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points by dugidugout 2 days ago | 0 comments

I think there's a misreading at the root of this. The "70 Hz" in the post is the modulation rate from the TMTF, not an audio frequency. The TMTF measures how fast loudness can flutter before the flutter is undetectable. It isn't a pitch or discrimination test. From the post, OP does discriminate, somewhat, above 70 Hz and says they can't judge pitch direction at all, so there is no 20–70 Hz "working band" to retreat into.

I agree with the broader instinct that OP deserves a clinician to help with the hardware side (having their map and device parameters alone would go a long way), but it seems OP is taking any step they can towards this effort.

I regret that I don't have anything to actually add towards helping OP. Their posture towards understanding is refreshing and the Lean bit reads to me more as a cute testament to that than anything eerie or strange.

[–] mk_stjames 2 days ago

I re-read it and looking more at the tests and... I think you're right but also maybe OP is confused about how the audio spectrum works in general then, because they themselves talk about this 70hz shelf in the same breath as human vocal ranges etc -- that isn't amplitude modulation frequency. But maybe there is just something here that is lost in translation or I'm just not getting the real purpose of these test measurements.

If I'm a bit more imaginative on this 2nd read of their 'experience' of these tests it seems that maybe yes, they hear 'something' at higher frequencies but it just just broadband noise- broadband noise mind you, is, all frequencies... so I was confused at how someone could say they 'don't hear anything above 70hz' and yet can somehow hear 'noise' at '2000 hz'. But it is dawning on me that the implant / associated driver hardware may simply be 'saturating' when the spectral content of audio is too large at all those frequencies, and OP can actually 'hear' something, but it just blurs into white noise when the spectral power is too high - kinda like there is a massive amount of reverb being applied to everything over 70hz.

But again they talk about their struggles with understanding voices and whatnot but if they are hearing parts of music at all then they could be hearing people' voices shifted into bands and toned down to amplitudes that helps them. Like, clinicians with experience here should be helping with this and it is kinda insane that this person is attempting to discern anything themselves.

The exposition is strange and again that could just be the translation and writing style but some of those little bits and just the way I've seen some people literally start spiraling when they start to pair-autodiadict with AI - coupled with the fact this is a medical condition and a life-altering disability - along with a few other small oddities in this post - make me kinda worried there is a lot more to this than posted and OP may need other kinds of help with their situation.

[–] dugidugout 2 days ago

> ... maybe OP is confused about how the audio spectrum works in general then, because they themselves talk about this 70hz shelf in the same breath as human vocal ranges etc -- that isn't amplitude modulation frequency.

In a CI, voice pitch actually _does_ arrive as amplitude modulation at the F0 rate. The processor keeps only each channel's envelope, and the harmonics of a voice that share a channel beat against each other at F0. So a 70 Hz flutter ceiling and vocal ranges do belong in the same breath.

> ... so I was confused at how someone could say they 'don't hear anything above 70hz' and yet can somehow hear 'noise' at '2000 hz'. But it is dawning on me that the implant / associated driver hardware may simply be 'saturating' ...

The TMTF carrier was noise by design, so above 70 Hz the flutter vanished and the noise that was already there is all that's left. No saturation is needed to explain it. The “wind” in SRD is what a spectral ripple sounds like through limited spectral resolution. This is a resolution problem, not a level problem.

> The exposition is strange and again that could just be the translation and writing style...

This paragraph was why I initially made a comment. They were radically honest with their methodology and obviously living inside the problem. OP is actually reading this thread, for what it's worth.

[–] jdanford 2 days ago

Sorry, but what is the point of using an LLM to generate replies like this?

[–] dugidugout 1 day ago

What is the point of using your account to generate replies like this? Even your use of "Sorry" is obviously vapid. Try addressing my comment or don't participate.

[–] mi-rae 2 days ago

Thank you for pointing out that the 70 Hz is a modulation rate, not an audio frequency. That's exactly right. I wish I could find someone in Korea to help me with the hardware side, but no matter how hard I've tried to persuade people, I've mostly been ignored. As for the Lean part, I wasn't sure whether it was really necessary. I've never been part of academia, so I'm still very clumsy and amateurish at this. Even so, I'll keep doing my best to find someone who can help with the hardware side. Thank you for your kind words.