Problem with a Vox AD120VT.

[beggar_guitar]

I recently picked this amp up from a friend who owes me some cash. I don't really want the amp so I intend to sell it. Take the cash that is owed to me, and then give the guy the rest of it.

We plugged it in when I went to pick it up, and it worked fine. Sounded Ok, but when I got it home it was making some terrible noises.
Every tone I play is distorted. I've messed with all the settings, but even on a clean setting with little to no gain notes are distorting. I wish I had a better description of the sound. Low notes tend to be the culprit worse than higher ones, but it will clear up for a few minutes (if I am lucky) and everything will sound fine.

Any ideas? Anything more that I would need to describe about the problem so someone here could help me out?

 

[Gearjoneser]

Re: Problem with a Vox AD120VT.

It's probably 1 of 2 things. It's possible that the 12AX7's in it have failed, but also likely that the computer logic got scrambled, and needs to be rebooted.

I think the way to reset the logic on L6 and Vox is to turn the amp off, hold 4 fingers down on the channel buttons, then turn the amp on. It'll probably erase all the presets, but who cares.....it might fix your problem.

 

[beggar_guitar]

Re: Problem with a Vox AD120VT.

It's probably 1 of 2 things. It's possible that the 12AX7's in it have failed, but also likely that the computer logic got scrambled, and needs to be rebooted.

I think the way to reset the logic on L6 and Vox is to turn the amp off, hold 4 fingers down on the channel buttons, then turn the amp on. It'll probably erase all the presets, but who cares.....it might fix your problem.

Thanks. I will give that reboot a try!
If that doesn't work how can I tell for certain whether or not it is the tube? Also how hard is that to change out?

 

[innerdreamrecords.co]

Re: Problem with a Vox AD120VT.

How old is the amp? They're suppose to last about three years Ive read here on these forums.

 

[beggar_guitar]

Re: Problem with a Vox AD120VT.

So I did the reset and the problem still persists, but now I think my buddy blew one of the speakers. I unhooked the left speaker and the amp played just fine but on the right speaker it was still distorting.

I suppose a speaker change is in order before I can sell this thing. Any idea how much they run?

 

[Gr8Scott]

Re: Problem with a Vox AD120VT.

You can probably get Emi Red Fang speakers (definitely the best suited for that amp) for a very low price (considering the quality of the speaker) from Mojo Musical Supply. I'd suggest two of those or maybe a mix between one of those and a vintage 30 clone also made by mojotone called the BV-30V. The BV-30V will cost roughly half what the emi does.

 

[beggar_guitar]

Re: Problem with a Vox AD120VT.

You can probably get Emi Red Fang speakers (definitely the best suited for that amp) for a very low price (considering the quality of the speaker) from Mojo Musical Supply. I'd suggest two of those or maybe a mix between one of those and a vintage 30 clone also made by mojotone called the BV-30V. The BV-30V will cost roughly half what the emi does.

If I were going to keep the amp I may go that route, but I will most likely be selling it.

 

[Gr8Scott]

Re: Problem with a Vox AD120VT.

The BV-30V is cheap man. Very cheap for the quality.

 

[beggar_guitar]

Re: Problem with a Vox AD120VT.

The BV-30V is cheap man. Very cheap for the quality.

Oh Ok. I looked up the Red Fang and missed that one.

How do they sound in comparison to the speakers that come stock w/ the AD120?
Only one speaker sounds bad so I am considering just replacing that one.

 

[Gr8Scott]

Re: Problem with a Vox AD120VT.

The red fang sounds incredible in comparison to the stock speaker. The BV-30V is primarily better on the marshall and dumble models but can get a bit hairy if you aren't careful. Call Mojo and ask what the prices are if you order. Those prices usually improve when you are placing an order.

 

[LoFiBrian]

Re: Problem with a Vox AD120VT.

could be that the 12ax7 running that stereo side to that speaker needs replaced...

 

[Gearjoneser]

Re: Problem with a Vox AD120VT.

Yeah, replace the 12AX7's with fresh ones. After getting the chassis out, you'll see that it's hard to get your fingers around the tubes because they're buried in the amp. I took a flathead screwdriver and carefully pried them free from the side.

If the amp has good tubes and has been rebooted, and there's STILL a problem, only a Vox certified repair station can do anything with it. That's the problem with computerized amps.

 

[beggar_guitar]

Re: Problem with a Vox AD120VT.

So are there two 12ax7's or just one? One for each side?

 

[JumpMarine]

Re: Problem with a Vox AD120VT.

Correct on two 12ax7's. When I had my ad60H the easiest way I found to pull the tubes was to: First remove the rubber grommet, then use packing tape to carefully wrap around the top of the tube leaving a tail of tape sticking out. CAREFULLY and gently wiggle the tube while pulling. The tube will pop right out.