Pitch Perception as a Function of Amplitude?

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I'm not sure if this is the right forum, so I apologize if there was somewhere better to put it.

Does anyone have any personal experience with pitch perception changing as a function of signal intensity?

I've found a few studies suggesting that it's normal for people to perceive pitch as falling when amplitude rises.

Is there a reason for this that anyone knows about?

Anyone else upset by this phenomena?
 
Does anyone have any personal experience with pitch perception changing as a function of signal intensity?

Never had that sensation when listening to live music. By how much is the pitch perceived to change? as much as a semitone? That would be upsetting.

Sudden movement of an organ swell pedal would be an excellent live music test. I shall try to remember for next Tuesday. Long reverberation time (eg cathedral) may point up that phenomenon with beat notes.

I have heard this phenomenon quite often, but I have never found any explanation ...
Can you tell us where you have heard it?
 
From 40 to 90 dB the effect is a downtuning of 20 cents at 200 Hz, and 60 cents at 1kHz. 100 cents is a semi tone.

From 70 to 120dB the shift downwards is exaggerated even more, over 1.5 semitones.

My ears are sensitive to pitch changes of 0.06 Hz at 500hz on a good day, and .125 Hz at 500 Hz on a bad day. This corresponds to 0.2 cents and 0.4 cents respectively.

The change in pitch lasts the duration of the high volume period, and does not normalize during listening.

I’m also more sensitive to flat notes than sharp notes, but I’m pretty sure that is normal.

I personally doubt that an organ could produce the dynamic range necessary for this test.

For me, headphones with a sine tone seem like the easiest way to demonstrate the effect. Adding harmonics seems to make it harder to perceive the change but I haven’t actually done ABX testing.
 
You can use this to test your sensitivity both to pitch in general and pitch as a function of intensity:

Adaptive Pitch: Measure your pitch perception abilities

I just took it again (to make sure I wasn't spouting BS about my pitch perception ability) and I got down to .1875 Hz at 500. No caffeine or red food coloring yet today, plus I was using open back headphones while my wife was watching TV.
 
Practical use, no... I wouldn't say so.

I grew up a musician, but I had a rather weak perception of "perfect pitch"... very dependent on the source tone timbre.

As far as what I might do with this information; I'm thinking of building an experimental DAC that uses a sort of Shannon-Whitacre filter with an added pitch component. I have experience with FPGA programming, so maybe it will be a weekend project of some sort.
 
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Interesting subject. Can't say that I've noticed the effect, but my sense of pitch isn't very good. I do know that as music get really loud, our ability for fine pith perception gets worse. That's one of the reasons that louder sounds better. The louder than band, the less you hear how badly they play. :p
 
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