On Tuesday, 17 January 2017 20:38:11 UTC, NY wrote:
"Tim Watts" wrote in message
...
On 17/01/17 16:25, whisky-dave wrote:
Personally - I buy CDs and rip (carefully with software that retries
errors rather than skips), then encode lossless, plus a second max
bitrate MP3 for and devices that cannot handle lossless.
Where we should be right now is being able to buy digital lossless media
at better than 44kHz sampling...
44.4kHz was a compromise between quality and play time. It was a very good
compromise, but we might as well go a little better now there's no reason
not to.
I think that 44.1 was chosen to be sufficiently good that only dogs and bats
would notice the limitations.
I doubt that I thought it was do do with what ADCs could do at the time.
PCs were 44.1KHz macs were 48KHz internally.
It is generally accepted that human hearing is 20-20,000 Hz
(https://en.wikipedia.org/wiki/Hearing_range and many other sources) and
diminishes with age.
The problem there is if you had an instrument playing at 20Hz and one at 1KHz at equal amplitude the bandwidth is defined by half power so yuo wouldn;t hear the volume at the same level of 20Hz, 1K and 20K only the 1KHz would be at the correct power level delivered to the speakers.
and as you say, as you get older your hearing drops off especailly at the higher end so what you need to do in order to listen to the instruments at the level the artist originally played them at is to turn up the treble or extend the freqency range to ~22kHz, so 20K is no longer at -3db but at the same level as 1KHz is.
Nyquist's sampling rate says that to represent an analogue sine wave of
frequency f, you need a sampling rate of at least 2f.
for commercial use 44.1KHz was used pros used 48KHz.
So for 20 kHz, you need to sample at 40 k samples/sec. Allowing for
low-pass anti-aliasing filters that are not perfect, 44.1 or 48 k
samples/sec are sufficient. The exact values of 44.1 and 48 are for
compatibility with other systems (I forget the details, but I think they are
related to using PAL and NTSC video recorders with a few samples per picture
line for mastering early digital recordings).
So what would be the advantage of increasing the sampling rate? What would
the benefit be of being able to reproduce audio frequencies beyond about 20
kHz?
It's for mixing purposes I thought.
Maybe there is a need to increase the sampling depth to greater than 16 bits
(ie -32K to +32K),
Most musicians use 24 bits for their loops now.
though I think subjective tests have shown that there is
no perceived advantage,
I can hear the difernce between 16 bit and 24 bit.
Like soem peole can see a better and more gradients of colour especailly women it seems can better distiquish small diffencies in shades of colours.