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New 28-bit DAC coming out.

Wolf11Man said:
Owners of high-resolution measuring instruments will surely be overjoyed that there is finally an audio device that is better than anything they can measure.
I'm overjoyed that there is finally a solution to a problem I never had and never will have.
This saves me a tremendous amount of money and many sleepless nights.
Sometimes it's actually advantageous to be too stupid to understand every new technological development.
My limited knowledge tells me it's useless for the audio field I use. Please don't correct my subjective, simplistic viewpoint. I can't afford such a correction.
Click to expand...
However limited, your knowledge is correct.

There are many audibly perfect DAC's - some at very low cost. however much better this one is measurably - it can't be more audibly perfect that those.
 
KSTR said:
Interaural level difference at low frequencies where the obstacle (the head) is small compared to the wavelengths is purely a function of the distance difference from the source to the individual ear. Sound pressure in the free field goes with 1/distance and hence if the distances are small then level difference starts to become signficant. I leave it to the reader at what approximate distance from the head we get a 10% (1dB) level difference), may AI help if you want an answer quickly. You'll might surprised.
Click to expand...
A1 says...
"At roughly 1.5 meters from the head, you get about a 1 dB (≈10%) interaural level difference purely from distance.
Intuition:
Closer than ~1.5 m → ILD grows quickly
Farther away → distance difference becomes negligible → ILD shrinks"
 
markus said:
A1 says...
"At roughly 1.5 meters from the head, you get about a 1 dB (≈10%) interaural level difference purely from distance.
Intuition:
Closer than ~1.5 m → ILD grows quickly
Farther away → distance difference becomes negligible → ILD shrinks"
Click to expand...
Surely it depends on the angle to the sound source compared to where you are facing. Exactly to the side will be maximum difference - directly in front difference will be zero.
 
With r being the distance to the closer ear, and d the projected path length from ear to ear and x being the SPL droop ratio (<1), we have
x = 1/(r+d)] / (1/r)
==>
r = d * x/(1-x).

For 10% (x=0.9) and d=0.25m we get:
r = 0.25 * 0.9/0.1 = 2.25m.

Therefore, "roughly 1.5m" doesn't appear to be right.
 
KSTR said:
With r being the distance to the closer ear, and d the projected path length from ear to ear and x being the SPL droop ratio (<1), we have
x = 1/(r+d)] / (1/r)
==>
r = d * x/(1-x).

For 10% (x=0.9) and d=0.25m we get:
r = 0.25 * 0.9/0.1 = 2.25m.

Therefore, "roughly 1.5m" doesn't appear to be right.
Click to expand...
D would be much closer to .15m. I have a big head and it’s 178mm. Which brings it to 1.35 if the speaker is perfectly lateral.
 
I measured 25cm on my head for the shortest path which is pretty average I would think. This is not the ear-to-ear direct distance, actually it is half of it plus (roughly) 1/4th of the head circumference. The path that a flat wavefront incident on one side has to take until it hits the other ear, the ear.
 
This has been an incredible hype train , someone please send it to amir :D curious minds wants to know what the fuss is about
 
KSTR said:
I measured 25cm on my head for the shortest path which is pretty average I would think. This is not the ear-to-ear direct distance, actually it is half of it plus (roughly) 1/4th of the head circumference. The path that a flat wavefront incident on one side has to take until it hits the other ear, the ear.
Click to expand...
Ahh. So I probably just replicated the AI answer by taking the difference between the ears.

Seems to me, given the complications of bone conduction, stereo, and non-lateral start points, plus the complication our aural processing brings to the issue, I think it might actually be simpler to run a statistically significant trial than reasoning it out.
 
IPunchCholla said:
Ahh. So I probably just replicated the AI answer by taking the difference between the ears.

Seems to me, given the complications of bone conduction, stereo, and non-lateral start points, plus the complication our aural processing brings to the issue, I think it might actually be simpler to run a statistically significant trial than reasoning it out.
Click to expand...


Very much this.
 
KSTR said:
With r being the distance to the closer ear, and d the projected path length from ear to ear and x being the SPL droop ratio (<1), we have
x = 1/(r+d)] / (1/r)
==>
r = d * x/(1-x).
Click to expand...
SPL drops with the inverse square law.
 
SPL = Sound Pressure Level, which is the log of Sound Pressure.
Anyone with a basic understanding of physics knows and understands that sound pressure (and thus sound pressure level) goes with 1/r, not 1/r².

You are not dealing with morons here, so y'all stop trolling, please.
 
popej said:
SPL is a value relative to reference level and it is log of square of sound pressure. Please read definitions here:

Sound pressure - Wikipedia

en.wikipedia.org en.wikipedia.org
Click to expand...
Sure. Log10(x^2) = 2*Log10(x), that's why the SPL deci-Bel scale factor is 20, not 10.

But this squaring has nothing to do with the inverse proportional law, quoting same Wikipedia article:
"When measuring the sound pressure created by a sound source, it is important to measure the distance from the object as well, since the sound pressure of a spherical sound wave decreases as 1/r from the centre of the sphere (and not as 1/r^2, like the sound intensity)"
 
KSTR said:
With r being the distance to the closer ear, and d the projected path length from ear to ear and x being the SPL droop ratio (<1), we have
x = 1/(r+d)] / (1/r)
==>
r = d * x/(1-x).

For 10% (x=0.9) and d=0.25m we get:
r = 0.25 * 0.9/0.1 = 2.25m.

Therefore, "roughly 1.5m" doesn't appear to be right.
Click to expand...

So the effect is negligible at 2.25m (which is probably closer to typical listening distances), and not 1.5m? I’m not sure, just wondering whether this has ever been thoroughly investigated.
 
It just shows that localization perception is also based on level, ILD at work. Together with ITD this allows bass and even very low bass to be perceived as directional just as any other frequency range
While actual speakers will be seldom closer than 1.5m, nothing stops us from rendering phantom sources at closer distances, using crosstalk cancelling. This is tricky with low bass but not totally impossible.
The main point was debunking the myth that low bass < 80Hz cannot be localized and thus a mono sub can cover all possible scenarios. It can't.

And now back to thread topic again.
 
KSTR said:
Sure. Log10(x^2) = 2*Log10(x), that's why the SPL deci-Bel scale factor is 20, not 10.

But this squaring has nothing to do with the inverse proportional law, quoting same Wikipedia article:
"When measuring the sound pressure created by a sound source, it is important to measure the distance from the object as well, since the sound pressure of a spherical sound wave decreases as 1/r from the centre of the sphere (and not as 1/r^2, like the sound intensity)"
Click to expand...
Well, a bit confusing. Treat it like this: either use 20 coefficient for log of SP or use square, when doing calculations directly in SP. You forgot about square in your previous estimations.
 
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