Comment by masklinn | Hacker News Reader

Comment by masklinn | Hacker News Reader

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> Does the author actually have a reason why analog would possibly be better, other than giving consumers choice?

Duh no. And this article does a disservice to itself, as it looks like there could be a real issue of fidelity in the digital chain[0]. Bluetooth is known to cause issues (lag, bandwidth variations, …), and the processing chain might be problematic:

> the digital processor samples incoming sound at a rate far lower than that of an old CD player

I don't know if there's any truth to it, but it should certainly be investigated and if true fixed. It might also be that the perceptual models used in these hearing aids are not correct for, well, hearing aids.

[0] though some of the complaining could be a question of habit, the wearer's old hearing aids had a coloration to which they'd gotten more and more used, the different profile of the new ones is jarring even if it might be more correct

CD sampling is 44.1kHz. 22.05kHz is used in plenty of HAs. I haven't seen anything lower (but wouldn't be surprised to learn otherwise)

22kHz sampling isn't a problem in practice as:

- HAs focus on speech comprehension, not music. Speech doesn't high much content above 5kHz, so even 22kHz is double the Nyquist rate.

- Music is perfectly enjoyable at 22kHz (but obviously better at 44kHz)

- People getting hearing aids have hearing loss, and the majority of hearing loss is in the high frequencies

To add to this, most middle age adults can not hear above 15khz and threshold is very high at 11khz, especially if they were exposed to high sound levels in youth. Virtually no one can hear above 22khz.. if you ever hear people saying they can it is most likely bs.

People often tell stories about playing a sound or being in a lab etc. they think they heard above 20khz, but mostly likely what happened is whatever inevitable non-linearity exists in their playback chain acts as a mixer creating frequencies well in the easily audible range.

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