Bluetooth and Hearing Aids: Ready for prime time? - Part One

by Mark Ross, Ph.D.

Editor: Mark Ross always has interesting analyses of various topics related to hearing loss, and the current offering is no exception. Here he reviews the currently-available devices that allow hearing aids to communicate with Bluetooth enabled devices, and then addresses the issue of the readiness of these systems for prime time.

This article originally appeared in "Hearing Loss" magazine, and is republished with the kind permission of the author.

This is part one of two parts.

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January 2009

When I was growing up in New York City, it was not uncommon to see someone having an animated conversation, apparently with himself since no conversational partner could be observed. It was rather a strange sight, but since the people doing this were generally harmless (except perhaps to themselves) they were basically ignored as they walked and talked. In my recent visits to NY, I see the same apparent phenomenon - only multiplied a thousand fold. On just about any street in midtown Manhattan, there are people walking and talking, apparently to themselves, seemingly oblivious to their surroundings. Upon close examination, however, they all have one thing in common: a bluetooth receiver sticking out of their ears. It is clear that they are talking to a real human being, using a cell phone with a hands-free arrangement; no one categorizes them as having some sort of psychological problem (at least on this basis!). People with hearing loss want to know if they too can use a cell phone, in the same cool and convenient manner, with a bluetooth connection. The answer is that they can, but not in the exact same way. Although hands-free connection can be made, it is not quite as easy to do as it is for someone with normal hearing, at least not presently.

Bluetooth came by that strange name just about ten years ago when a consortium of electronic companies, mainly from Scandinavia, joined together to agree on a common wireless protocol. The term refers to an ancient Nordic king who united many tribes in a single kingdom. Essentially, this is what the bluetooth operation does; it wirelessly connects (unites) all sorts of electronic devices. It does this by transmitting a detailed set of operating instructions from one electronic component to another. The information is coded so that the transmitted signal is received only by an intended receiver. Early examples of bluetooth operation were between various computer components, later extended to cell phones and a host of other devices. Among its advantages is its low power and limited transmission range; this helps ensure an interference-free signal that can be received only by the intended recipient of the message. For hearing aid users, the major potential advantage of bluetooth at this time lies in the distortion-free access it can provide to cell phone communications. While there are other electronic sound signal outputs that can be accessed via a bluetooth receiver (e.g., an mp3 player, TV, computer, etc.), right now the potential application with cell phones seems the most pertinent.

In spite of the many advances in wireless communication and hearing aids (in part because of the advocacy efforts by the HLAA), the quality of the verbal signals heard through hearing aids may still be contaminated by various sorts of interference (ambient electromagnetic noise, sound fluctuations caused by hearing aid positional changes, etc.). Then, too, hands-free conversation, which would be a major convenience for some hearing aid users (besides just looking "cool"), is not possible with the conventional use of a cell phone. Hence, the interest in bluetooth technology by hearing aid companies; they have identified a need and it is in their business interest to fill that need. A few manufacturers have responded to this challenge, each in their own way.

More on this and related topics

Several years ago, the Starkey Company marketed the ELI, a "miniature" (about one inch long) bluetooth receiver that could be plugged into the base of a behind-the-ear hearing aid. With it, one could directly connect to a remote cell phone (in a purse or on one's belt, for example) and carry on a distortion-free telephone conversation. It was (and is) the only device that permitted a direct electrical connection to a hearing aid from a bluetooth receiver; I tried it myself and I thought it worked well. However I have recently learned that the ELI (along with two companion products, a remote bluetooth transmitter and a neckloop) is no longer being made and marketed; evidently, ELI was not yet ready for "prime time." As well as it worked, it was not adopted by enough people to make it an economically viable product. People who now possess the ELI or the ELI neckloop (into which the ELI module is plugged) can still realize a hands-free arrangement while using their cell phones, but the current generation of this product line is being phased out.

The Phonak Company has two entries in the bluetooth market. The first is the Smart-Link FM microphone/transmitter, which has included bluetooth capability from the time of its introduction some four years ago. Pairing and connecting the transmitter to a compatible cell phone (one that also include bluetooth capability) is a straightforward process (or so I'm told!). When a cell phone is paired to the Smart-Link, incoming calls will first be transmitted (via a bluetooth signal) to the Smart-Link which then re-transmits the incoming call (via an FM radio signal) to hearing aid(s) that incorporate FM capability. There is a possibility that this double transformation - from the phone to the Smart-Link and thence to the hearing aids - may affect the quality of the telephone message, but we don't really know; generally, the fewer transformations a signal has to undergo, the better. Because of the limited range of a bluetooth transmission, in order for a phone call to connect to the Smart-Link the two devices must be in close proximity. Therefore, the most likely candidate for this use of bluetooth is someone who is a habitual user of both an FM system and a cell phone; for example, a person who routinely keeps the FM microphone dangling on a strap around his or her neck. So, with this procedure, while a "hands-free" connection to a cell phone can indeed be made, it can be done only by relaying the phone call via an FM transmission to the hearing aid.