Musicman 75 head 2100EX too much overdrive

[blindboybenton]

Good morning too you all

I have a customer who has the above amp. I don't have it at present, but he is asking for me to come up with an idea to reduce the over drive

His was are the moment you turn it up there is too much OD.. We here in the uk don't see many musicmans. I think this is the correct schematic
musicman-amp-schematic-diagram-2100-65-chassis.pdf

Has anyone reduced the OD on these amps or any assistance

Have a good day and let be careful of those bits that bite

BBB

[J M Fahey]

The 2100/75 is here
Old Amps

1) set the master volume on 10

2) play with channel volume on 1 or 2.
Does the amp distort in a bad way? ... scope it and check what's wrong.

If clean:

3) start rising channel volume step by step ... does it start overdriving above, say, 4?
Is it quite loud?
Not wall shaking, just something you would not use in your living room.

Or, inject a 1kHz sinewave, scope the output, rise volume until clipping starts.

For the 2x6L6 version:

Do you get, say, 40W RMS or better?
Then he needs a larger amp.

Get 30WRMS or less?
Very old worn dead tubes, replace them.

For the 4x6l6: same, but double power.

Remember it has a Full/Half power switch, which lowers +V from 650/700V to around 400V DC

[blindboybenton]

Many thanks.

I don't believe the amp is faulty. He did tell me that he has replaced the output tubes. he wishes to reduce the over drive , Tame it some what. I was looking for thoughts on modding
before he brings me the amp

BBB

[g1]

Agree with JM, the overdrive is controlled by the ratio of channel volume to master volume.
It's confusing what he wants as he should be able to get anything from clean to distorted tone by adjusting those 2 levels.
Unless there is something wrong with the amp.
Can you find out what settings he uses for channel volume and master volume?

[blindboybenton]

its probably best that i get the amp to find out what is going on. Thanks for the input