John Curl's Blowtorch preamplifier part III

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SR-1 measurements

https://www.innerfidelity.com/images/StaxSR1.pdf

Re impulse and step response, all headphones have issues. Oscillating impulse and step response.

The whole list

Headphone Measurements | InnerFidelity

I tried another, smaller headphones. The impulse response is faster - smaller transducer. Shape of positive and negative impulses is the same, so we may speculate if we hear phase inversion in some cases. However still the headphones are unable to follow the input impulse - no wonder.

P.S.: test file to test absolute phase audibility attached. Same impulses, positive and negative. No L/R shift. My ABX result is ZERO.
 

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But look at headphones, it is not perfect but it can capture 3D information even tho all sound coming from the same direction. The ears do not fully care about the direction, it only cares about the chunk of sound information. By this mechanism, ears can be fooled or confused, because it HAS TO judge where the sound source is even if the information is not there.
To a degree, but this sounds like mainly conjecture, it should be easy to test, the sound of a plane or geese flying across the sky, how does the brain interpret that played on headphones?
 
P.S.: test file to test absolute phase audibility attached. Same impulses, positive and negative. No L/R shift. My ABX result is ZERO.
Pavel, did you try this: John Curl's Blowtorch preamplifier part III.

Testing with impulses is difficult, I agree. Using a high passed step is more revealing as it contains sufficient low frequency energy.

Re HP measurements, the only way to do that correctly is to compare the response with a free-field incidence on-axis (to the ear, not the nose ;-), using the same dummy head with a mic in the ear canal.
 
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Is there any point asking whether you peeked, I thought you heard it? My chromebook can't show the waveform, of course I could be lying....

Well, the default player for wav on my laptop did show the waveforms, so I knew straight away... And, I'd guessed what Pavel had done with the impulses. I could hear no difference with the ITD pairs, but that could well be the laptop affecting it. I could hear a difference with the inversions but then I could see that too so I'd declare that as not a good test!
I suspect - as Pavel subsequently showed, that the earbuds / windows almost certainly smeared the difference with the ITD delays. But then most systems will, I think that's part of Pavel's point.
 
Testing with impulses is difficult, I agree. Using a high passed step is more revealing as it contains sufficient low frequency energy.

As you know, the test impulses used have flat frequency spectrum from 20Hz to some 4kHz. -6dB at 10kHz, deep notches at 16, 32 and 48kHz ;).

However I know what you mean.
 

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To a degree, but this sounds like mainly conjecture, it should be easy to test, the sound of a plane or geese flying across the sky, how does the brain interpret that played on headphones?

If you close your eyes, how will your brain interpret the sound of a plane or geese flying across the sky? May be it is not as obvious as one would have assumed?

Regarding headphones (i don't like/use headphones), because the position of the drivers/eardrums are fixed, the single mic idea has been implemented in binaural where mics are placed in dummy head. Why not try it by yourself?

If a mic is good, placed slightly above a drum, the cymbals should normally be at higher position than the drums and is recorded by the same mic. Reproduction of this recording should show that the cymbals are at higher position than the drum, like we often hear from a recording.

Regarding techniques to engineer effects digitally for headphones, i have no information. But once somebody showed me a site where we tried effects to our various headphones. I don't remember the site but i was surprised how they can move sound around like that. BTW, I listened with mono speaker the song Colour To The Moon by Allan Taylor. At the beginning there's HF sound moving around. When the speaker was on my right side the sound could be made to come from my left. :confused: :D

YouTube
 
If you close your eyes, how will your brain interpret the sound of a plane or geese flying across the sky? May be it is not as obvious as one would have assumed?
Pinnae transform mostly
Regarding headphones (i don't like/use headphones), because the position of the drivers/eardrums are fixed, the single mic idea has been implemented in binaural where mics are placed in dummy head. Why not try it by yourself?
I didn't realise you meant binaural recordings, ok
If a mic is good, placed slightly above a drum, the cymbals should normally be at higher position than the drums and is recorded by the same mic. Reproduction of this recording should show that the cymbals are at higher position than the drum, like we often hear from a recording.
How do you work that out?
Regarding techniques to engineer effects digitally for headphones, i have no information. But once somebody showed me a site where we tried effects to our various headphones. I don't remember the site but i was surprised how they can move sound around like that. BTW, I listened with mono speaker the song Colour To The Moon by Allan Taylor. At the beginning there's HF sound moving around. When the speaker was on my right side the sound could be made to come from my left. :confused: :D

YouTube
Yes, phase, frequency response manipulations can fool the ear by emulating pinnae transform etc
 
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