The Black Hole......

And where did the 44.1Khz came from and not an integer like 44 or 45 ?

Story goes that analogue NTSC video recorders at that time could record 525 interleaved lines of which 35 where reserved, giving 245 usable lines at 60Hz
So 245 lines at 60Hz, packed with three 16 bits samples per line, gives a sampling rate of 60 × 245 × 3 = 44.1 kHz.

Only point is that NTSC did not work with 30Hz per full frame but with 29.97Hz.

Hans

And the 44.056 KHz sampling rate which results from the drop frame NTSC rate is what the Sony PCM-F1 (and other PCM to video units) uses. I still have a pair I use for digital stereo links around campus where I do not want the unpredictable latency, burstiness or factors out of my control which in general which is what you get using a web-AoIP link. Just run a piece of RG-6 and voila! There are much better ways to do it these days, but the PCM-F1 link has worked great for over 30 years, and it is paid for. I use a a Jensen video isolator to break any CM loops.

Amazingly the video output amps in the F1 can drive many hundreds of feet of RG-6 with no sync drop due to attenuation issues. This is hardly the usage Sony intended...

Cheers,
Howie
 
seems to be a casual disinterest in what looks to be the only real way to measure what’s been discussed here?

Reposted from earlier in this thread because it seems apt once again in response to this...

I think it is time to reintroduce this link:
Human hearing beats the Fourier uncertainty principle

"The top score, achieved by a professional musician, violated the uncertainty principle by a factor of about 13, due to equally high precision in frequency acuity and timing acuity" ...it does point to some very good reasons to go beyond 20K even if the ears not hear the notes directly.

I think you will find this can be attributed to (at least) the bispectrum being the foundation of our aural perception, rather than our hearing extending beyond 20kHz and our brains exceeding the Uncertainty Principle (or at least its equivalent in the time-frequency plane).

The ear and brain functioning as a (third order) bispectral analyser does not preclude the useful application of more easily represented, conventional (second order) spectral analyses, however, just that we might consider a dynamic trade-off between time and frequency resolution somewhat commensurate with the convergence evident in our perceptual apparatus.

In such analyses, there might even be found measures that identify oft-reported differences between transient and steady-state audible phenomena. Ohm's Acoustical Law (that the ear is insensitive to phase), for example, might only be an approximation, albeit a very useful one in most cases.
 
if I knew what I was talking about I wouldn’t be here...so I digress.

I only mentioned the slew rate thing because it kept popping up with digital brick wall filtering and how it’s tied to Nyquist limits etc.

btw....you fellers do see the question marks after I’m stating something.....means ‘I have no idea, is it at all relevant?’
 
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