Tube Amp Archive

Indeed I did

happy to report that I had zero issues running loud for 2 hours straight on the 8 ohm. Something I did must have fixed it!

M Fowler wrote:How about posting that schematic.

Sure thing.

Also, one more possibility: My speaker wire has shrink tubing over the plug. It may have extended a little too far and caused the plug to not make a solid connection if the stars aligned just right. I trimmed it back. I won't be able to plug it in until tonight- so I guess I'll find out if I need to...

Found nothing that seemed strange on the jacks after looking more deeply. Maybe it was a fluke. We'll see how it goes at practice tonight. I only had it happen once and immediately shut down and switched to 16 ohm out to 16 ohm load because the cabinet was new to me and I wasn't sure it was wired co...

Im not seeing anything awkward with the jacks. The ground or ring side is operating normally. Im going to check the tip side in a minute... was a little harder to get to. I did go ahead and adjust the bias on both sets of output tubes... they had drifted a bit... like 5 to 7 mv. I have them both wit...

Looks like they are soldered to a pcb based on this picture I found of this amp with the chassis open, haven't cracked it open yet. I'll hit solder joints.

Get the bias voltage straightened out? Original tubes, no adjustments have been made.

Thats correct. The amp actually has 3 outputs: 16, 8 or 4.

Looks like they are switching jacks. Detail of the output jacks from the schematic attached.

I've been using my head with the 16 ohm tap as long as I've had it, with no issues. I just bought a 4x10 cab that has a 16 ohm input and an 8 ohm input. The amp works fine with the 16 ohm, but cuts out very soon after starting to strum my guitar when I connect the 8 ohm output tap to the 8 ohm input...