Hello players. I have a basically new Fender "63 Tube Reverb Tank (reissue) that I've decided to let go. I changed out the stock tubes. Instead of a 6V6 I found a 6K6GT @ Tube Depot. The 6K6 GT is made by RCA. The 12AX7 & 12AT7 are JJ's. It has no issues. Sounds like it should. Since I got my Custom Vibrolux Reverb modified the reverb is working now. If you ever need a set of fine quality Caps for your Fender Amp or if you have a CVR that needs to be tamed, go to John Fromel Electronics. He makes kits for amps and pedals too. The components that he sends me are the finest available.