herbie@watdcsu.UUCP (Herb Chong, Computing Services) (10/17/84)
I apologize for the misunderstanding of delta-modulation. I was
remembering an article in Audio a few years back describing it.
I do remember that dbx had a lot of problems initially trying to
solve the breathing problem with the device. Does anyone know how
they did it?
A few random thoughts about dynamic range of CD's. I said a while back that
120 dB was a target that some people around here were aiming at. I also
said that someone was working on a compander to do that for a 16-bit
linear system like CD's. Well, a single channel was constructed about
6 months back and tested. Breathing was not very bad because of the
low 1.3 dB/dB compression ratio, but, as expected, noise was the major
problem. This project was wire-wrapped just to see if it would actually
function and it did. I don't have the catalog number of the VCA's used,
but they were about $100 each in small quantities and their specs were
in line with what was required. I will dig up the technical report
and follow up later. The people who worked on it still think that 120 dB
dynamic range is required for the system mostly to protect the recording
engineers from incorrect level settings. Having done no live recording,
of my own, I can't say. The leader of the project has, with both analog
and digital recorders, under relatively controlled and uncontrolled
situations. He sees it as a safety blanket for slightly too high
recording levels.
Herb...
I'm user-friendly -- I don't byte, I nibble....
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BITNET: herbie at watdcs,herbie at watdcsunewton2@ucbtopaz.CC.Berkeley.ARPA (10/19/84)
So now we need *120 dB* dynamic range "to protect against incorrect level setting by the recording engineer"!!!! Land sakes, what's been protecting us during the dark night of the analog era? Did I hear someone say "limiters"? Let's get real, folks. Maybe its time to take up another hobby if the improvements offered by 16-bit digital are so, um, disquieting. I suggest amateur beam weapons building-- THERE's a field not likely to be pre-empted anytime soon by success...