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Re: [ARSCLIST] External A/D converter with AES/EBU output
From: Patent Tactics, George Brock-Nannestad
Jeff Carroll wrote
> As analogue archiving standards go, emphasis has always been placed on flat,
> unprocessed transfers.
----- what is recognized as FLAT transfers these days?
I see 3 possibilities:
1) taking the signal from the pickup cartridge, linearly amplified to the
maximum level tolerated by the A/D device
2) taking the signal from the pickup cartridge, linearly amplified and then
compensated by the inverse of the transfer function of the cartridge itself
when hooked up to this particular preamplifier
3) taking the signal from the pickup cartridge, as in 1) but amplified in
inverse proportion to the frequency from the corner frequency of e.g. 250 Hz
(thus taking into account the changeover from "constant velocity" to
FLAT would under no circumstances mean "using a de-emphasis curve to equalize
the pre-emphasis given at the time of recording" (for instance a high
frequency boost to reduce hiss at de-emphasized playback)
My clear preference is for 2) although that requires the step of calibrating
the pickup. 1) may work, but then the transfer function of the pickup must
also be recorded - again calibration.
3) I like the least, because the choice of corner frequency is pretty
arbitrary if you do not know precisely what it was at the time of recording.