Poorly amp. Help please. Suhr Badger 30 (EL34)

fretmeister

I'm getting volume drops and crackles when I play. It's all fine, then suddenly it drops and crackles, then is fine again.

 I have already swapped the power tubes, but I don't have any pre amp tubes to swap (on the way) 

When I swapped the power tubes it stopped for a bit, but that could be just the intermittent nature of the issue.

 There is no crackle when I'm not playing, or at least none I can hear.

 I might be imagining it, but it seems to smell hotter when it does it. 

Any ideas? Will fresh preamp tubes sort it or am I looking at an expensive trip to a tech?

ICBM

Try swapping the preamp valves around, if you don't have spares. If the problem stops or changes drastically, you know it's a preamp valve. If it stays exactly the same then it isn't.

Since that amp appears to be cathode-biased, it could also be a failing cathode cap or resistor - that might cause a crackle only when under more voltage than at idle, and it might smell hot as well.

fretmeister

I shall try the preamp swap tomorrow, thank you.

If it's a capacitor or resistor change - any ideas what a tech might charge to fix it?

(It is cathode biased)

Ta

viz

Does it have reverb powered by one of the preamp valves? First turn the reverb off (or take the reverb valve out) and see if the problem still happens. If it does, it's likely that the reverb valve is ok. So take that one and swap it periodically with each of the others with the reverb off; and see which one was the faulty one.

ICBM

If it's straightforward and easy to diagnose, under £50 all in I would hope. Possibly quite a lot under depending on how quick/reasonable they are.

It could also be a screen resistor - either could have been caused by a previous valve failure - but I think that's less likely to smell hot.

fretmeister

Thanks chaps.

No reverb! Good old fashioned simple 1 channel amp that sounds awesome. When it's not crackling!

fretmeister

Mmmm

Just tried some different pedals that I powered with a One Spot and not my PP2 and I couldn't recreate the problem.

Then the previous pedals and a One Spot.

Now I'm wondering if it's my PP2 that's buggered.

Catthan

Any updates?

fretmeister

Not as yet!

Been working a bit today so I haven't had a chance to fully crank it up for a long enough time to rule out either the PP2 or the amp.

It's still entirely within the realms of possibility that I'm doing something stupid!

Catthan

I see. I guess trying it straight in without fx for some time would show whether it's the amp or not. 

Do you have an other amp to run the PP2 board and see if it does it?

Pls keep me posted and fingers crossed..

Cacofonix

Desoldering itself?

fretmeister

Finally got a chance to run it for about 3 hours. used a different power supply with the pedals

Either the problem is very intermittent indeed, or it's the Pedal Power 2.

The amp was sounding spectacular! Just had some verb in the loop for the most of it. Glorious sounding thing!

ThePrettyDamned

Have you got another amp?  Try the pedal power with a different amp maybe.