Up until March 2023 I used to post about digital audio and how things like networks could be improved for dramatically better sound quality. Earlier the same month I had finally finished a five year long project to establish a system for local and remote streaming. I went to bed on the 12th March with a broad grin on my face, having just heard the effects of adding the final 2 SR Galileo network cables to my system. I awoke on the 13th after a good night’s sleep to find my ears feeling blocked, my hearing muffled, tinnitus in my right ear and my sense of balance completely gone. 2 weeks later I was given a diagnosis of Sudden Sensorineural Hearing Loss, essentially a failure of the cochlea and associated labyrinth, usually mediated by interrupted blood flow due to viral or vascular causes.
As a result I underwent a series of audiology tests, which resulted in the fitting of a pair of hearing aids. The fact that I’ve lost hearing entirely in one ear means that the stereo illusion, fundamental to hi-fi, no longer works for me, so listening to hi-fi is no longer interesting. However I still listen to music but now via the visual medium which provides my brain with the missing directional information. Naturally I wanted to compensate for my loss of hearing so I did several things:
1. I arranged a micro-suction wax removal to ensure that what hearing I do have is optimised. Just to mention at this point that candling is neither reliable nor safe and should not be considered unless other, modern techniques are not available, as may be the case in less developed countries. Likewise ear drops is another popular treatment that can cause as much or more harm than good.
2. A sight test to ensure my vision is 20:20
3. Hearing aids
As a former audiophile I obviously wanted as good hearing aids as i could obtain. Like hi-fi, there are several manufacturers, all offering their own cocktail of both common and unique features.
As luck would have it, the audiologist practice my ENT specialist referred me to has two of the most customer oriented, patient individuals I have ever come across. Starting out with balance tests, tympanometric tests to check for eustachian tube disfunction and hearing tests, they developed a full array of diagnostic data about my ears. From there its was a matter of selecting a pair of suitable hearing aids and setting them up according to my prescription.
The first thing to know about hearing aids is that some degree of hearing must be present in order for it to be ‘aided’. Essentially a hearing aid is like a graphic equaliser, boosting those frequencies where deficits exist. The most common deficit is a rolling off of sensitivity as frequency increases. In older adults there may be an across the board general lack of sensitivity that gets worse with increasing frequency. The audiologist should set up the hearing aids to compensate for the losses in each ear, such that the patient achieves a flatish response between say 500-8000 Hz. All the hearing aids I am aware of are digital, so have a considerable amount of processing capability. Manufacturer’s use this capability to create specific performance characteristics in firmware designed mainly to minimize noise and enhance speech cognition. Specific programs can be developed to enhance different listening situations, for example listening to conversations in noisy restaurants, in groups, listening to music, driving in a car etc. In addition, most digital aids are now equipped with some type of Bluetooth to allow streaming from devices like smart phones, iPads, TVs, specialist microphones, in-car entertainment systems and the like.
Typically each manufacturer offers a range of aids, ranging from the simplest, most economical,
with least processing power, to top of the range flagships with a wide range of features and controls. Many aids offer control of volume, balance, tone (sharp to soft), directionality etc. via a smart phone app. Batteries may be rechargable or replaceable, so battery life is an important feature. A couple of tops aids I tried struggled to produce more than 12 hours service before requiring a recharge, which is really annoying when they start running out of juice mid-evening.
By far the most important aspect of any hearing aid is the audiologist who sets them up for you. Hearing aids can be purchased cut-price off the web, but the chances that they’ll do a proper job are slim to none. There are many different types and degrees of hearing loss. Ear canals are of different shapes and have different acoustical properties. The aids themselves are designed to be configured by a specialist and matched to a user’s prescription, so first and foremost, find a really good audiologist. Then there’s the aspect of hearing aids and hi-fi. Hearing aids do not offer full frequency response, rolling off very early in the bass and extending up to around 8KHz in the treble. In order to hear deep bass, the hearing aid must allow low frequency pressure waves to pass the hearing aid in the ear canal and reach the eardrum with as little attenuation as possible. Given that all naturally occurring sounds above a certain amplitude reach the eardrum, the hearing aid is going to introduce a delay between natural sounds and those amplified by the aids. The longer that delay, the more unnatural the hearing aid will sound. Of all the 7 sets of hearing aids I evaluated, Widex offered the fastest response (minimal delay) and this can be heard, but in my opinion there’s so much more going on with the aids in terms of processing that this is only one of several important differences between the various aids, so while its an important aspect, its not the only one.
So having evaluated flagship models from 6 different manufacturers, my take away was that the second most important aspect in making a good selection of hearing aid is to understand where your priorities lie and pick the best hearing aid for that/those job(s). Due to my type of hearing loss I need hearing aids all the time and I need them to hear everything, so my choice was based on the aids that offered the best speech comprehension in all circumstances, including streaming of phones and televisions. Battery life and wearer comfort were also major considerations. This will certainly be different for someone else, depending on both their type of hearing loss and their priorities. As far as I have been able to ascertain, there is no such thing as ‘the best hearing aid’, only the best hearing aid for you. And to achieve maximum success you need an audiologist who is willing and able to let you try several different brands and is happy to set them up for you. It turns out that buying a hearing aid is no different than buying a pair of loudspeakers. Some will make you happy and others won’t and the only way to ensure the former is by choosing a great audiologist and comparing different brands over reasonably extended periods until you find devices that best fit your needs.
Of course this isn’t advice intended for everyone. It’s advice intended for people who care passionately about the quality of sound they listen to.