The problem with USB is in relation to the low power source, not the generally accepted difference of the 24 bit digital theoretical limit(144dB) and the real world of 110-120dB.
The best convertors i've used(mytek/benchmark/lavry) are up around 118dB which is f'ing impressive.
anyways, this from Dan Lavry - designer of some of the finest convertors ever:
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...In other words, 24 bits is not just about the digits we use. Some of
those digits are "just there doing nothing". It is like counting real money with 4 digits for cents. Instead of saying $1.27, we say $1.2700. The right 2 digits are always 00.
Now, lets go into the computers world, With 5V analog supply
environment, instead of the +/-15V above (equivalent to 30VDC). We
must reduce the signal range by about 6:1 and lose about 15.5dB in signal to noise...
Another 2.5 bits gone...
That too is a terribly optimistic picture. That 5V from the USB bus or
other port is so dirty, that by the time you clean it, you are
probably starting at 3.3VDC, not 5V... and you are entering the 16 bit performance world. Do not feel bad. Most CD's are less than 16 bits in terms of signal to noise, and some of them are great sounding!
But, don't spend your money on BS hype. 24bit USB device for $200? You can not get real 24 bits for $200000. For reasonably low cost, you
will do very well to really achive 16 bits.
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Topic: usb or pcmia interface (Read 7100 times)