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markbass knob action

Hey guys, Just got a brand new Jeff Berlin combo and noticed that tha master volume knob doesnt have the same tight turning feel all the the other knobs have. It's not exactly loose. Just doesnt have the same solid tight turning action the others have. Wondering if anyone else has run into this.
 
love the amp. Everything works fine. Just the knob thing kinda bugs me. when you spend that much you expect everything to be perfect. its really no big deal. Certainly not enough to pack it all up and send it back.
 
All the knobs on my 121H combo (LMII head) and Little Mark III head have the resistance you speak of. I agree, it would make me wonder, too, if one felt looser. The question is, what gives them the resistance in the first place? Is it adjustable? I dunno. If it bothers you enough I'd send it back. Only you can decide.
 
The "feel" of a pot is due to a thick lube used between the shaft and the threaded collar. If this thick lube is thinned by using any spray lubricant or cleaner, it will turn easier.

In the manufacturing, it is possible that a pot might get too little of this thick lube and operate more easily.

If it turns easily, that's it. There isn't a fix, other than replacement.

Different manufacturers have different types of substances for this purpose. Bob Mackie used a "propriatory" lube on his first line of mixers, the original Tapcos. Unfortunately, the crap he used turned to a solid substance over a few years, and no cleaner or lube would loosen it. I have a letter from Mackie about this that explained what happened. He offered a big "sorry about that" concerning my now useless mixer.

Often different types of controls may be used in an amp...most controls from one line of pots, and one or more from a different line. This is common when linear controls are used for tone and other functions, and an audio taper pot is used for a master volume. (Line 6 Flextone for example.) Different product lines of pots, even from the same manufacturer may have different "feels" by design.
 
Some of those "propriatory" lubes are quite resistant to spray lubes and cleaners. Spray into the back of the pots, use only as much as is needed, and use non-spray when you have it. (I have Deoxit Faderlube in a needle container and prefer Faderlube, now renamed, to Deoxit cleaner.)

Blowing a pot with air to remove dust and then using a little lube is better than saturating dust with cleaner. When you dust at home, do you spray at the dust with Pledge and then let the mess of dust and Pledge sit there?

When working on old amps with controls long discontinued or of a style not easily replaced, I will remove the pot, disassemble it, manually clean the trace, lube the trace, reassemble the pot, and solder it back into the circuit. Unless the trace is cracked, this always works.
 
I just thought about wobbly Knobs and greasing pot shafts and all that rot chaps! All I have got to say on the subject is, vibrationary disconnects causing wear in the carbon track from, A dreaded tingling pointer contact.:eek:
If one were wishing to forever avoid all chance of this utterly destructive audio scenario occurring, it could easily lead to flutter on you bottom actually chaps! its all a matter of size (as you all know), you simply have to have a Jolly Jolly Big One like This::D
Link Removed
The pre amp master gain Knob goes up to 260 in vernier markings on a six inch dial, with a four inch diameter glossy black knob containing
a beautiful ball bearing mounted epicyclic 50 to 1 bronze reduction gearbox, driving a military grade Colvern LTD. heretically sealed nikel chromium wire wound potentiometer.
I know some of you chaps don't have very big ones that go up very far, unlike lucky old me!!! and sometimes a chaps prone to wonder about the reliability of his Knob, especially as it gets older.
Fear not i say! these days there fairly cheep, very small Chinese alps type clone pots available you could solder in instead.:D
 

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