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kid_amnesiac
September 12th, 2008, 03:31 PM
New to the forum, and I hope someone might be able to point me in the right direction. My amp (vox ad50vt 2x12) has started to malfunction in two ways (not sure if they are related):

1.) Amp doesn't respond when I play my guitar unless I really lay into it with the volume fairly high.

2.) The volume cuts in and out and the signal output decays much faster than it used to.

I was thinking it might be a loose connection somewhere in the amp, but I wanted to ask around before I started opening things I shouldn't be opening.

Thanks for the help.

-Vito

tunghaichuan
September 12th, 2008, 03:47 PM
It could be a lot of things. In my experience it sounds like a bad solder joint or like you said, a loose connection. I would suggest that you take it to a tech, your local music store may have one or be able to refer you to one.

Opening up the amp and poking around inside it is a bad idea. Even thought it is solid state and has relatively low voltages in most of the amp, you can still shock the crap out of yourself if you don't know your way around the inside of the amp. You also may unknowingly break something else in the amp which will cost more to have fixed.

A good tech will have diagnostic tools and should be able to isolate the problem and fix it.

My $.02

tung



New to the forum, and I hope someone might be able to point me in the right direction. My amp (vox ad50vt 2x12) has started to malfunction in two ways (not sure if they are related):

1.) Amp doesn't respond when I play my guitar unless I really lay into it with the volume fairly high.

2.) The volume cuts in and out and the signal output decays much faster than it used to.

I was thinking it might be a loose connection somewhere in the amp, but I wanted to ask around before I started opening things I shouldn't be opening.

Thanks for the help.

-Vito

warren0728
September 12th, 2008, 03:57 PM
isn't there someway to reset the ad**vt amps...that might help....i don't have my manual nearby so i'm not sure how to go about it....

ww

kid_amnesiac
September 12th, 2008, 04:01 PM
isn't there someway to reset the ad**vt amps...that might help....i don't have my manual nearby so i'm not sure how to go about it....

ww

I followed the reset procedure, but that didn't accomplish anything.

BluezOldy
September 12th, 2008, 04:13 PM
You might an answer to your question at the Valvetronix forum:

http://www.valvetronix.net/forums/

marnold
September 12th, 2008, 07:22 PM
This may be a really stupid question, but did you try it with a different cord and/or a different guitar? Could be a short in the cord or an input jack gone wonky too.

M29
September 12th, 2008, 08:21 PM
If I remember correctly there were problems with the input jacks. I think they were falling into the amp and there could also be a bad connection with the jack. It sounds like a bad connection with the jack to me. IMHO:D

M29

TS808
September 12th, 2008, 08:22 PM
New to the forum, and I hope someone might be able to point me in the right direction. My amp (vox ad50vt 2x12) has started to malfunction in two ways (not sure if they are related):

1.) Amp doesn't respond when I play my guitar unless I really lay into it with the volume fairly high.

2.) The volume cuts in and out and the signal output decays much faster than it used to.

I was thinking it might be a loose connection somewhere in the amp, but I wanted to ask around before I started opening things I shouldn't be opening.

Thanks for the help.

-Vito
Wonder if the tube is going on it?

M29
September 12th, 2008, 08:40 PM
If you are inside the amp it wouldn't hurt to wiggle the tube around in the socket a bit in case there is a bad or loose connection there.

M29

marnold
September 13th, 2008, 04:51 PM
Oh! I just remembered something else. One problem that often came up with the Vox Valvetronix amphs is that the line out jack would get corroded and cause periodic cut-outs. Spritzing some contact cleaner on a guitar cable connector and pushing it in a couple of times would take care of the problem. If you use the line out a bunch, that might be it. It's something cheap and easy to check anyway.

kid_amnesiac
September 13th, 2008, 06:26 PM
I've tried the cleaner trick in the input jack, but that didn't do the trick. Interestingly, moving the amp from one room to another allowed the amp to work again.

I'm pretty sure that points to a faulty connection somewhere in the amp. Would it be extremely dangerous to open the amp and check connections?

BTW, I've tried a combination of chords and guitars, so im pretty sure it isn't anything on that end.

Again, thanks for the help

marnold
September 13th, 2008, 06:31 PM
Did it work when you moved it back again? If not, it's entirely possible that something is flaky with your outlet. Personally, I wouldn't mess with the guts, especially since you really don't know what you are looking for.