Need a little Wizard amp help --Problem

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Panhead5

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I recently picked up a late model MCII and I noticed it has a percussive thump through the speakers on the lead channel when you attack the strings. It's definetly not right . I know there's a lot of smart amp people here and just want to be headed in the right direction. It's only on the lead channe land I noticed it does come and go but it's there most of the time. I was thinking a preamp tube but one of my amp gearhead junkies thought it might be a cap. Trying to find a course of action .

I don't think it was intentionally sold to me with a problem but I can say the last thing I want to do is send it back to Wizard.
 
Haven't heard this issue before, but as above is the first step, then replacing the preamp tubes one by one with a known good one is next. Past that it may be time for a tech.

You do not have to send it back to Wizard. Any competent tech can work on any quality tube amp - that's the beauty of them. Doubtful it's a big deal. Good luck, let us know how it resolves.
 
Thanks for the replies -- George Iwant you to know you were right you can hear every note in a chord . Zen your video with a bunch of different cabs was inspiring . Now if I can get it to work right.....................
 
Greazygeo said:
Make sure all the tubes are seated if you haven’t already.
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This and also check that the tube socket receptacles are not corroded or too loose/open. Could need cleaning and re-tightening. If those power tube pins aren't tight in the socket receptacles or there is corrosion, or both, you could experience a loud crack/thud like sound which is likely some form of arching.

Be careful messing with the socket terminals/receptacles until you discharge the caps. They should bleed off on their own in less than a few minutes, but I always test with a meter!
 
Panhead5 said:
I recently picked up a late model MCII and I noticed it has a percussive thump through the speakers on the lead channel when you attack the strings. It's definetly not right . I know there's a lot of smart amp people here and just want to be headed in the right direction. It's only on the lead channe land I noticed it does come and go but it's there most of the time. I was thinking a preamp tube but one of my amp gearhead junkies thought it might be a cap. Trying to find a course of action .

I don't think it was intentionally sold to me with a problem but I can say the last thing I want to do is send it back to Wizard.
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Take advantage of this moment to crank the amp and destroy those palm mutes! Ride it till the wheels fall off. I suggest the suffocation riff, or spheres of madness by decapitated
 
MetalHeadMike said:
This and also check that the tube socket receptacles are not corroded or too loose/open. Could need cleaning and re-tightening. If those power tube pins aren't tight in the socket receptacles or there is corrosion, or both, you could experience a loud crack/thud like sound which is likely some form of arching.

Be careful messing with the socket terminals/receptacles until you discharge the caps. They should bleed off on their own in less than a few minutes, but I always test with a meter!
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I think you gotta be a little careful with caps; unless you discharge them properly they can still hold a charge. The best 'I'm gonna risk it' move is to play the amp, and while playing turn the amp off without putting it on standby..keep strumming and you'll hear the sound fade away...doing it that way will only leave around 9v left so if you do shock yourself, it's not as bad as it could be.
 
Racerxrated said:
I think you gotta be a little careful with caps; unless you discharge them properly they can still hold a charge. The best 'I'm gonna risk it' move is to play the amp, and while playing turn the amp off without putting it on standby..keep strumming and you'll hear the sound fade away...doing it that way will only leave around 9v left so if you do shock yourself, it's not as bad as it could be.
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Every amp I've owned, including Wizards, has self drained very quickly the moment power is flipped off. Just test with a meter, or drain using a meter set to proper voltage. I don't recommend if a person has no electrical experience, but if you have some, it's really pretty simple.
 
All you have to do to drain caps is like Racerxrated said…play the amp and turn the power off leaving the standby in play position….keep playing till you hear no sound…they are drained At that point.
 
Panhead5 said:
Thanks for the replies -- George Iwant you to know you were right you can hear every note in a chord . Zen your video with a bunch of different cabs was inspiring . Now if I can get it to work right.....................
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Good deal. Hope you get it working without too much trouble, should be something simple.
 
is this an audible thing or is it a feel issue? if audible post a clip, there are some knowledge techs on this forum that might be able to sort it out
 
MetalHeadMike said:
Every amp I've owned, including Wizards, has self drained very quickly the moment power is flipped off. Just test with a meter, or drain using a meter set to proper voltage. I don't recommend if a person has no electrical experience, but if you have some, it's really pretty simple.
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Before I learned to turn off/play till the sound fades, I did zap myself trying to change bias circuit by piggybacking a cap so I could use 34s( I think lol; been 10 yrs)....it was a pretty good jolt too. I mistakenly touched my small flathead on a cap wire..so at least, in my experience turning a Marshall off without doing that drain does leave a nice amount of voltage in.
 
lespaul6 said:
is this an audible thing or is it a feel issue? if audible post a clip, there are some knowledge techs on this forum that might be able to sort it out
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It's audible -- but it temporarily went away . I need to get a good look at the tubes to make sure nothing happened during shipping although it was packed extremely well . I'm a little pressed for time but put this at a high priority to get squared away .
 
Ya, the pre-amp tubes probably shifted during shipping and came unseated partially. It happens all the time. They're rough with shit at UPS or USPS.
 
anomaly said:
Ya, the pre-amp tubes probably shifted during shipping and came unseated partially. It happens all the time. They're rough with your shit at UPS or USPS.
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only stopped in to say,....this feels like a MMDan joke in here... smile

hope you get your amp squared away.
 
psychodave said:
My 67 plexi holds voltage for quite a long time.
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Yeah, many older amps don't have bleeders built in the circuit I'm sure. That's why I test with a meter regardless. I'd never assume something isn't hot regardless of voltages. If folks don't have electrical experience/knowledge, better off taking it to a tech for sure. I was bit hard once in my younger days when I first started working on appliances, I was lucky and learned real quick...it not only hurts, it can kill ya.
 
UPDATE : As I've attempted to resolve this concern with the amp I checked all the preamp tubes and they appear to be OK but I noticed this problem only occurred when I was using my Suhr KOKO boost. That doesn't make a bit of sense but I noticed when it was off I didn't have any problems . I need to keep working on it. I don't run monster gain so I'm not sure what 's up .
 
Panhead5 said:
UPDATE : As I've attempted to resolve this concern with the amp I checked all the preamp tubes and they appear to be OK but I noticed this problem only occurred when I was using my Suhr KOKO boost. That doesn't make a bit of sense but I noticed when it was off I didn't have any problems . I need to keep working on it. I don't run monster gain so I'm not sure what 's up .
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Using a power supply with the pedal? Could be a ground loop kinda deal.
 
I'd hit up some contact cleaner on a 1/4" guitar jack and work it in and out of the footswitch jacks just to make sure its not a bit of corrosion causing channel bleed from the rhythm channel, that percussive sound when you hit hard could be some of the clean channel bleeding through. I had that issue with an old Ampeg Lee Jackson amp and that took care of it.
 
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