On 19/10/2012, Tom Fine wrote:

> We may have three different but equally effective MO's going here.
> Mark's method harkens back to the days of 1630 mastering, where you
> needed to find and set your peak levels before you made your A-D
> transfer. This was definitely how my mother operated with the Mercury
> CD's; she and her engineers knew to set the dcs ADC input level where
> digital zero basically equalled Audiotape 1960 brown-oxide saturation,
> because in almost all cases, there would be an fff peak that would be
> at or near saturation (Ampex 350 playback electronics have more
> headroom than brown-oxide tape, so electronic distortion was not a
> consideration). There are technically some very brief digital
> over-zeros on some Mercury CDs here and there, but no one has ever

The Gershwin piano concerto is an example.

> returned one because it won't play or it sounds lousy. The
> manufacturing plants tolerated them because their own QC people
> couldn't hear anything that would lead to merchandise returns. To be
> honest, I'd be more conservative with levels if I were doing it today,
> but I'd be working in 96/24 and because I was working in a DAW, I'd
> have a chance for as many "do-overs" as I wanted. When you're
> transferring to a linear medium and the studio clock is running to the
> tune of dozens or hundreds of dollars per hour, you behave
> differently!
> Richard's MO is very modern and I'd say on the cautious end of
> conservative. However, with a very-low-noise signal chain, it should
> work and I'm sure Richard has done his own noise-floor analysis and is
> OK with the results. His long list of satisfied clients speaks for
> itself.
> My MO is somewhere in the middle, but only because I came up using
> linear media and learned to maximize s/n (ie keep levels as high as
> possible without electronic distortion or noticeable tape saturation).
> Since I started transferring at high-resolution about 10 years ago,
> I've dialed back on input levels significantly, landing where I
> described in my earlier post this morning. Once again, if I were doing
> more aggressive DSP, I'd be more conservative on the transfer levels
> because aggressive DSP can severely effect maximum level and dynamic
> range, especially EQ because you are undoubtedly adding or removing
> something that has an out-of-phase component somewhere, and that can
> greatly effect peak level, ambient noise level and overall levels.
> Observe how much levels change on a 78RPM transfer as you experiment
> with different rumble treatments. Same to a lesser degree with LP
> records and also with mass-duped tapes. In theory, master tapes
> shouldn't have rumble problems that need treatment.

Don Cox
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