A sucky process, basically....and whenever it was used--a proprietary process--it got credit. Atlantic & A&M seemed to use it more than anyone else, but it fell out of favor, thankfully....
You've got it...wish I had a prize to send. I know it is a phase process where they put one channel 90 degrees out of phase, in order to keep "compatibilitiy" (whatever that meant). All I know is, if you listen to a CSG-processed recording over near-field speakers (like computer speakers) and headphones, it is almost like listening to something that is out of phase. Which it is...but only about halfway. (180 degrees phase difference is considered "out of phase"; 90 degrees is halfway there.) And unless there is an un-CSG'ed master somewhere, there is no way to undo the CSG process short of remixing an album!
Two things I didn't find answered in the other threads . . . what in the heck is "CSG Processed Mono"? I have some mono 45s labeled as such. And why can't the stereo version be undone by delaying the one channel so that it's back in phase?
1/2 out of phase. You could flip channels from now until forever and it would still be out of phase. It's unfix-able; I've tried.
CSG means compatible stereo grooves or something like that. IIRC, it's an interchangeable format (mono/stereo), but I don't know how that relates to your record. Someone else might now more about this.
Compatible Stereo Generator designed to play mono with a mono cartridge and stereo with a stereo cartridge.
This is an Atlantic DJ copy that should be folded to mono for radio airplay. CSG is the process that Atlantic was using at the time for mono and stereo 45's(well, some 45's, anyway), and some of their promo Lp's were processed the same way. If the stickers says mono, unless someone has a copy to verify otherwise, one should presume it'll be mono.
Pat; could you please start taking you meds again? I lost it on "Gnash", then I read "Hung"...everyone one in the office wondered why I was laughing so hard in my office.
From what I read, when you "fold back" a stereo recording back into mono, anything in the "center channel' gets boosted 3-to-5+. Play an early stereo Beach Boys recording in mono and the backing track in the center overwhelms the vocals on the sides. Any 60's stereo recordings with the lead vocal mixed hard right or left gets buried in mono. The CSG process was a primative method of enabling AM mono stations to play stereo records without this "build up". It threw the center channel out of phase, which worked played in mono, but played in stereo it made a mess out of the stereo image, and also muddied the sound. I dont recall many companes using it besides Atlantic, MGM, A&M (on singles) and Warners/Reprise on thier albums. My vintage LP of the Association's Greatest Hits was processed with CSG, and sadly when Warners reissued it on CD in the 80's, they used the same processed master. It was a Revelation to hear the original stereo masters on the Japanese reissues and the Rhino 2-CD comp.
I lost it on Gnash too! Good one, Donald Then again, how can you not smile when you see William Hung?! We all need a little Hung to hang on to!
Hi all and Ezio, CSG (Compatible Stereo Groove) was invented in 1967 by HAECO (Holco Audio Engineering Company). This was designed to eliminate the volume difference of folded Stereo recordings and this processing was normally applied at the disc mastering stages. Sometimes it is also on album masters too. Atlantic, WB, and A&M were the primary users of this technology! In short, a way to improve the lot of mono playback/45 RPM releases/ AM Broadcasting. I hope this helps you understand it. It uses phase shifting.
