Members JMR Posted April 18, 2012 Members Share Posted April 18, 2012 So, I got this ampeg V4 a little ago. Sound was decent, but the output was pretty low b/c the tubes were old. Well, after a few weeks of having it, I flipped on the amp and got that scratchy, very low sustain, dying-battery sound. I'm not sure if I did something to cause this or not. The new tubes I ordered arrived today. Nice quality 6L6GC - two tung sol SRs and two SED black labels and a 12DW7. Didn't fix the problem. Tried a mix of 7027A and the new tubes, still there. Swapped out the preamp tubes for ones I had in my peavey that are under a year old. Nope. I ran the sound out through the extension speaker output and the sound was just fine, no problems at all. Where could the issue lie? I'm at a loss! Any other trouble shooting I could do? Link to comment Share on other sites More sharing options...
Members ItchyFingers Posted April 18, 2012 Members Share Posted April 18, 2012 Not familiar with that amp, but is there a fuse that could need replacing? Bad tubes usually produce a nasty screeching sound, but I've had fuses fail that give me that squeaky mouse running away sound. Good luck, man. Link to comment Share on other sites More sharing options...
Members JMR Posted April 18, 2012 Author Members Share Posted April 18, 2012 I don't think that's it. But the fuse I replaced it with is 3 amp and it requires 6 amp. Now, when I turn it on, the sound is normal for like... 25 sec, then back to crap. switch channels, same deal. Link to comment Share on other sites More sharing options...
Members JMR Posted April 18, 2012 Author Members Share Posted April 18, 2012 ): Link to comment Share on other sites More sharing options...
Members ArrMatey Posted April 18, 2012 Members Share Posted April 18, 2012 I don't think that's it. But the fuse I replaced it with is 3 amp and it requires 6 amp. That could be your problem right there. You need to put in the right fuse. Link to comment Share on other sites More sharing options...
Members mhuxtable Posted April 18, 2012 Members Share Posted April 18, 2012 Put in the right fuse goober. Also, extension speaker out works but not the main speaker out? I'd start with that part of the circuit/check the input jack of the main speaker out Link to comment Share on other sites More sharing options...
Members Dr.Picklebottom Posted April 18, 2012 Members Share Posted April 18, 2012 whats a fuse goober? Link to comment Share on other sites More sharing options...
Members crowquill Posted April 18, 2012 Members Share Posted April 18, 2012 Maybe its the caps. If they're still the original caps in a 40 yr old amp, it wouldn't be unheard of for them to be toast Link to comment Share on other sites More sharing options...
Members insubordination Posted April 18, 2012 Members Share Posted April 18, 2012 Caps very well may be the culprit. I had a '73 V4 for 8 years or so and replaced the caps (including the originals) twice, once because it sounded like there was a constant thunderstorm in the amp. Link to comment Share on other sites More sharing options...
Members decode6 Posted April 19, 2012 Members Share Posted April 19, 2012 Caps very well may be the culprit. I had a '73 V4 for 8 years or so and replaced the caps (including the originals) twice, once because it sounded like there was a constant thunderstorm in the amp. That is what my '72 VT-22 is doing. It that a pricey fix? Link to comment Share on other sites More sharing options...
Members JMR Posted April 19, 2012 Author Members Share Posted April 19, 2012 Thunderstorm isn't the problem. Some of these sound like gradual things. My problem just popped up. also, the fuse that was originally in the amp was 6 amps. I through in a 3 amp for 5 minutes to see if a fuse was the issue. Link to comment Share on other sites More sharing options...
Members SonicVI Posted April 19, 2012 Members Share Posted April 19, 2012 Take it to a qualified tech. If there's a serious problem with the amp you could just end up exacerbating it rather than helping. Link to comment Share on other sites More sharing options...
Members lolque? Posted April 19, 2012 Members Share Posted April 19, 2012 If no one else's suggestions work, try changing inputs? Could just be a wonky connection. My vote is filter caps though. When they went on my v4, oh man were you able to tell. Link to comment Share on other sites More sharing options...
Members SonicVI Posted April 19, 2012 Members Share Posted April 19, 2012 Check out the sensitivity/hi/low rocker switches too. In my V4B those sometimes cause reduced output if they are dirty or not fully switched one way or the other. Link to comment Share on other sites More sharing options...
Members evets618 Posted April 19, 2012 Members Share Posted April 19, 2012 Fuses don't affect the sound, they either let the juice in or they don't.Your incorrect fuse (too low value) won't make it sound bad, but it will blow early. Worse is too large a value, because it will not blow when it should, and therefore will not do its job of protecting expensive parts of the amp from frying.That's all fuses are: 50 cent devices that prevent damage to $500 devices. Link to comment Share on other sites More sharing options...
Members insubordination Posted April 19, 2012 Members Share Posted April 19, 2012 That is what my '72 VT-22 is doing. It that a pricey fix? It took two techs and about $400, so, yes. But I also am not sure either really knew what they were doing. Link to comment Share on other sites More sharing options...
Members JMR Posted April 20, 2012 Author Members Share Posted April 20, 2012 Is it possible to suddenly blow any of those things? Link to comment Share on other sites More sharing options...
Members JMR Posted April 20, 2012 Author Members Share Posted April 20, 2012 rocker switches were the problem!!! Very finicky... speaking of which, how can I address that? in particular, the mid-switch. unless I firmly press it to ULTRA-HI, the amp gives me the dying battery sound. Link to comment Share on other sites More sharing options...
Members SonicVI Posted April 20, 2012 Members Share Posted April 20, 2012 They may just need a good cleaning. Open up the amp and spray some contact cleaner (deoxit) in there and rock them back and forth repeatedly. Link to comment Share on other sites More sharing options...
Members JMR Posted April 20, 2012 Author Members Share Posted April 20, 2012 They may just need a good cleaning. Open up the amp and spray some contact cleaner (deoxit) in there and rock them back and forth repeatedly. That's Plan A! Link to comment Share on other sites More sharing options...
Members JMR Posted April 22, 2012 Author Members Share Posted April 22, 2012 nevermind. Link to comment Share on other sites More sharing options...
Members oinkbanana Posted April 22, 2012 Members Share Posted April 22, 2012 It took two techs and about $400, so, yes. But I also am not sure either really knew what they were doing. I just had my orange OTR120 re-capped. 80$. you need to find new techs. Link to comment Share on other sites More sharing options...
Members JMR Posted April 23, 2012 Author Members Share Posted April 23, 2012 The search is on! Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.