xtian

You are correct. Jacks are wired in parallel, as you said. Two 8-ohm speakers wired in parallel present a 4-ohm load to the amp.

Do you have a signal generator and scope?

A typical tube guitar amp has the cathode of the first triode at about 1.5 volts above ground which means that the largest input signal...

20 watts is a bit shy to compete with bass and drums. But first confirm if the amp is healthy: measure the amp's RMS output to see if...

At "bedroom levels," you should be fine with a 25w speaker. Example...

The manual probably meant Shuguang 12AX7s, but Shuguang hasn't produced tubes for a few years. You're probably fine to use any 12AX7...

I tightened everything and still humming, did not try loosening! Actually the whole amp vibrates with it which is interesting, it must...

They are the most time consuming and expensive amps to maintain...they also have a variety of bugs and issues.... To change 1 relay is a...

I've serviced some modern Orange amps, using KT88s or 6550s. The plate voltages are super high, but the screen voltage are half that, so...

The best test is in the amp itself. Tube testers miss about 60% of all potential problems. Tube labs test everything that a normal tube...

That YIHUA looks fine, and nearly identical to the one I got from Circuit Specialists. 75 watts, and easily replaceable tips, handle...

I got my latest amp build up and running (first amp build in @3 years) a) I used an MPS PT285-2 (a prototype PT he hand wound years...

Pot tracks could simply be dirty and intermittent. Deoxit.

Years ago I built two lower wattage versions of a Marshall 2204 a) A 20 watt head w/6V6 x 2 -- Fixed bias b) A 14 watt head w/EL84 x...

Buy a 50 watt amp! You will need a pt, and a ot, plus a redesign of the power supply.