Help- Studio Preamp suddenly not working... suspicious wire...

[erickompositör72]

I hadn't used the StudPre in a couple of days (IIC+ arrived! 8) ), so I was puzzled when I was plugging it in, and it was needing the master to be pushed past 3-4 on the Mark II power amp, only to hair a faint, fizzy sound.

I opened it up, and here's what I found -

(I think the reverb is messed up, too? It was like this when I received it in the mail a couple of months ago- I never use reverb so I didn't care...)

and this suspicious wire just lying here:

It looks to be disconnected from something. I have no idea how or when it happened, but I guess it could have happened in the last couple of days?

 

[dtrax]

That white wire needs to be connected to the reverb tank. Locate the tab, just below the green wire (in the photo) that has a bit of solder already.

As to the low output/fizzy sound... start with the obvious stuff like swapping tubes (V4 drives the Main outs), trying the FX loop send (also, be sure to check the Line/Low switch). It could be anything, but narrow down the obvious stuff first.

 

[erickompositör72]

That white wire needs to be connected to the reverb tank. Locate the tab, just below the green wire (in the photo) that has a bit of solder already.

As to the low output/fizzy sound... start with the obvious stuff like swapping tubes (V4 drives the Main outs), trying the FX loop send (also, be sure to check the Line/Low switch). It could be anything, but narrow down the obvious stuff first.

Thanks- I switched all the tubes, tried a different amp's loop return for the power section, tried all the outputs- they all behave the same way. I guess I'll just take it to a Mesa service center.