Volume pot fast taper issue?

[candid_x]

The volume pot on my Axis Sport (older HSS style) tapers much too quickly, losing the body of its tone in less than 1/8 of a turn. I don’t experience this problem with my Silo, which has a wonderfully gradual taper. The Axis pot seems in sound condition, not broken or defective, from what I can tell.

What pot would you recommend I replace this with?

Thanks,
Bruce

 

[beej]

Which bothers you- the fast volume taper, or the loss of tone?

You can replace your tone pot with a linear taper, rather than audio taper pot- that will change the taper.

If it's the loss of highs when you roll back the volume, you can solve that one with a small capacitor across the lugs of the volume pot, to allow some treble to always bleed through to the output. (Do a search for "treble bleed capacitor", or check out Stewmac.)

 

[candid_x]

It's mostly the extremely fast taper. Not only the highs disappear too fast. More than touch of roll back and it's gone.

Thanks, Beej, I'll look into that.

 

[tommyindelaware]

cts tolerences are fairly broad. + or -15% i think. thats a possible variance of 30% so you might just try replacing the pot w/ the same value as the one u are happy w. it could be that simple.......

 

[candid_x]

Tommy, I am SO not a tech. Can you be more specific? Replace the volume pot with another of the same value? It’s the volume pot that I’m having trouble with, not the tone pot; just to be clear.

Thanks

 

[candid_x]

O, you mean replace the volume pot with a linear taper pot + or - 15%. I think I can even do that.

 

[tommyindelaware]

Tommy, I am SO not a tech. Can you be more specific? Replace the volume pot with another of the same value? It’s the volume pot that I’m having trouble with, not the tone pot; just to be clear.

Thanks

sorry !!!!
cts is the manfacturer.
i would first replace the questionable one w/ a new one that has the same value as the old one .

 

[candid_x]

Gotcha.

I spoke with local guitar/amp tech yesterday, who said the same as Beej: replace it with a linear pot.

 

[tommyindelaware]

you will find the lin. pot the turn up very quickly.

 

[candid_x]

This is what I’m uncertain about, Tommy. It seems most guitar makers use an audio taper pot. Why would they do that if there was this inherent problem with them? I don’t have this issue at all with my Silo Special, but the slightest turn down on my HSS Axis, and everything fades to dull.

 

[beej]

Audio (log) taper is a more natural taper for these applications. Tommy's probably right here, in that something is wrong with your existing pot or the tolerances are way off. (Or, somebody's soldered a resistor across the lugs which will change the taper.)

I'd just try a replacement pot- cheap, easy to solder in, or a few bucks for your local tech. Check the size of it- it's probably a 250k pot (but could be 500k).

 

[candid_x]

It's a 450 pot. The local tech is backed up for a couple of weeks, but I'll hand it off to him then. I've been reading a bit on it, and from what I gather I can brighten or darken the tone by the pot value - if that's the correct term? Interesting.

 

[beej]

450k? Did you measure it or is that what it says (that's an odd size). Normally the tolerances are +- 10-15%, so that sounds like it's a 500k that's not quite 500k.

There's lots of info on this site about that if you search. In a nutshell, more resistance (larger pot) will brighten up the sound, while lower resistance (smaller pot) will do the opposite.

Single coils are naturally brighter, so they tend to be used with 250k pots while humbuckers tend to be used with 500k pots. On combo guitars with both, usually 250k pots get used. But swapping in 500k pots brighten them up. There's no hard and fast rule, and a lot depends on the design and voicing of the pickups.

 

[candid_x]

Beej,

I appreciate your help in understanding this stuff. The pot itself has a number, some which is covered with solder (ground?), but what does show is: 450-AB??, and the tone pot is marked: 450-AB2505. I’m guessing they used the same pot for both volume and tone?

I don’t know what p’ups MM used for this older Axis Sport (w/pick guard), but it’s a HSS configuration, the bucker is a zebra. It looks completely stock to me.

With ash body and maple board, it’s on the bright side, but balanced, considering the wood. More definition than my Silo Special with rosewood board (naturally). If anything, I’d rather warm it up than brighten it. Maybe I should try a 250.

To clarify, the tone doesn’t entirely cut out when turned down, it just fades very quickly, gives little room for volume knob dynamics in a tune or jam. Not a problem with the Silo or any other guitar I’ve ever owned.

 

[beej]

No problem at all- everyone around here is pretty happy to help out.

Here's what I'd suggest: call MM customer service, and ask them if they'll send you a wiring diagram for your sport (they're really good about this). That will show the pot values, etc. and you'll know exactly what *should* be in there. If you want, you can then take that diagram to your tech and he'll put in the right thing.

Yeah- if you'd like to warm it up, you can put in a 250k in the volume. The tone pot may still be a little higher, but that will warm it up overall. If that's still not enough, you can lower the tone pot too. Other option is to adjust the pickup heights so that there's not as much treble.

 

[candid_x]

I like the 250 pot option, at least to try it out. And leave the tone pot be for now.

The pickup heights don't appear to be adjustable on this guitar. No adjustment screws on the pick-guard anyway. Maybe from beneath the guard. But I like the height they're set at. Quite hot and good sustain.

Thanks!