Tube Amp Archive

There are 2 cheap ways to tell if a OT is bad. One way that cost you nothing is to look at the output tubes in a dark room when the amp is cranked up. The inside of the tubes will glow brighter when your playing and the tubes are driving current into the OT. If you can look at this effect in a norm...

A bad OT is what I was fearing but it’s the only variable left besides the filter caps. Is there a reliable way to test ESR without buying a capacitor tester? For the OT I will probably just source one and tag it into the circuit to see what happens. It’s crazy how the simplest of amps seems to be t...

So I have a friends Reeves Custom 100 head which is a clone of the DR103. The issues he was experiencing was an interimittant static sound and output tube failure. I found a bad output tube, blown mains fuse, and some noisy carbon comps in the PI circuit. I replace all that and install/bias a new se...