Members avirox Posted October 18, 2009 Members Share Posted October 18, 2009 Hi guys, I recently picked up a Peavey JSX 212 Combo amp at a Guitar Center at a killer deal - 999$ on clearance (spec'd as "new"). I absolutely fell in love with the sounds I could get out of it, and it is my first tube amp. The problem started when I took it home. I noticed a latent "buzz" sound, kind of like when you turn the TV on with you guitar in front and you get that "interference" kinda buzz. I tried moving the amp around, tried different outlets, different guitars. The sound is even there when there's nothing plugged in. Its intensity seems to vary mainly based on the Master Volume and Reverb knobs. When I move the reverb around, the intensity varies. Also sometimes the Send/Receive knobs in the back for the effects loop seems to effect the noise level of the buzz. Can someone please help me figure this out? Do I need to replace the tubes or something (the tubes are dated 09/06 when I looked at them)? I really love this amp and don't want to have to trade it in or sell it. Here's a clip of what I'm talking about:click Link to comment Share on other sites More sharing options...
Members Zacman0126 Posted October 18, 2009 Members Share Posted October 18, 2009 Hmm..when you moved it to other outlets, was it the only thing plugged into that outlet? Sharing an outlet with something like a mini fridge, or a freezer or tv can cause that. Link to comment Share on other sites More sharing options...
Members avirox Posted October 18, 2009 Author Members Share Posted October 18, 2009 Yeah it was the only thing plugged in. Even tried different rooms and got the same effect. Link to comment Share on other sites More sharing options...
Members Zacman0126 Posted October 18, 2009 Members Share Posted October 18, 2009 That's wierd. I don't know man...that doesn't seem like your average tube associated problem. If you have a spare preamp tube or even a set, swap them- never mind it just hit me, I think another forumite had this problem once and it was actually due to dirty loop jacks, try cleaning those. Contact cleaner + cable, then just put in and pull out a couple times. Link to comment Share on other sites More sharing options...
Members Blackwaterpark1 Posted October 18, 2009 Members Share Posted October 18, 2009 A friend of mine has the same problem with his JSX head. It buzzes and without the Mxr smart gate it's terrible, and even with it you can really notice it. He thought it was something hooked together wrong in his pedalboard, but he tried plugging in straight and got the same problem. Not sure what it is. I have a Peavey ultra 120 head and a Peavey valveking combo and I have no real noise issues that are major, and with my MXR smart gate it's dead quiet even at loud volumes. It may be something with that amp in particular. Check with Peavey or if someone in your area works on tube amps.... Link to comment Share on other sites More sharing options...
Members avirox Posted October 18, 2009 Author Members Share Posted October 18, 2009 That's wierd. I don't know man...that doesn't seem like your average tube associated problem. If you have a spare preamp tube or even a set, swap them- never mind it just hit me, I think another forumite had this problem once and it was actually due to dirty loop jacks, try cleaning those. Contact cleaner + cable, then just put in and pull out a couple times. What kind of contact cleaner (and brand) should I use? Also what do you mean by cleaner + cable (the cable part)? Blackwaterpark1: The amp has a built-in noise gate. Doesn't affect this probelm though (but it does cut down on the gain-related noise I get). Link to comment Share on other sites More sharing options...
Members Zacman0126 Posted October 18, 2009 Members Share Posted October 18, 2009 What kind of contact cleaner (and brand) should I use? Also what do you mean by cleaner + cable (the cable part)? Blackwaterpark1: The amp has a built-in noise gate. Doesn't affect this probelm though (but it does cut down on the gain-related noise I get). Doesn't matter, just look for contact cleaner. You can get it at some place like circuit city, radio shack, etc. Spray some cleaner into the jacks, get a speaker cable, plug it in, take it out, repeat. Link to comment Share on other sites More sharing options...
Members avirox Posted October 18, 2009 Author Members Share Posted October 18, 2009 Ok thanks I'll try that tomorrow. Also here's a wav I recorded with the hum: click Link to comment Share on other sites More sharing options...
Members Zacman0126 Posted October 18, 2009 Members Share Posted October 18, 2009 Ok thanks I'll try that tomorrow. Also here's a wav I recorded with the hum:click Check the solder points if the cleaning doesn't work. I would be looking at the ground points for failures. Link to comment Share on other sites More sharing options...
Members charveldan Posted October 18, 2009 Members Share Posted October 18, 2009 Ok thanks I'll try that tomorrow. Also here's a wav I recorded with the hum: click Do you live in an apartment bldg, or your own house??? If your in a apartment, your sharing the same power with everyone in the building, that means every flourecent screw-in type bulb [ which hum like a bitch], every coffee pot, computer, wall wart, ect, ect. Try taking the amp somewhere else like a friends house, and see if it does it there, also try other guitars, if you have them. Also do you have a tube for the reverb, like a 12AT7??? If you do, try a different tube. Link to comment Share on other sites More sharing options...
Members charveldan Posted October 18, 2009 Members Share Posted October 18, 2009 The JSX has a gate already, just use the gate and be done with it, it's an amplifier, it's not going to be dead quiet, if your playing your not going to hear hum anyway. Link to comment Share on other sites More sharing options...
Members Nate-Peavey Posted October 18, 2009 Members Share Posted October 18, 2009 Do you hear the buzz on the clean channel? Nevermind... just listened to your clip... Call Peavey customer service Monday morning, although it very likely a wall power issue if you didn't hear that noise at GC... Definitely try to take it to a different building. Was there a guitar plugged in when you recorded that? Link to comment Share on other sites More sharing options...
Members avirox Posted October 19, 2009 Author Members Share Posted October 19, 2009 Well it's getting sent to an authorized peavey repair shop now. I took it back to guitar center to see if we could figure out what was wrong. One of the guys there took out the power tubes and preamp tubes, cleaned them and reinserted them. That got rid of the hum for about 20 minutes, but then it came back >. Link to comment Share on other sites More sharing options...
Members BJMYJM Posted October 19, 2009 Members Share Posted October 19, 2009 HEY!!! I had the same issue with mine. It was like this for the year and half I had it. Two trips to authorized service centers and two trips to Peavey. The filter caps are fried. The PC board NEEDS to be replaced. Send it back to Peavey and ask for Rodger Crimm. You can contact him via the Peavey forums. PM me if you have any questions. Link to comment Share on other sites More sharing options...
Members magvike Posted February 10, 2014 Members Share Posted February 10, 2014 Use an adapter that changes it from 3-prong to 2-prong....works like a charm...hum is gone!! Link to comment Share on other sites More sharing options...
Members WRGKMC Posted February 10, 2014 Members Share Posted February 10, 2014 Lots of bad advice in this thread, but you did send it in whicg should have been the first advice. Theres no reason to have a newly purchased amp hum.The advice about contact cleaner was bad. You should always used lubricating contact cleaner that contains mineral oil for all electrical contacts and pots. Using zero residue contact clenaer can damage plastice parts like jacks and cause pots to be very noisy. The only time you use zero residue cleaner is to clean relay contacts, and since there are no relay contacts in most guitar amps it shouild never be used unless you want more problems then you started with.The advice about floating the ground is not good advice either. Do this in a live sitiation and walk up to a PA mic on a different ground loop and you'll likely get your ass kicked by120Vac through your lip.If the amp has an internal hum issue caused by the ground then its something that needs to be addressed internally. The reality is Peavey doesnt use high grade parts in most of their amps except in some of their higher end gear. The builds are not so hot either. As a tech I used to repair allot of their gear and its obvious to any tech who does repairs that peaveys are budget builds. This reflects in their ability to sell them cheap and thats why there are so many of them out there. The hum you have is likely a a tube bias issue or possibly a lack of shielding within the amp chassis. On older tube amp designs a chassis is grounded to shield all your internal components. Allot of newer tube amps have PC boards mounted to the chassis, and since the boards pass EMF the components are exposed to noise. The JSX seems to have more than its share of issues and even its built in noise surperssor cant block noise when its set for maximum. Some of the noise I'm sure comes from the amps high gain circuits amplifing weak signals to extremes, but again, those circuits wouldnt be anywheres near as noisy if the amp have higher quality components like Metal resistors vs carbon, High quality caps and shielded wire throughout. The only reason to build a noise supressor into an amp is because you know you have a crappy design with crappy parts and its acting as lysol to hide the stink of a turd.So my advice is, if you dont get back an amp thats hum free, take it back to the dealer and get something else. Link to comment Share on other sites More sharing options...
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