[78-L] shifting phases

[William A. Brent]

recently I was given a vast amount of raw transfers to DAT of some 
nice 40's-50's vocal material.
the records are long gone, but the original owner transferred all of 
them (about 2500) between 1992
and 2002. His plan was to restore as many of these as he could. at 
some point, some one must
have told him that recording these old mono platters with a stereo 
cart - out of phase - was a good
idea.

naturally, those recorded in-phase can be blended to mono (assuming 
both sides of the groove wall
are worth using) and some of the noise will be eliminated. If I do 
that with the out-of phase recordings,
all that will be left is the noise (and whatever material only exists 
on one side of the groove or the other).

of course I can reverse the polarity on one of the tracks, but I was 
wondering - is there
some reason to have recorded these "out-of-phase" in preparation for 
restoration?

thanks