Output Volume Knob Refit Kit

[topcat0399]

So i dunno about you......but, with me; the mark IV output knob is a bear to deal with.

First it has slop in it so you can turn it some distance before it actually engages the shaft and causes rotation.
I can probably fix that with a little TLC i suppose.

The real issue is when the shaft does actually rotate, man with this amp you gotta just TOUCH it and the output changes dramatically! Some times not enough but often TOO MUCH. Both situation causing need to further adjust with unpredictable results! In the heat of battle that's just way too much pressure .... girls are watchin! so.......

I'll take off the output knob, affix a BIG nylon gear, rig a smaller gear with a knob on it that I can crank with meaning to get the out put result that I want!

A big knob twist with small action! like normall amps!

so after I make it work who wants to buy one??? huh huh?

I'm commencing to calculate gear ratios....

 

[>Photi G<]

Usually a new pot will help. Thinking about installing a new master pot on my III as well, as it is touch sensitive as well. The stock pots used on these amps were rather cheap, since they are push/pull.

 

[Boogiebabies]

The Mesa replacement part number is 596821 for the output pot.

 

[topcat0399]

So you guys are saying that my output pot is bad!?!?

I gave myself the impression that... that was an inherent downside with a mark series amp;
dramatic output change with a very smalltwist of the output knob.....

Not true?

My little black monster is defective? Say it ain't so (or better say it IS so!).!!!

The difference in output from say "1" on the knob to "1.25" on the knob about knocks me over.
Not normal???

I would just like to be reassured before I launch an unneeded repair.

Thanks for your advise.

 

[Boogiebabies]

It's a 250K Audio Taper. You just never know when the taper begins. No one said it was bad, but it could be 20-30% out
of tolerance to start. If your lucky you will get a replacement that goes more even from 250K to 0. We have all dealt with this
issue before.

 

[ricomock]

S

The difference in output from say "1" on the knob to "1.25" on the knob about knocks me over.
Not normal???

I would just like to be reassured before I launch an unneeded repair.

Thanks for your advise.

Yes

As other have said it's the taper the pot has