MT-200 is actin up

[Dante]

So, I played a back yard party with my now defunct cover band on Saturday. I had both 1x12 cabinets, one on each side of the yard, and I wasn't mic'd so I had a true stereo sound  :whoohoo!:

I noticed channel B was much quieter, and I had to compensate by turning it way up (volume was at 3:00, while chA was at 12:00). Yesterday, at home, I tried each channel independently and found chB to be much quieter and the sound is pretty muffled. Makes me wonder if this is coming

I have yet to tear apart the rack to see what's going on inside....but I will get there I guess

[Harley Hexxe]

I've noticed that on a couple of my MT200's as well.

[MarshallJMP]

Try to clean the mono in and bridged out jacks.These jacks have contacts inside that control that CD4053,if something goes wrong here you can get some weird behaviour. Try it out and let me know.

[Harley Hexxe]

I will try that on mine, but I need to get some Deoxit cleaner. I don't have any of that :dunno:

   Harley 8)

[Dante]

Try to clean the mono in and bridged out jacks.These jacks have contacts inside that control that CD4053,if something goes wrong here you can get some weird behaviour. Try it out and let me know.

Thanks MJMP! I'll try to find my deoxit to clean those babies up - I just moved, can't find a fricken thing! I'm suspecting it's pretty dusty in there, so I'll swing by the electronics store for some air. It would be pretty cool if that's all it is.

[MarshallJMP]

Well here I use 3 different cleaners now.

Kontakt 60 removes oxidation

Kontakt WL remove the residue of the oxidation

Kontakt 61 lays a protective layer on the contacts.

But I don't know if these are available in the US.

[Dante]

I don't know either, but I bet I can find something comparable by looking around - there's a very savvy electronics store in town, they'll know what I'm looking for.

UPDATE: The MT-200 sounded fine at practice last night  :dunno:  but I was admittedly turned WAY up  :banana-rock:  for ZZ Top practice. (the drummer has a particularly loud snare  :o )

This makes me think it could be a contact acting buggy. I didn't unplug the input/output jacks on the amp, but I did move them around a bit when hooking up the cabs and packing up the rack. It may have jostled the connection into working better at practice. I think a good cleaning is in order

[MarshallJMP]

Yes I think so too. These jacks are getting old. The best way would be to replace them. Did some looking around and you still can get these except for the bridge out jack. This is something special and I did found one but with solder lugs and not the pcb version.