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just strum
June 17th, 2008, 06:27 PM
I really don't know how long it's been doing it, but I noticed last night while playing that when I strike the E and/or A I get a distorted sound, If I fret the E at the first fret (F) it still makes this sound, almost like a cracked or torn cone.

I removed the grill (AD30VT) and inspected the speaker and it appears that it has no tears. Is there other parts of the speaker that would cause this?

I am thinking of changing the speaker if necessary. I've never done that, but it would seem to be an easy thing to do.

This will open the door to opinion, but any suggestions on what speaker to get and a good place to buy a speaker.

I know the site is loaded with recommendations, but I don't want to read through a lot of jargon that means little to me. Just provide me with some straight talk.

Ch0jin
June 17th, 2008, 06:36 PM
Sorry if this is too basic a reply, but have you checked all the pots by giving all your controls a quick spin? I almost tore an old harp amp apart because I thought I'd blown it up (sounded exactly like a fried speaker coil) until I noticed a small FX loop control on the back and when I gave it a twist, Bingo! So a speaker replacement became a bit of contact cleaner into he pot and good to go!

just strum
June 17th, 2008, 06:40 PM
Sorry if this is too basic a reply, but have you checked all the pots by giving all your controls a quick spin? I almost tore an old harp amp apart because I thought I'd blown it up (sounded exactly like a fried speaker coil) until I noticed a small FX loop control on the back and when I gave it a twist, Bingo! So a speaker replacement became a bit of contact cleaner into he pot and good to go!

Would that cause it to do that only on E and A?

Oh, I should note to those reading this - I adjusted everything to make it as clean as possible and took out all effects, bass, and treble.

warren0728
June 17th, 2008, 07:01 PM
i've noticed the same thing on my ad30vt....it is a horrible sound and i never found the problem....i too thought it might be grill related. If i remember correctly (i haven't played the vox in a long time) it was worse on some amp models than on others....sorry no help here but i'm interested in an answer too (although i'm think my answer is to sell the amph!)....i like the sound i get from my rp250 into my unmodded valve jr and my peavy classic 20 better than the vox....

ww

just strum
June 17th, 2008, 07:06 PM
i've noticed the same thing on my ad30vt....it is a horrible sound and i never found the problem....i too thought it might be grill related. If i remember correctly (i haven't played the vox in a long time) it was worse on some amp models than on others....sorry no help here but i'm interested in an answer too (although i'm think my answer is to sell the amph!)....i like the sound i get from my rp250 into my unmodded valve jr and my peavy classic 20 better than the vox....

ww

I like the AD30VT, but I will admit I would prefer to be running my RP through a different amp. I guitar binge prohibits getting an amp at the moment, plus I would have to go through the "which amp do I buy" and I just don't need that at the moment.

warren0728
June 17th, 2008, 07:09 PM
I like the AD30VT, but I will admit I would prefer to be running my RP through a different amp. I guitar binge prohibits getting an amp at the moment, plus I would have to go through the "which amp do I buy" and I just don't need that at the moment.
the rp sounded surprisingly good through my valve jr. and it is the noisy model 1....i want to try and mod it one day....the newer ones are much better and you could buy one for what you could sell your vox for (and then you have a real tube amp when you don't use the rp)....i'm just sayin' :whatever: :AOK: :beer:

ww

duhvoodooman
June 17th, 2008, 07:10 PM
I'd definitely check the amp out thoroughly to make sure it's a speaker problem, but if it is, I'd recommend looking at the 10" Veteran (http://warehousespeakers.com/products.php?cat=8&PHPSESSID=18c5bfadcbaf0e67f40b529be5a3de39) from WGS. It's only rated at 20W, but as long as you don't push your AD30VT very hard, that really shouldn't be a problem. If you're concerned about that, you could go with the G10 Vintage (http://www.svvintageamps.com/catalog/product_info.php?cPath=25&products_id=191&osCsid=63e8aeaa435190e0bb86216275d87277) from Celestion....but it will set you back about $80. I have one in my AD30VT and like it very much. The 10" Eminence speakers (http://www.eminence.com/guitar.asp?speaker_size=10) are worth a look, too.

TS808
June 17th, 2008, 07:25 PM
How old is the amp? I've had bad tubes before that have caused that distorted sound on low notes too. I'd not only check the speaker, but the tube too.

Before buying a speaker, I'd check out www.valvetronix.net. Also, one thought would be if you could run the amp through another cab, that would rule out whether or not it's the speaker. Is there a line out that you could test it on another speaker cab or even through an amp's line in? That would tell you if it's the speaker or not.

duhvoodooman
June 17th, 2008, 08:05 PM
Also, one thought would be if you could run the amp through another cab, that would rule out whether or not it's the speaker. Is there a line out that you could test it on another speaker cab or even through an amp's line in? That would tell you if it's the speaker or not.
That's a very good idea. Though it has no speaker jack, the AD30VT does have a line out jack. It's before the power amp, so it won't drive a speaker, but you can plug a set of headphones into it. I do that on mine all the time....

M29
June 17th, 2008, 08:37 PM
I had a similar problem and I would have never thought that is was a partially burnt inline speaker fuse. I know not many amps have speaker fuses but I had a similar situation with a overload protection cutout that heated up and partially cut out causing a resistance. I would check that out unless it does not have either of these. What happened to my amp was the fuse had burnt partially under the chrome end cap and you could not see it. This caused a resistance and the heavier frequencies, (possibly your E and A) were having trouble getting through and were distorted. The higher frequencies were all fine. I replaced the fuse and it was fixed. It was weird because when I first checked the fuse I thought it was good but could not see under the end cap. Just a thought.
It could be the same type problem but in a different area like maybe a loose speaker push on terminal or a bad solder joint. Maybe look for areas that are moved every now and then that could cause a bad connection over time. It may be a partially burnt voice coil too, inside the speaker causing a resistance.
It could be the 12AX7 tube connections too, remove that and wiggle it around in the socket to freshen up it's connections.
Wasn't there a problem with the input jack on the AD/VT series that might be something to look into too. If I remember correctly it was a bad connection that could cause a resistance and show up in the lower frequencies at the speaker end. Shoot maybe it is a bad input cord. You could hear that at the speaker too.

Sorry for the rambling:thwap:
M29

just strum
June 17th, 2008, 08:48 PM
Another thing it might have been caused by - the room next to the music room (for lack of a better term) is the bathroom. Every time someone turns the exhaust fan off, I get a pop through the speaker, could that cause damage that would result in the sound I am hearing?

duhvoodooman
June 17th, 2008, 08:54 PM
Every time someone turns the exhaust fan off, I get a pop through the speaker, could that cause damage that would result in the sound I am hearing?
It would have to be a VERY sharp pop! Extremely doubtful....

Kazz
June 18th, 2008, 04:48 AM
oh boy...if either of you decide to sell that AD30 for a reasonable price....let me know....

tot_Ou_tard
June 18th, 2008, 05:06 AM
Wasn't there a problem with the input jack on the AD/VT series that might be something to look into too. If I remember correctly it was a bad connection that could cause a resistance and show up in the lower frequencies at the speaker end. I don't know about the lower frequencies, but Voxman on valvetronix.net always suggested spraying a little contact cleaner into the input jack. It seemed to fix some problems.

As TS808 says I'd go to valvetronix.net and ask there.

Did you try resetting the AD30VT?

I assume that you have the problem on all amp models & at all master & gain settings.

I have the Celestion G10 Vintage in mine. If it turns out to be a speaker problem I'll give you the stock one that came with my AD30VT.

wingsdad
June 18th, 2008, 07:55 AM
Another thing it might have been caused by - the room next to the music room (for lack of a better term) is the bathroom. Every time someone turns the exhaust fan off, I get a pop through the speaker, could that cause damage that would result in the sound I am hearing?
Strum,
I doubt it's the speaker causing the problem. The circuitry isn't performing right.

Between this phenomenon and M29's post describing 'juice'-related issues, it seems to be a problem of that nature.

Is this happening with only 1 guitar?

Did you try plugging in (the amp, or the power strip it's into, if so) to a different wall outlet, one that's definitely on another breaker than that bathroom?

Did you get the amp from Sweetwater? Still under warranty at all? Maybe a call to them for help?