hearing loss. 83 Best Fitting The Hearing Loss Simulator is a counseling tool Sound Comfort Hearing Loss Simulator eARena For most users, hearing instruments are very Siemens eARena™ is a computer-based auditory effective in restoring audibility. Even the most training program specifically designed to help advanced technology, however, is not able to users make the most of their hearing instru- restore listening, comprehension, cognitive, and ments (Figure 38). It is a 20-day program with communication skills. Since hearing loss usually 30-minute auditory exercise programs each day. occurs gradually over a long period of time, The exercises are designed to improve auditory sensory deprivation often causes the brain to skills such as perception of everyday sounds, “forget” what it is like to hear all the sounds in word recognition, timbre discrimination and the environment. This is why after initial amplifi- speech understanding in noise. In addition to cation, the brain is not always able to efficiently being highly rewarding for the customer, eARena make use of the restored audibility. is also advantageous to the HCP because it results in higher satisfaction with new hearing instruments and fosters customer loyalty. 84 Better Hearing 85 Best Fitting Performance Individuality Sound Comfort Figure 38 Siemens eARena auditory training program helps customers to acclimatize to new hearing instruments. A final word For over 130 years, our goal has been to redefine SoundLearning 2.0 is the first trainable hear- the future of hearing care. Our story began in ing instrument to learn optimum frequency 1878, when Werner von Siemens invented the response and compression setting in different Phonophor, the first special telephone receiver environments. for people with hearing loss. Now with Best Sound Technology, we’ve come even closer to In combination with a variety of additional our goal of ensuring that every person enjoys proven signal processing techniques and new every decibel of life to the fullest. With a suite of fitting features like ConnexxLink, NAL-N2 and sophisticated innovations such as Feedback AutoFit, BestSound Technology allows Hearing Stopper, SpeechFocus and SoundLearning 2.0, Care Professionals to effectively and easily fulfill BestSound Technology sets a whole new the individual needs of their clients. standard in hearing care. These three key innovations directly address the major needs of hearing instrument wearers – Better Hearing, Sound Comfort and individuality: SpeechFocus is the first directional microphone to automatically select backward directivity. FeedbackStopper is the industry benchmark feedback canceler with transient frequency shifting. 86 Abbreviations • AGCi Automatic Gain Control input-related • PA Phone Adapter • AGCo Automatic Gain Control output-related • SNR Signal-to-noise ratio • HCP Hearing Care Professional refers to both • UCL Uncomfortable level audiologists and dispensers References Branda, E. & Herbig, R. (2010). Frequency shifting for improved feedback suppression. Submitted. Kochkin, S. (2005). Customer satisfaction with hearing instruments in the digital age. The Hearing Journal, 58(9), 30-43. Branda, E. & Hernandez, A. (2010). New directional solutions for special listening situations. Submitted. Mueller, H., Hornsby, B., & Weber, J. (2008). Using trainable hearing aids to examine real-world preferred gain. Journal of the American Academy of Audiology, (19)10, 758-73. Hawkins, D. (2005). Effectiveness of counseling-based adult group rehabilitation programs: A systematic review of the evidence. Journal of the American Academy of Audiology, 16, 485-493. Ricketts, T. & Picou, E. (2008). Strategies for telephone listening for people with hearing loss. Poster presentation at AAS 2009, Scottsdale, U.S. Hernandez, A., Chalupper, J. & Powers, T. (2006). An assessment of everyday noises and their annoyance. The Hearing Review, 13(7), 16-20. Powers, T. A., Burton, P. (2005). Wireless technology designed to provide true binaural amplification. Hearing Journal, 58 (1), 25–34. Keidser, G., O‘Brian, A., McLelland, M. & Yeend, I. (2008). The effect of frequency-specific directionality on horizontal localisation. Submitted. Smith, P., Davis, A., Day, J., Unwin, S. Day, G. & Chalupper, J. (2008). Real-world preferences for linked bilateral processing. The Hearing Journal, 61(7), 33-38. Keidser, G., Rohrseitz, K., Dillon, H., Hamacher, V., Carter, L., Rass, U. & Convery, E. (2006). The effect of frequency-specific directionality on horizontal localisation. International Journal of Audiology, 45(10), 563-579. Taylor, B. & Shrive, A. (2008). The economics of computerbased auditory training. Online article: AudiologyOnline.com. Keidser, G., Convery, E. & McLelland, M. (2009). A trainable hearing aid: effectiveness of training method and the influence of auditory training. Unpublished NAL Study Report, 2009. 87 The information in this document contains general descriptions of the technical options available, which do not always have to be present in individual cases and are subject to change without prior notice. The required features should therefore be specified in each individual case at the time of conclusion of the respective contract. Global Siemens Headquarters Siemens AG Wittelsbacherplatz 2 80333 Muenchen Germany Global Business Unit Siemens Audiologische Technik GmbH Gebbertstrasse 125 91058 Erlangen Germany Phone: +49 9131 308 0 Global Siemens Healthcare Headquarters Siemens AG Healthcare Sector Henkestrasse 127 91052 Erlangen Germany Phone: +49 9131 84 0 www.siemens.com/healthcare www.siemens.com/hearing Order No. A91SAT-01041-99C1-7600 | Printed in Germany | © 04.2010 Siemens AG Legal Manufacturer Siemens Audiologische Technik GmbH Gebbertstrasse 125 DE-91058 Erlangen Germany