Building the YC156 amp helped to reduce the size of my junk box, but I still have a lot of parts to "get rid of". It's usually against my principles to use multiple small devices when one larger tube can do the job better, but I had enough of the small 3CPX800 tubes on hand so I decided to make another amp using a pair of them. Like the YC156 amp, this amp has some serious limitations: manual tuning, loud blower-must be remote controlled, big/heavy, etc. But it also has some useful features: vacuum relay QSK, hot-switching protection, and faster warmup (3 minutes instead of 7, but still annoying).


Design notes




Test data and results