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Originally Posted by The Byre (GS)
It varies with the quality of the converters.
I often hear that higher sample rates are required if we are to hear music properly. Despite the rather obvious fact that our ears only go up to 18kHz at the very best for an adult and usually somewhere between 14 and 16Khz, (depnding on age, health and the amount of exposure to loud noise) and the fact that no studio mics go beyond 22kHz, people claim to be able to hear an improvement when listening to material recorded at higher sample rates.
At the same time, several scientific tests have shown that when the same material is played back at different sample rates (and where the source material was at the very highest rate possible) none of those tested could hear any difference between 192kHz and 96, 48, or 44.1kHz.
Many hi-fi companies and enthusiasts assert that the wider bandwidth and dynamic range of SACD and DVD-A make them of audibly higher quality than the CD format. However many carefully controlled double-blind tests with many experienced listeners showed no ability to hear any differences between formats. Therefore the perceived quality has nothing to do with additional resolution or bandwidth.
And yet even I can hear a difference on some occasions! So what is going on?
In general, yes it does sound better, but not because we need the extra bandwidth or dynamic range to appreciate the music, but because of the inadequacies of earlier equipment.
Earlier converters created all kinds of distortion and even self-generated noises at the higher frequencies. One DAW even had a constant whistle at about 18kHz. This lead to all kinds of unpleasant artifacts and distortion in the upper frequency ranges. The worst offenders were DAT and ADAT machines, cheap computer sound cards and even some prestige converters.
This upper range distortion was what some people called digital sharpness, or digital harshness. In reality, it was just good, old fashioned distortion. When ever I mastered a piece of music that had been recorded, using an older box, the spectrum analyser would show the line 'sticking' at the top somewhere above 17kHz. This is when I became interested in the subject and dug to find out more.
Now, if you double the sample rate to 96kHz (or 88.2kHz for a CD) when making the original recording, then all that distortion taking place between say, 14kHz and 22kHz is moved to between 28 and 44kHz - i.e. out of hearing range.
Suddenly, all that upper distortion vanishes and we come to the conclusion that a 96kHz sample rate is superior to 44.1kHz.
Very often, it is not even the converter's fault, but can be the result of poor cabling, or interference from other equipment. Discussions with hardware engineers would suggest that clocking was a major problem for some systems.
So if you want to play it safe, record at the higher rate to ensure that no distortion caused by jitter or other gremlins come in with the original material, but the improvement is not because you have golden ears!
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