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View Full Version : Marshall Valvestate 65R Repair?



mars2010
September 11th, 2010, 09:55 PM
hello, i've got a used valvestate 65R that only sends signal out of the 'line out'. i'm wondering if anyone has ideas on what kind of fix might be needed. i'm getting ready to change out the 12ax7 tube and hoping for a quick fix, otherwise i'll have to start looking at schematics. thanks for any ideas...

kiteman
September 12th, 2010, 06:56 AM
Do you mean the "send" on the effect loop? That would mean the preamp is working. If the amp's not working, ie no sound then it might be the speaker or the power amp.

deeaa
September 12th, 2010, 07:21 AM
Yep indeed; fried the actual amp circuits, or the speaker, or - most likely - a capacitor has gone dry/blown. The preamp is fine if the line out works OK.

See if there are caps that are obviously bad, and test the speaker, for instance put leads on a used 9V battery and touch the + and - on the speaker with the leads from a battery - if you can make it sound a 'snap' it's not fried, if it doesn't respond at all the coil is fried/shorted and that'd also short and quickly fry the amp's power section.

I once blew one of these, or a very similar one, by accidentally letting the speaker minus cord touch the chassis of the amp - died instantly, burned the amp power trannies.

Commodore 64
September 13th, 2010, 02:03 PM
Check the input jacks. They are probably PCB mounted, and can come loose. I just ordered 4 new jacks for my Peavey Bandit. I hope they arrive today!

Duffy
September 13th, 2010, 04:54 PM
Mars2010,

What did you find so far?

I would say check it as far as you can. Check the speaker with a battery or something. Examine everything else for obvious burned spots on the pcb board, etc.

Might be inexpensive to get fixed.

Those Valvestates ised tp be cool amps. I have a VS30R, no tube, I like a lot and want to put a new speaker in. It sounds a little muddy at present.

Then again, for the cost of fixing it you could probably buy a new style Marshall MG series amp; like an MG 30, which is proably a really decent amp of its type but for a little more you can get a Bugera V22 or other all tube amp, for less used, if you look around. I would imagine there are a few used V22 Bugeras out there.

It would be great to save the VS65R if you can, considering that it is in great shape otherwise.

Let us know what you find.

FrankenFretter
September 13th, 2010, 08:10 PM
I have a VS100. The previous owner had some work done on it by a friend of mine. I believe that there were problems with some of the circuit board traces, but I couldn't swear to it. I bought it for a great price after the repair, and I haven't really had any problems with it. I don't know about yours, but mine sounds great, that real Marshall growl. Good luck with yours!