[78-L] stereo/mono and noise reduction

[Rodger Holtin]

Recently made a CD of some antiques for one of the kids at the university radio station and burned the wrong file for one of the tracks.  He noticed it was a lot noisier than the others.  True.  I usually record digitally in stereo then apply a+b= mono somewhere in the process of noise reduction and/or EQ tweaking before I call it done.  Anyway, we ripped that track to a computer, applied the a+b with his audio editor and voila! - quiet!  That is a lot more noticeable with headphones than monitor speakers, but still sometimes quite dramatic no matter how you're listening.
 
I picked up on that a+b trick back in the 1960's when I read some article about phase distortion in relation to 78s.  That's been decades ago.  For awhile I had a tuner that would mono a stereo FM broadcast and that would help even those noisy signals.  (I sure miss it.)  Can somebody give us a good description of how and why that works for 78s and/or FM?

Rodger

For Best Results use Victor Needles.

.