This is a very convoluted method to recover audio from non-RIAA records. Gary Galo has written a
very good article about the science of grooved-media recording and playback curves here:
http://www.smartdevicesinc.com/riaa.html
Gary has also written for ARSC Journal advocating analog playback and EQ of grooved media, rather
than "flat playback" and software EQ, and has specified the technical reasons why analog EQ works
differently from DSP EQ.
Keep in mind that exactly what recording curves were used on almost any 78 record is not set in
stone, and that even if a specific curve was specified, the antique equipment was generally
non-precise by modern standards.
In any case, after many transfers of 78's (and pre-RIAA LPs), I am a strong advocate for doing as
much in the analog realm as possible, saving the digital realm for things like file-storage, CD
authoring and the like. Minimal but time-consuming DSP is useful, specifically in the area of tick
and pop removal. I do all of this by hand, having found no automated software to be foolproof and
thus time-saving. A waveform editor is a wonderful thing and ticks and pops can be near-silenced or
completely silenced if you know what you are doing. As for background noise, I prefer to do this in
the analog realm, tuning turnover and rolloff to ear (what makes the music sound most natural with
the least background noise, that's my cardinal operating principle). I also apply moderate secondary
EQ when needed. DSP is useful for removing 120hz or 60hz hum, and also very useful for removing
low-frequency rumble (just make sure to tune it so you're not rolling off the lowest notes in your
program content).
Despite elaborate claims by software companies, I have yet to find any "select and run" software
that "cleans up" transfers of analog material without removing a good bit of the content. If you
minimalize the automated stuff enough to have no musical content in the removed-audio signal (which
you can monitor in most of this software), it's doing very little and leaves in material that needs
to be manually removed or EQ'd out, so I prefer to just do that in the first place. BTW, I find this
to be true also with blanket-applied hiss removal for tape transfers, by the time you use it
conservatively enough not to remove top end, echo tails and air and space around instruments, it's
not removing any hiss. What can help, especially with mass-duped tapes, is to not assume that they
were recorded with a very strict adherence to the NAB curve since high-speed duplicating was an
inexact thing back in the day. So trim the NAB high-frequency control to your ear, maintaining the
correct balance of instruments, natural sound on the instruments and listening carefully to preserve
reverb tails and air and space. I usually find you tame the audible hiss without losing any content,
and you're taming it at the very frequencies where it's most annoying. I know, tuning EQ to ear is
anathema to some, but I'm telling you the results can sound great.
One man's experiences, opinions, etc.
-- Tom Fine
----- Original Message -----
From: "Chris J Brady" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, April 10, 2012 6:24 AM
Subject: [ARSCLIST] Recording_78rpm_records
For those who like rescuing old 78s and even cylinders of folk music etc. from junk shops etc. and
then digitising them there is some very useful info. here:
http://manual.audacityteam.org/man/Recording_78rpm_records
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