Members gsHarmony Posted August 23, 2005 Members Share Posted August 23, 2005 I just had 2 preamps die last week, now my guitar amp is acting quite strange. There is occasionally loud static when I play it. I initially thought it was the tubes, but I just replaced them several weeks ago. Also, I have tried different cables and different guitars and had the same problem so it is definitely the amp. Here is a clip: http://www.cs.ucr.edu/~gstitt/ampproblem.mp3 The static is very apparent in the beginning, then goes away, them comes back. Does anyone have any idea what the problem might be? If not, then this is going to be one expensive month. By the way, the amp is a Peavey Duel 212. Link to comment Share on other sites More sharing options...
Members seaneldon Posted August 23, 2005 Members Share Posted August 23, 2005 personally, i'd say that the problem lies in the last sentence you wrote. Link to comment Share on other sites More sharing options...
Members gsHarmony Posted August 23, 2005 Author Members Share Posted August 23, 2005 personally, i'd say that the problem lies in the last sentence you wrote. lol, I wish it was that simple. Suprisingly, a lot of people actually like this amp. Link to comment Share on other sites More sharing options...
Members where02190 Posted August 23, 2005 Members Share Posted August 23, 2005 Three pieces of electronics failing within a few weeks is a pretty far fetched conincidence, I'd be checking the voltage and ground of the AC service. Link to comment Share on other sites More sharing options...
Members numrologst Posted August 23, 2005 Members Share Posted August 23, 2005 go get something to test your ground at home. I have a surge protector that does this for me. Link to comment Share on other sites More sharing options...
Members gsHarmony Posted August 23, 2005 Author Members Share Posted August 23, 2005 My power outlets don't have a ground (its an older house), but I've never had a problem like this before. Link to comment Share on other sites More sharing options...
Members numrologst Posted August 23, 2005 Members Share Posted August 23, 2005 That could be the problem if you are plugging in electronics that are supposed to be grounded. But it is hard to do that. The units that burned out and your amp, do they have a ground prong? Link to comment Share on other sites More sharing options...
Members bjorked Posted August 23, 2005 Members Share Posted August 23, 2005 Originally posted by gsHarmony My power outlets don't have a ground (its an older house) Maybe you should consider moving... In all seriousness I would never plug a piece of equipment into an ungrounded AC. Maybe there's a cheap way of grounding your power, unfortunately I don't know of one. Link to comment Share on other sites More sharing options...
Members gsHarmony Posted August 23, 2005 Author Members Share Posted August 23, 2005 The preamp does not have a ground prong but the guitar amp does. They are both plugged into surge protectors that are plugged into the groundless power outlet using an adapter (which is not grounded). I realize this isn't ideal and that the surge protector doesn't work as well without ground, but I have been doing it this way for over 10 years and never had a problem. I looked into grounding all the outlets about a year ago and it would have been a major pain in the ass. Link to comment Share on other sites More sharing options...
Phil O'Keefe Posted August 23, 2005 Share Posted August 23, 2005 A PITA beats the heck out of a burnt down house - or being dead. I'm serious here. IMO, the best thing you can do is to get an electrician out there ASAP. And quit using 3/2 adapter plugs without running them to ground! As far as the amp goes, let's start by doing some classic troubleshooting. You can start at one end of the signal chain and work your way to the other end of the chain, and replace things, one at a time, until you isolate / locate the source of the problem. IOW, have you tried a different guitar? Okay, if the noise is still there, a different cable(s)? Using any stompboxes? Pull them out of the chain one at a time and test the sound again. Have you tried using a different amp, but leaving everything else unchanged? If exchanging one thing out gets rid of the problem, but then the problem comes back when you reinsert that item into the chain, then you've found the source of your problem. Back to the AC issue. Have you tried the rig at another location (not that same house!) and seen if it still has the same issues? Going back even earlier in the chain, is it possible you have a dirty or loose output jack on your guitar, or for that matter, on the amp input? Checked your speaker connector / output jack lately? Link to comment Share on other sites More sharing options...
Members gsHarmony Posted August 23, 2005 Author Members Share Posted August 23, 2005 As far as the amp goes, let's start by doing some classic troubleshooting. You can start at one end of the signal chain and work your way to the other end of the chain, and replace things, one at a time, until you isolate / locate the source of the problem. IOW, have you tried a different guitar? Okay, if the noise is still there, a different cable(s)? Using any stompboxes? Pull them out of the chain one at a time and test the sound again. Have you tried using a different amp, but leaving everything else unchanged? If exchanging one thing out gets rid of the problem, but then the problem comes back when you reinsert that item into the chain, then you've found the source of your problem.Back to the AC issue. Have you tried the rig at another location (not that same house!) and seen if it still has the same issues? Going back even earlier in the chain, is it possible you have a dirty or loose output jack on your guitar, or for that matter, on the amp input? Checked your speaker connector / output jack lately? I checked all these things and they didn't solve the problem. The only thing I haven't tried is a different location that actually has ground. I'll let you know the results. Regarding the 3/2 adapters, what should I run the ground to? Wouldn't this be just as much of a pain as replacing the outlets? Link to comment Share on other sites More sharing options...
Members doug osborne Posted August 23, 2005 Members Share Posted August 23, 2005 Originally posted by gsHarmony ... what should I run the ground to? Wouldn't this be just as much of a pain as replacing the outlets? A true earth: a water pipe (if your whole house is piped with copper, hopefully), or a ground rod. Sometimes your cable TV, if you have it, is grounded to earth. Link to comment Share on other sites More sharing options...
Phil O'Keefe Posted August 23, 2005 Share Posted August 23, 2005 I checked all these things and they didn't solve the problem. So for clarification here, let me ask this - with a completely different rig, you're getting the exact same problem? IOW, a different guitar / cables / amp gives you the same noise? If that's the case, then I'd definitely suspect faulty AC service in your house. The only thing I haven't tried is a different location that actually has ground. I'll let you know the results. Please do! Link to comment Share on other sites More sharing options...
Members gsHarmony Posted August 23, 2005 Author Members Share Posted August 23, 2005 So for clarification here, let me ask this - with a completely different rig, you're getting the exact same problem? IOW, a different guitar / cables / amp gives you the same noise? If that's the case, then I'd definitely suspect faulty AC service in your house. Sorry for not being specific. I tried everything except a different amp. If a different amp does the same thing, there is definitely something wrong with the AC. I did notice that one of the power tubes in the amp was very loose. I talked to the guy from Eurotubes and he suggested that I should fix the pin holders in the socket of the loose tube. Link to comment Share on other sites More sharing options...
Members Paully Posted August 24, 2005 Members Share Posted August 24, 2005 Originally posted by gsHarmony Sorry for not being specific. I tried everything except a different amp. If a different amp does the same thing, there is definitely something wrong with the AC... Not really! Have you tried the equipment at a different house location; one with a 3-pin grounded system? That should answer the question of your house supply. Paul Sorry gs.. I missed where you suggested this above. Link to comment Share on other sites More sharing options...
Phil O'Keefe Posted August 24, 2005 Share Posted August 24, 2005 I did notice that one of the power tubes in the amp was very loose. I talked to the guy from Eurotubes and he suggested that I should fix the pin holders in the socket of the loose tube. That could DEFINITELY be an issue! Especially since the problem seems to be worse when you really "dig in" on some notes. Also, the fact that you had a couple of preamp tubes die recently makes me a bit suspicious. Yes, you replaced the tubes, but maybe the new tubes are not making contact in their sockets as securely as they should... also, when the preamp tubes fried, did they arc? Any traces on the tube sockets? And are they ceramic sockets or not? I'd take the amp to a different location / place first and see if the problem continues. I'd also try a different amp at your place (if you can borrow another amp or have two) and see if the problem is still there with a different amp. Same problem, different amp = bad AC. No problem with current amp at different location (with a known good AC supply and proper grounding) and it's the AC at your place. Same problem with your amp at the new location, and it's almost certainly in the amp. Start with the tubes and sockets... if that doesn't do it, it's time for a service call for the amp. One VERY SERIOUS WARNING: If you are not familiar with safety concerning high voltage equipment, if you have any doubts about your ability to do ANYTHING inside that amp, get someone who knows what they're doing to help you, or take it to a qualified tech. EVEN IF IT'S UNPLUGGED, the filter caps in your amp can store enough of a charge to give you a serious shock long after you last had it plugged in. Be safe, and be careful! Link to comment Share on other sites More sharing options...
Members Richard Guy Posted August 24, 2005 Members Share Posted August 24, 2005 One can get a serious jolt re-tensioning the tube pins/sockets if the caps have not discharged. Also remember to unplug the amp. You might want to unplug the amp and leave the stand-by switch to 'on'. That will bleed most of the stored voltage. Phil has revealed some serious things to ponder. You might want to try running seperate, proper, AC service to the room where you play your guitar. Link to comment Share on other sites More sharing options...
Members gsHarmony Posted August 24, 2005 Author Members Share Posted August 24, 2005 Should I wait a certain amount of time after unplugging the amp before working on it? Also, I plan on at least fixing the main outlet that I have most of my equipment plugged into. I previously planned to have all the outlets fixed, but it wasn't cheap and I will probably only live here for another 6 months, so I just decided to wait until I move. Link to comment Share on other sites More sharing options...
Members Paully Posted August 24, 2005 Members Share Posted August 24, 2005 Originally posted by gsHarmony Also, I plan on at least fixing the main outlet that I have most of my equipment plugged into... Unless you are familiar with high power AC, do NOT attempt the following suggestion by yourself. Have a qualified electrician perform the procedure!. 1) Locate the fuse at the AC box that feeds that outlet. Shut it off. Use a test light or something that will confirm that the outlet is dead. 2) Remove the front cover plate, unscrew the outlet and pull it out of the box. 3) If the wires coming into the box are surrounded by metal casing(BX), AND that casing is firmly clamped to a METAL box, then you can probably replace the 2 prong outlet with a 3 prong with no modifications. Reconnect the black and white wires exactly as they were wired to the 2 pin. If connected properly, the white wire should connect to the larger slotted outlet port, and the black to the smaller slotted port. 4) Upon refastening the new outlet, the ground pin will touch the frame of the metal box, which is grounded thru the BX cable to the fuse box(check continuity there). That will be all you need. You can then turn the breaker back on. If the fuse blows, you have the wires reversed. I re-did a whole house that way, and it works fine. Again, if you don't feel qualified, call an electrician. Good luck, Paul Link to comment Share on other sites More sharing options...
Members gsHarmony Posted August 24, 2005 Author Members Share Posted August 24, 2005 I definitely wasn't planning on updating the outlet myself. Link to comment Share on other sites More sharing options...
Phil O'Keefe Posted August 24, 2005 Share Posted August 24, 2005 Originally posted by gsHarmony Should I wait a certain amount of time after unplugging the amp before working on it? You can wait for a few days, which may or may not do the trick, or you can learn how to discharge the filter caps and how to use a VOM to check for dangerous voltages... As Rich said, leaving the amp's "standby" switch "on", with the amp unplugged for a day or two will usually do the trick. However, as a matter of habit, whenever I'm working on a tube amp (unless I have to have it "live" to test something, in which case, I keep one hand in my back pocket ), I make sure the amp is unplugged and for my very next step, I discharge the filter caps manually. I then check with the meter and then get to whatever I was planning on doing. Obsessive? Maybe... but IMO, getting into that habit and doing it EVERY TIME is a very smart and safe way to work. Trust me... 1) Locate the fuse at the AC box that feeds that outlet. Shut it off. Use a test light or something that will confirm that the outlet is dead. Once upon a time (around 1993), dumb-dumb here (that would be me) was fixing some electrical stuff on top of an unenclosed balcony / loft. Dumb-dumb (yes, for those of you who missed it the first time, that would be me), apparently switched the correct breaker off. But dumb-dumb (yes me, remember?) either didn't bother testing with a meter to see if the circuit was really dead, or accidentally touched the wrong thing while attempting to do so. Dum-dumb (YES! I'M an IDIOT! ARE YOU HAPPY NOW? ) says "apparently" because he has no recollection of what happend at any time that day until several hours later, when he awoke (after having fallen about 14') in a pool of his own vomit (apparently I had regained consciousness breifly earlier and tossed my cookies due to the concussion and intercranial swelling / bleeding I suffered, but I sure don't remember that), and spent the next few days in a hospital, not knowing who I was or what the hell hit me. And a considerable amount of time and effort over the following years trying to relearn things I had previously known. Obsessive about safety now? Damn straight I am. And the sad thing is, I apparently was pretty good about it before my accident. Just not good enough to prevent me from being a dumb-dumb. We don't need any more dumb-dumbs around here - one is more than enough. So please be careful folks. PS And yes, that's an actual, true story. I DID get zapped (one hand in the back pocket probably saved my life) and I did take quite a header. All because I was a dumb-dumb and not careful enough. Link to comment Share on other sites More sharing options...
Members gsHarmony Posted August 26, 2005 Author Members Share Posted August 26, 2005 Wow, that is a crazy story. Definitely makes me think twice before doing any electrical work. I tried out the amp on a grounded AC outlet and it had the same problem. I then fixed the loose tube by retentioning the tube sockets, after determining it was safe to do so. The amp seems to be fine now. I actually managed to solve the problem without bodily harm. I am having an electrician come out next week to redo all the AC outlets even though I will only be here for a few more months. I am getting over the cost by convincing myself that with my luck, all my equipment would have broken before I moved. Thanks for everyone's help. Link to comment Share on other sites More sharing options...
Members gsHarmony Posted September 1, 2005 Author Members Share Posted September 1, 2005 Well, I had all the outlets replaced so they are now grounded. It actually wasn't as much of a pain as I thought. The hardest part was moving all the damn 300 pound furniture away from the outlets. So now the outlets work fine, but my back no longer does. Link to comment Share on other sites More sharing options...
Members Richard Guy Posted September 1, 2005 Members Share Posted September 1, 2005 Great ! Just don't 'strap-on' a Les Paul until your back heals Link to comment Share on other sites More sharing options...
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