Topics in Amplification CONNECTIVITY COMMUNICATION WITHOUT LIMITS

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1 January 2018 Topics in Amplification CONNECTIVITY COMMUNICATION WITHOUT LIMITS Speech understanding is best in quiet situations when listening to one speaker. While listeners do encounter this situation, they also encounter a variety of other situations that range in their level of complexity. In regard to listening situations, complexity can include but is not limited to the amount of background noise, the number of speakers, the amount of reverberation in the room, and the distance from the speaker. Technological features in hearing aids have been created specifically to reduce the struggle for good speech understanding caused by these environmental obstacles. Compression, used to improve speech intelligibility and maintain listening comfort with hearing aids, can actually have harmful effects on the output signal-to-noise ratio (SNR) in reverberant environments and when there is background noise with various speakers (Reinhart et al., 2017). The study found that with more speakers the noise is less modulated which causes the signal processing to amplify the background noise during speech pauses, consequently degrading the SNR. For this reason, there are still limits to the benefits that hearing aids can provide alone, in particular for listening situations where extra help is necessary. This extra help is often provided by assistive listening devices (ALDs). ALDs refer to devices that help improve speech intelligibility for people that have difficulty distinguishing speech in noise and/ or reverberation. In other words, they improve the signal-to-noise ratio (SNR). Improvement of the SNR is the overall goal for helping anyone understand speech in noise. MacPherson & Akeroyd (2014) showed the relationship between improved speech recognition and SNR with a review of articles testing this interaction across various test set-ups. The amount of improvement varies, but the study found that overall, an improved SNR will lead to better word recognition. To achieve a better SNR, hearing aids have been used together with ALDs for many years. As with hearing aids, the technology of the ALDs has improved. Hearing care professionals (HCPs) will be familiar with telecoil loops, FM systems, and direct audio input (DAI) used to help hearing aid users hear better in difficult and important listening situations. Because the devices don t use the microphones of the hearing aids to transmit the sound, the surrounding noise is not amplified giving the end user a clear signal with only the content that they want to hear. Further accessories were introduced to help hearing aid users connect with external devices without a cable. These accessories were intermediary devices that acted as a go-between for the hearing aids and devices such as phones and television adapters. The intermediary device was normally worn around the neck in order to transmit the signal. However, the intermediary device is no longer necessary! Near-field magnetic induction (NFMI) and Radio Frequency (RF) transmission are now used with hearing aids. NFMI is designed to contain energy within a localized magnetic field and does not radiate into free space. The energy radiates around the communication system only (Galster, 2010). Regarding hearing aids, it is used for communication between the hearing aids (ear-to-ear). For example, with Bernafon hearing aids the end user can change the volume of both hearing aids by pressing the button on one device. RF transmission uses an antenna to communicate over short wavelength radio waves in the range of 2 to GHz ( Now that the hearing aids are designed to contain this antenna, they can communicate directly with other devices that have 2.4 GHz transmission

2 Topics in Amplifi ation DUAL-RADIO WIRELESS TECHNOLOGY a) NFMI short distance ear-to-ear b) 2.4 GHz long distance direct-to-hearing aid Figure 1. Two wireless systems integrated into one hearing aid: The different uses of NFMI and 2.4 GHz are shown capability without an intermediary device. In this paper, the options for connectivity with Zerena hearing aids will be described, the use of the new SoundClip-A explained, and the fine-tuning options for accessories demonstrated. Boundless options For users of Bernafon hearing aids, the Zerena family of instruments has opened the possibility of direct wireless communication with various external devices. In order to achieve the best communication using the least amount of energy, both NFMI and 2.4 GHz transmission methods are used to fulfill all of the communication needs for Zerena. The two methods are illustrated in Figure 1. The advantage of using NFMI for ear-to-ear communication between the hearing aids is that it travels well around the head and body, has a very low power consumption, is not affected by interference from other wireless devices, and maintains excellent connectivity in the near field. However, the range is limited, and there are no external devices using it as a means of connectivity. To connect to external devices a universal system is needed that is accepted globally, such as 2.4 GHz wireless transmission. Bernafon uses 2.4 GHz wireless transmission in Zerena hearing aids to connect directly to external devices including cellular phones and other Bluetooth capable devices. The philosophy behind the use of the two transmission technologies is to avoid using more energy than needed, thus helping preserve the overall battery consumption of the hearing aids. This is particularly achieved by using the 2.4 GHz Bluetooth Low Energy (BLE) wireless transmission that provides a strong connection over longer distances and requires a lower power consumption compared to classic Bluetooth. Different 2.4 GHz wireless protocols are used depending on the type of communication required between the devices. There are four protocols: Classic Bluetooth, Standard Bluetooth Low Energy (Standard BLE), 2.4 GHz proprietary long-distance Bluetooth Low Energy (Proprietary BLE), and Apple Bluetooth Low Energy (ABLE), Made for iphone. Figure 2 shows all of the devices that will communicate wirelessly with the Zerena hearing aids with colored lines that correspond to the protocol that each device requires.

3 Topics in Amplifi ation iphone direct streaming FittingLINK 3.0 TV-A SoundClip-A EasyControl-A app Bluetooth devices RC-A Figure 2. The devices with which Zerena hearing aids connect wirelessly and the 2.4 GHz wireless protocols: Classic Bluetooth (red), Standard BLE (blue), Proprietary BLE (green), and ABLE (purple). The Proprietary BLE (green) is used for the SoundClip-A and the TV-A which transfers data and sound and allows for up to 15 m of transmission distance between the hearing aids and the devices. Standard BLE (blue) is used for transferring data only such as information between the hearing aids and the remote control RC-A, the EasyControl-A app (used as a remote control), and the FittingLINK 3.0. Information streamed between an external device and the SoundClip-A uses Classic Bluetooth (red). Direct streaming from an iphone, ipod, ipad to the hearing aids uses the ABLE (purple) protocol. Streaming directly from the phone for conversations or from the TV-A when watching television will improve the SNR as the microphones from the hearing aids will amplify less or even zero surrounding noise, depending on the selected microphone balance setting. The SoundClip-A will improve the SNR in a restaurant or meeting by giving the speaker the accessory to use as a microphone and streaming the voice directly to the hearing aids. In this situation, it works similarly to the FM systems used in schools. Users report additional benefits from hearing aids when used with accessories supported by wireless technology 1 (Smith & Davis, 2014). Hearing aid users will require different levels of training in order to operate the accessories; however, the same study reported that end users found the devices quite easy (p.73) to use. Incorporating wireless technology into normal hearing aid use will give clients more satisfaction and benefit in those tricky situations in which they may still struggle. Flexible remote mic The introduction of the new SoundClip-A extends the streaming possibilities even further. The SoundClip-A is similar to the SoundGate Mic that was available for the previous Bernafon devices except that it offers more capabilities. It works as a remote microphone but also allows for hands-free phone calls, streams phone calls directly from any Bluetooth (version 2.1 or higher) compatible phone, streams music, and functions as a remote control. Figure 3 shows how the SoundClip-A connects the hearing aids to various phones and other Bluetooth devices. For information on compatibility, please visit:

4 Topics in Amplifi ation Because the Zerena hearing aids are Made for iphone, direct streaming to the hearing aids is only possible with the iphone. However, the new SoundClip-A streams with any Bluetooth compatible phone or other device that uses a Bluetooth version 2.1 or higher. Pairing the SoundClip-A with any Bluetooth compatible phone, including an iphone, allows the user to have hands-free phone calls by using the microphone of the SoundClip-A. The SoundClip-A is worn by the enduser, and therefore, still leaves the user free of any cable or loops around their neck. The ability to accept or reject phone calls with the buttons on the SoundClip-A lets the user leave their phone in their pocket or purse. The SoundClip-A will also work on Skype phone calls over the computer when the BTD800 USB dongle is inserted into the computer facilitating Skype calls directly to the user s hearing aids. The SoundClip-A is a small device that offers big advantages for the user. Effective fine-tuning Hearing aid fittings with the Zerena family of hearing aids can now be performed wirelessly using the FittingLINK 3.0. The FittingLINK 3.0 connects the hearing aids directly to the software without the use of an intermediary neck loop or cables. A fitting without cables or neck loops will be appreciated by you and your clients. Connect wirelessly to Oasisnxt and make adjustments to the accessories to create the most beneficial use of accessories for your clients. Oasisnxt provides a dedicated screen for the fine-tuning of the accessories. Adjust the phone, SoundClip-A, and TV-A input balance so that the microphones still amplify some surrounding sounds or so that only the streamed sound is heard. The fitting screen is shown in Figure 4. Figure 3. Functionality of the SoundClip-A

5 Topics in Amplifi ation Figure 4. Screenshot from Oasis nxt of the Accessories fine-tuning screen. As seen in the screenshot from Figure 4, the different input sources can be selected from the bottom of the screen (Smartphone, TV, or SoundClip-A). Use the Sound settings to adjust the balance between the hearing aid microphones and the accessory. Additionally, the sound perception option adds more or less sharpness to the sound quality of the accessory input. The Low Frequency Enhancer adds more bass sound for those that require an extra boost of volume. Users may complain that they are adjusting their volume control whenever switching between inputs (i.e., Program 1 to phone streaming). This is the key indicator that you should make permanent fine-tuning adjustments in this screen to decrease the adjustments that the user has to make. The range of modification will help you find the right settings for each of your clients. Furthermore, the RC-A is no longer paired through the fitting software. Pair the RC-A anytime to the hearing aids simply by opening and closing the battery doors of the hearing aids and pressing a button on the remote. The wireless connectivity allows for a more comfortable and flexible fitting of the hearing aids and accessories. Unrestricted technology Your clients can start enjoying many of the benefits of wireless technology today. Clients will be excited to see that their hearing aids are keeping pace with the rest of technology. Increase their satisfaction from the hearing aids by improving the benefit that they receive in difficult listening situations. For those that already wear Zerena instruments, make sure that they are aware of all the options available to them, and invite them to try the SoundClip-A. Help new clients by showing them how to pair their phone to the hearing aids to remove any illusions of difficulty, and to allow them to experience the benefits immediately. Wireless connectivity will prove valuable to you and your clients.

6 Topics in Amplifi ation References MacPherson, A. & Akeroyd, M.A. (2014). Variations in the slope of the psychometric functions for speech intelligibility: A systematic survey. Trends in Hearing 6(18), Galster, J.A. (2010). A new method for wireless connectivity in hearing aids. The Hearing Journal, 63, Reinhart, P., Zahorik, P., & Souza, P.E. (2017). Effects of reverberation, background talker number, and compression release time on signalto-noise ratio. Journal of the Acoustic Society of America, 142(1), EL130-EL135. Smith, P. & Davis, A. (2014). The benefits of using bluetooth accessories with hearing aids. International Journal of Audiology, 53(10), Apple, the Apple logo, iphone, ipad, ipod touch, and Apple Watch are trademarks of Apple Inc., registered in the U.S. and other countries. App Store is a service mark of Apple Inc. Android, Google Play, and the Google Play logo are trademarks of Google Inc. Headquarter Switzerland Bernafon AG Morgenstrasse Bern Phone Fax Bernafon Companies Australia Canada China Denmark Finland France Germany Italy Japan Korea Netherlands New Zealand Poland South Africa Spain Sweden Switzerland Turkey UK USA /UK/subject to change