mika
Full Member
Posts: 182
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Post by mika on Dec 5, 2011 22:07:47 GMT -7
Hey fellow Z people... a while back I posted that I had some reverb noise with my maz.... here is my report back after some noodling.....
I tried a new tube in v3 and v4 which did not help..... I have used some De oxit on the points of contact, which has not helped. I removed the reverb tank, and tried repositioning it, which did not help I begged the reverb just to sound less noisy and it did not work.
Any suggestions? Its picking up low radio signal, and just has alot of noise and hiss. Not buzz, not hum. But its a noise thing, like a radio that is not tuned in right. Static.
I dont use the reverb, but I would like to conquer the problem.
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Post by jlc on Dec 5, 2011 22:27:20 GMT -7
Is this a new amp, was it playing ok for a period of time and then started making the noise.
Some may differ but i think reverb tanks are fairly fragile, so was it moved around, shipped etc., because I did have a Super Reverb that one of the spring ends broken, most likely in shipping.
Have you looked at the reverb springs? Intact etc.
Answers to the above might help one of the much more qualified on this forum, provide you with their thoughts.
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Post by tjnies on Dec 6, 2011 5:59:32 GMT -7
I'll be watching this thread, as lately mine is doing the same thing. Tried changing tubes out, De-oxit, etc, but no change.
At first I thought maybe it was just the single coils in my Tele, but it's the same with humbuckers.
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Post by BritInvasion on Dec 6, 2011 12:35:47 GMT -7
I recall a thread similar to this a long time ago. IIRC , the problem turned out to be the connection in the reverb tank where the wires attach. Apparently there is a solder joint / connection point that can get a hairline crack a wreak havoc with noise and intermittent failures. Maybe another member can remember the details , but as I recall sometimes reflowing solder at the joint took care of it , other times the tank had to be replaced.
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Post by Scott on Dec 6, 2011 23:16:10 GMT -7
Looking around I found this old post...
I have no idea if the info is still valid. The Jr. may have been changed since then?May 2005 guitargeorge wrote: The reverb hum issue can be fixed by isolating the reverb jack mounted on the chassis from grounding on the chassis. (the reverb jack to be isolated is the one with the resistor connected to it) I removed the resistor carefully so I could reuse it, then removed the jack, made the hole in the chassis slightly larger and using an "o"ring and two nylon washers to isolate the jack from the chassis I reinstalled the jack. At this point check with a meter to see if the jack is not grounding to the chassis and then reinstall the resistor and on the ground side of the jack a piece of wire to run your new ground. I grounded the wire to a post on the board where the reverb grounds to but I heard you can also solder the wire to the reverb pot casing. This done and I had no more reverb hum, which was minimal at the least but still an annoyance when playing at low volumes. hope this helps.If you find it to be still valid, let me know and I will record it in the troubleshooting section.Also found this post on reverb hummm squishycat wrote: I think I've found the problem. The transformers are inducing the hum. I have the head version, so space is a little cramped. I can adjust the alignment of the unit with the transformers to minimize the hum, but it seems there's no way to fully get rid of the hum other than moving the reverb unit outside the head.
Oh, well.
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eleloy
Junior Member
Posts: 81
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Post by eleloy on Dec 7, 2011 1:12:55 GMT -7
try removing ALL the tube covers... It seems silly but it works.
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Post by guitargeorge on Dec 7, 2011 5:00:45 GMT -7
I'm the author of that post, I had a MAZ 18 from the early-mid 90's and it seems that back then they all had a grounding issue with the reverb. I think Dr. Z corrected the problem on the newer amps. The hum was barely audible but you could hear it when you were practicing at home, in a noisy bar it was'nt an issue but isolating the jack from the chassis and regrounding it was the cure. Since then I've had some problems with the reverb circuit such as a dirty reverb pot that cause weird amp break up, and one time the amp was too close to some wiring in the house that caused a hum, actually now the amp hums a bit in some places and not at all in other places, so it may be where you are at. Try different locations, my living room has all kind of interference but my bedroom has none. TV's and computers, lights with dimmer switches, and old wiring inside of the walls will do it. I had some Christmas Lights that changed patterns plugged in on my front porch light that was wired to a ceiling fan in the living room that was wired to my bedroom circuit and the ceiling fan caused fluttering amd the christmas lights made a series of noises that was in a pattern that corresponded to what the lights were doing, I have a post on here somewhere explaining the problem.
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Post by guitargeorge on Dec 7, 2011 5:07:15 GMT -7
also try an old stock 12AT7, it's hard to find good ones that are new for the reverb circuit, also make sure the top chassis cover is tightly bolted down, that seems to cause problems with RF, also a clip on choke on the reverb tank wires may help. Radio Shack got them.
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Post by akhurshi on Dec 21, 2020 11:42:52 GMT -7
I was getting a whistle noise from reverb when I increased the Reverb on my Maz 18. The quickest and easiest thing to do is to take out the reverb tank from the amp and move it as far as possible with the wires still connected. When I did that the noise went away. I ended up attaching the reverb tank on the outside on the side away from the transformer.
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Post by Jaguarguy (Mike) on Dec 21, 2020 14:50:46 GMT -7
Somewhere there is a thread about making a shield for the reverb tank that seemed to work well. I'll have to look.
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