[Gwc-general] restoration of dynamic range in vinyl recordings?

[David B. <da...@ja...>]

Hi, I'm new to the list and have a question that is not specific to GWC, 
but is applicable to digital audio restoration of vinyl recordings.

In the course of digitizing "modern" stereo 33 1/3 RPM LPs, I have 
noticed what seems to be a consistent dynamic range compression 
characteristic applied right at the top of the loudness range.   It is 
very apparent on the sound card VU meters as I record, and reminds me of 
what FM broadcast stations do to ensure they avoid overmodulation.  Same 
thing here with grooves, I suppose - and I am assuming it's not just my 
phono cartridge (Audio-Technica 3003) or preamp that's doing it.

My question is, does anyone know of anything like a "standard" expansion 
characteristic that might be applied to these recordings, with the goal 
of approximating the original dynamic range?  I'm about to start doing 
some "by ear" experiments, but just wanted to check first.

Hm, something like this might even be a nice added feature for GWC at 
some point, if it really works... :-)

Dave