Bought a new amp today

[Nay]

So I went to Guitar Center today for their Black Friday sale and I ended up buying a used peavey classic 30. Its not in mint condition but I got it for pretty cheap and it has some interesting components. The previous owner installed JJ EL84s and a Weber Blue Dog speaker in it. That was pretty much the selling point for me.

Anyways there are a couple things wrong with it. The reverb does not work, and I'm getting a buzzing sound when I turn the amp up to higher volumes. Currently I am more concerned with the buzzing. Has anyone had this problem with any of there amps...any suggestions?

[Duff]

Hold onto the magnet on the back of the speaker; grasp it and turn up the volume and play some note, etc. Does the buzzing stop?

If so then the magnet assembly is coming loose from the speaker cage and this may well be the culprit. They are usually rivited on and the rivets sometimes go bad. I had this with my Peavey Delta Blues, new speaker solved the problem, clear as a bell now.

Other obvious problems could be loose grill or faceplate problems, something resonating at high volume, vibrating.

Other guys here will probably have some other ideas.

Hope this helps.

[ZMAN]

Right of the bat I would return it due to the reverb not working. It could be a sign that the electronics have been damaged. As far as the buzzing it could be the tubes. turn on the amp and get a pencil with a rubber tip. Tap the tubes one by one and if there is a bad tube that has gone harmonic it will buzz, and you will be able to hear it. It sounds like a broken lightbulb filament in a bulb. That means you probably need some expensive tubes as well. Be careful not to touch anything else. Could be hair raising!
All in all you could be out a couple of hundred for repairs to the amp.
If you bought it that way and paid a very very low price you may have to bite the bullet. If not it should go back for repair. A decent speaker could also be a hundred plus.
A good set of tubes for that could be hundreds as well.

[Radioboy950]

I've had a "buzzing" or rattling sound that I could swear was coming from the chassis, the speaker, the cab...ANYTHING but the output tubes.
Turned out to be a tube, FWIW. Hope it turns out to be a simple fix so you can enjoy your gear.

As to the reverb (or any other known issue) I'd go back to the seller for not disclosing any defects.

Were you able to try the amp so you were comfortable walking out the door with it?

[Nay]

Hey guys,
Thanks for all the help. It wasn't the speaker but I do think it is one of the tubes. There is one of the power tubes that rattles a little when I tap it. Is there any way of fixing this without replacing the tube itself. i.e could the tube just be loose, or could it be the brackets holding the tubes? This is my first all tube amp so I'm not too familiar with them.

I was informed that the reverb did not work before I bought the amp, and I did try the amp before I bought it. One of the employees said he thought the reverb would be a cheap fix...not sure how true that is. I decided to buy it because I do have 30 days to return it, it was priced pretty low, and I got 15% off that price. So I did buy it considering the fact that I might return it in a few days after I did some more research to see how bad these problems are.

[ZMAN]

The tube could be pulled and reset. Make sure you put it back correctly and don't force it. They have pins and holes corresponding to the pins in the tube socket. Most output tubes are in the 15 to 20 dollar range so it won't be a big fix. When a tube sounds like it rattles that means usually that the tube is gone. You don't need to replace all of them. I would get a spare El84, and a 12ax7 and keep them on hand. You can use them on other amps, and if this is your first tube amp I am sure it won't be your last. Sorry but for me I could not live without a reverb.

[Nay]

Thanks for the advice ZMAN. I do want the reverb to work, I can tolerate it for a while without the reverb but I would like to fix it. All the other electronics seem to work fine, the reverb is just out. Could this mean the reverb tank is bad?

[ZMAN]

I have heard of situations where the tank was unplugged or even a broken wire. A good amp tech will find it in a minute and let you know. The only problem is that you have to take it in.
Just a quick question. Did you get the footswitch with it. If not it could be that the reverb is not switched on. sometimes you need the switch. I have not owned a peavey but some amps are like this.

[Kazz]

One thing to add here as a former C30 owner....they are notorious for rattling tubes and the open back design is less than great for gigging and hauling the amp to and fro.....Get yourself a tube tamer or similar device to keep the tubes in check. Also check with Bob at Eurotubes for replacement tubes....it was $76.50 + $8.00 shipping to completely retube my C30 with the high gain option to get it as close to Marshall territory as it would go.

Not only that but Bob wrote me a complete explanation with speaker recommendation as well to get where I thought I wanted to go with that amp. His customer service is impeccable.

[Radioboy950]

Also check with Bob at Eurotubes for replacement tubes

Indeed, Bob is one of the best. The JJs he selected for me outlasted all the other 6L6s I used in my particular combo. If you're doing a JJ re-tube, at least contact Bob and let him know of your needs, concerns about the amp, playing styles, etc. He'll tell you what he thinks. Combos beat up tubes, and he'll take that into consideration.

[Nay]

Thanks for the suggestions. I'll have to check out eurotubes sometime sounds like a trustworthy site.

Kazz, I did not get a footswitch with the amp. I have another footswitch that might work though. I'll try it out.

[ZMAN]

You may have to get a peavey switch. I am not familiar with the amp but does it have a switch that controls the reverb on or off. If not it has to be turned on with the foot switch. You may have a working reverb after all.

[sunvalleylaw]

Congrats on the C-30! A lot of amph for not too much dough. You can get that rattle fixed easily as described and can get a "tube tamer" online for like $10 or so. Just google that name and you will find it. I once in a while would get a little rattle, but not since I put on the tube tamer. Hopefully, the reverb is an easy fix. I love mine. Have fun!

[Commodore 64]

Yeah, I think I kinda miss reverb...my Blackheart doesn't have it. I love the fact that there's aftermarket stuff in your Peavey. Can't wait to retrofit my 1 x 12" cab with a Greenback (clone).

[Spudman]

The reverb is probably going to be a a cheap fix. There is an IC chip on the board that can fry. It's a real cheap thing to buy.

BUT BEFORE YOU PULL IT OUT - make sure to note the marking on top of it so that you can orient the replacement the same direction. Otherwise if it's reversed you'll toast it as soon as you turn it on.

You'll have to pull the chassis out of the cabinet to service this item but make sure you touch noting else in the amp other than this one IC chip. There is stored electricity in the caps that can seriously hurt you.

Follow the reverb leads from the tank to the board and that should tell you right where the IC chip is. You'll need tweezers to get to it.


You may have to get a peavey switch. I am not familiar with the amp but does it have a switch that controls the reverb on or off. If not it has to be turned on with the foot switch. You may have a working reverb after all.

The C30 reverb works without the pedal.

[Nay]

I think I'm going to take it in somewhere and have them check it out, let me know whats wrong with the reverb for sure, and then I'll try to fix it myself depending on how much they'll charge to fix it. That is unless there is some easy way to find out whether something is loose, or the IC is burnt out? Also is their an easy way to access the reverb tank without ripping the tolex open? Sorry for all these questions I guess I should've posted this in repairs haha.

[ZMAN]

Thanks Spud. I really should broaden my amp knowledge. Only Fender and Marshall so far. I figure the rest are emulating those two. Oh and maybe the Vox.

[Spudman]

Nay

The IC chip is the same one that goes into a Tubescreamer. Easy to find and cheap. Just get one and swap it out. If you take it in anywhere it's a minimum 1 hour bench fee which is $30 - $60 just for them to tell you that it's broken.

The chip might be a dollar or possibly two.

[oldguy]

And you might want to buy two............... no way to know if the last owner maybe replaced one and put it in backwards, y'know?

[Spudman]

And you might want to buy two............... no way to know if the last owner maybe replaced one and put it in backwards, y'know?


Excellent point.

[Nay]

Nay

The IC chip is the same one that goes into a Tubescreamer. Easy to find and cheap. Just get one and swap it out. If you take it in anywhere it's a minimum 1 hour bench fee which is $30 - $60 just for them to tell you that it's broken.

The chip might be a dollar or possibly two.

very true... I found some new on newark.com for $0.48 a piece. I'll buy a couple that is a good idea. I take it these chips are not soldered to the circuit board, correct? Also would I need a "cradle" for the chip?

[Spudman]

Make sure the chip is a 4558 and you should be good. You could also get a TL072 in your order. Some folks like that sound of it better. Both will work.

If you hit the amp or move it do you hear any reverb 'sproink'?

[Nay]

I'll be sure to check out the tl072 as well. I do not hear anything when i hit or move the amp.

[Kazz]

The chassis on a C30 is pretty easy to remove without messing up the tolex...just be careful there are some serious caps in there :-)

[Nay]

The chassis on a C30 is pretty easy to remove without messing up the tolex...just be careful there are some serious caps in there :-)

If I left the amp unplugged for a while wouldn't the capacitors discharge eventually?

[Spudman]

If I left the amp unplugged for a while wouldn't the capacitors discharge eventually?


Maybe but I don't know. To mess with the reverb you won't be anywhere near the caps.

[Nay]

I switched the i.c tonight and that did not fix my problem :nope

[Spudman]

Are you sure you got it installed in the right orientation? If you had it in backwards and then turn the amph on it's now fried. You'll have to put another chip in 180 degrees different.

You might also get a meter and see if you are getting current on the wire going to the spring unit. If you do then check the lead after it leaves the spring unit to see if you have current. This will allow to isolate whether it's the spring unit, the send from the circuit board or possibly the cables going in and out of the spring unit.

[Nay]

I put the new chip in with the same orientation as the chip that was in previously. The old chip could have been in backwards though. I bought four chips so I guess I can experiment a little. I guess I could use a meter to check the Vcc and ground pins on the chip to see if there is any voltage across it. I'll also try checking for current on the wires.

[oldguy]

I have no experience with these amphs, but if I'm reading this correctly the chip can only go in two ways..........correct? If so, I'd try reversing the chip and see if that works, since they're relatively inexpensive.

[Duff]

I agree with Spud.

Get an electronic tester and test for current at the tank both going in and going out. Not sure what the voltage would be, maybe someone has an idea of what voltage is expected at the tank.

I had a brand new accutronics I think it was, reverb unit installed in my brand new Hot Rod Deluxe, tweed w the Jensen P12N speaker.

Inside the old tank the tech showed me the broken off spring. When I asked if it couldn't have just been soldered back on he said that doesn't work. Personally I don't know why it wouldn't work.

Another big problems with all electronics is corrosion. If the wires are corroded at or in the reverb unit this could cause the problem and maybe some soldering is in order or at least some deoxidizer spray.

I would definitely do what I could by checking for the presence of current at the reverb inputs and outputs. That is something simple.

Seemingly there is a great probability that the chip you replaced is not the culprit. I would not, with my limitted experience, put it in backwards on purpose and I would assume that the guy at the factory knew more about putting it in than me. I would leave putting that in backwards to a certified technician.

The reverb pot could be corroded badly or the connections to it corroded or broken. I would attempt to look at the reverb pot and spray deox into it and examine the connections of it even if it is a direct mount to the printed cuircuit board. The solder trace on the printed circuit board could be cracked, a very almost invisible crack. Examine it closely and if you are careful with a pencil type soldering iron you can possibly repair the crack with a tiny bit of solder but don't burn things. I have done this type of circuit board repair myself.

Whether or not capacitor discharge thru the traces to the chip or thru the reverb pot connections is present I do not know. I'm not exactly sure how you can accidentally discharge those caps and where the risk is isolated to. You could always check for current with the volt meter.

There is still apparently a lot you can do to check out that reverb unit.

Also, have you isolated the buzzing sound.

[Nay]

Sorry it has taken me so long to respond...I have finals this week so I'm doing a lot of studying

Anyways...
Thanks for the responses guys

I have isolated the buzzing sound I'm 99.9% sure that one of the power tubes is not as tight as it should be. So I'm thinking a tube tamer like others have suggested should fix that.

I also realized I have a breadboard so I can test the chip I took out with a multimeter and see if that one was even bad...

I do not think it is the reverb POT because when I turn the reverb up I can hear a buzz get louder but no reverb??? I should have taken a better look when I had everything apart.

Once my finals are over I plan on taking the thing apart again and seeing what I can figure out with my multimeter...

[Duff]

Actually, turning up the reverb knob and hearing a louder buzz could point to a highly corroded reverb pot. Seemingly when you turn the reverb knob up you are getting a result: a louder buzz.

On some of my corroded guitar pots there is just a buzz in the badly corroded spots before I twist them several times or spray in some deox.

I would not rule out the reverb pot myself.

That is a really awesome amp and definitely worth working on to see if you can correct the seemingly small problems. I have a Delta Blues that is very similar and had a buzz that was the rivited speaker magnet being loose. Got a new speaker and the problem is solved. Before solving the buzz I temporarily solved the problem by forcing a thin guitar pick between the magnet and the speaker cage frame. This temp solution worked good.

[Nay]

alright so I pulled out the reverb tank and so far I'm not getting much. I tested the input and outputs of the reverb tank and did not get anything. However I'm not sure I was testing at the right points.

I tested at the ground outside the tank and the hot wire on the inside of the tank. Is this right? I ask because in the manual for my multimeter it says test at the current source and then after the load. Does this mean I should take the chassis out and test at the power switch and on the inside of the reverb tank?

[Nay]

So I'm not getting any current at the input of my reverb tank. The connections all seemed soldered alright. Everything else with the tank looks fine (springs are not broken). Any suggestions?

[Duff]

Cany you follow the wires from the tank back to where ever they come from and check for current there?

Remember, a plugged in amp is very dangerous. Plus, what are you looking for in terms of voltage? Twelve volts? One hundred and ten volts? Some other voltage?

You might be able to trace the problem back, step by step to where the circuit is interupted.

Now might be the time to take it to a qualified amp technician. Usually you will not find one of these at a regular music store. You need to locate an authorized service center that will know all about Peavey amps. The guys near me are not outrageously expensive but it is over sixty miles one way to get to their shop and then you have to drop off the amp and wait a few weeks for them to get to it. They will know what to do and will tell you what the buzz is.

That is a nice amp but it sounds like you will have to put some more money into it to get it right. Looks like it is more than just some tinkering around that you can do.