I just purchased a Peavey cs-400 Amp and when demoed it worked great...That amp has a crowbar board mounted on the speaker out jacks...Of the five different CS400s only the "C" model had the output triac, so that pretty much tell us that you have the "C" version of the original 400...
Does anyone have any information on a Peavey stereo chorus 400 cabinet...I can get the cab for $30 with a speaker not working...A local guy who was Trace Adkins's and Sammy Kershaw's guitar player on their way up has been using his Classic 400 forever...For $30 I wouldn't even hesitate to buy it...
I'm using it as a guitar amp along with a Danelectro distortion pedal and it has a wonderfully warm tone with the Strat...Other than that it's a great amp and louder than hell...It still has the original JBL 15 inch speaker...