Splawn Competition problems. Enzo. You know about these?

[Redline]

I purchased a non working Splawn Competition off ebay. The half power switch literally exploded. I replaced that switch and she atleast makes sound. Problem is I don't think it sounds like it should. When I take the amp off standby it make a loud hissing sound but goes away after about 10 seconds and then it's pretty quiet. It doesn't have much gain at all. It's supposed to be a hot rodded Marshall but with the gain maxed and gear switch in 3rd gear it doesn't even have as much gain as my old JCM800. The gear switch doesn't seem to do anything to the gain/voicing. The mids sound like a cocked wah. Before you say just send it to Slawn just let me tell you that I am a hard headed DIY guy so shipping it to Slawn isn't going to happen. I'll keep trying till I get it. I almost forgot to mention that the volume seems to be fine and all tubes have been changed. thanks

[Enzo]

I have never seen one. One reason someone might tell you to send it to Splawn is that it comes with a lifetime warranty.

As to anything inside the amp, without a schematic it would be just guessing.

[Mick Bailey]

Its warranty is limited to the original purchaser, which makes me think the guy selling it wasn't the original owner either.

The first thing I do with an unfamiliar amp is to make sure I'm operating it correctly, and that I understand how it works. Seems obvious, but sometimes there are gotchas - like the FX loop level if it's got an active loop which stays active with nothing plugged in (like Two Rock and some VHT). So first think I do is get a user manual to make sure. Small builders can sometimes use quirky approaches to differentiate themselves in a crowded and competitive market.

If the volume is fine, do all the other controls have an effect on the sound? Is the gear switch actually working - if it's a relay switched amp are the relays operating?

I don't know the amp, but there are general things you can check. DC values on the supply nodes would be my first consideration, and any low-voltage DC supplies for semiconductor or relay circuits. If the DC levels are fine at the supply, check the DC values on the tube socket pins. If the DC is off, no amount of signal troubleshooting will help.

It's worthwhile asking for a schematic, 50-50 chance you'll get one.

[Redline]

I go her running good last night. It was just a few burnt solder joints at 2 resistors. I replaced those resistors also. I stayed up until 2am playing it last night.

[Chuck H]

You may want to trouble Splawn for a schematic, or at least some critical voltages if they won't share. I find that most of the time when an amp fails in the form of burned traces and resistors, just repairing the traces and replacing the resistors doesn't actually fix the amp. SOMETHING caused the failure in the first place and may still be a problem.

[tedmich]

+1 with what Chuck said, I find its usually bad tubes that snowball downhill...