Why don't no-load pots work as volume pots?

[Chistopher]

What's the science behind why volume pots can't be no-load pots, because I totally just did it on accident and it works fine. I feel the only reason people say it doesn't work is because no ones ever tried and just listens to strangers online.

 

[beaubrummels]

They can work as volume pots. They can be used for anything a pot can be used for. I actually use one as a blend pot on a Tele. People say they don't work on volume because they don't like the volume bump when you hit the detent and it snaps out of the circuit. The other reason is often they are audio taper.

 

[Mincer]

Yeah, I bet they work, it is just not a lot of people who use the volume knob regularly would like how it works or feels.

 

[Clint 55]

Because if you break the carbon strip at 10 near lug 1, the signal can't pass from lug 1 to lug 2 when the wiper is turned down.

Chris!

 

[beaubrummels]

Because if you break the carbon strip at 10 near lug 1, the signal can't pass from lug 1 to lug 2 when the wiper is turned down.

Chris!

I think you are talking about home-made no-load pots.

 

[Clint 55]

Lol! They work exactly the same way.

 

[beaubrummels]

Lol! They work exactly the same way.

Apparently not because my no load is a direct connection of the lugs at the top of the travel.

 

[Clint 55]

If the wiper on 10 doesn't get disconnected from any connection to the ground at lug 3 then it isn't no load.

 

[beaubrummels]

If the wiper on 10 doesn't get disconnected from any connection to the ground at lug 3 then it isn't no load.

That's what the detent is about, Clint.

 

[beaubrummels]

"For tone or volume controls"

https://www.guitarpartsfactory.us/E...ad-Split-Shaft-Audio-Taper-Pot?search=no load

 

[Clint 55]

Back to post 4, Bb. What happens if you turn down the wiper? Signal comes in lug 1, but there's a detent, or a break in the carbon strip. The signal can't pass in through lug 1 and make it past the detent / gap in the carbon strip to the wiper and out lug 2. Therefore, no signal if you try to turn down from 10.

 

[freefrog]

+1 about what Clint said: a no-load pot requires a cut/ a break between the carbon track and the external lug on the "full-up" side. Without it, it would remain a "load pot". The "detent" position is due to how the rotation is mechanically managed.

It can be checked with a DMM on a Fender TBX or Fender no-load control.

HTH.

 

[Chistopher]

See none of my TBXs actually measure no load in the middle. Two of them read 250k one read 1meg.

Also I measured the resistance between the input and ground terminals, and it reads 0 at 0, 250k at 9, and inf at 10, meaning the volume knob is bypassed at 10.

 

[marcello252]

if the wiper goes to the not connected dent you are connecting the pickup directly to the output, it works like an infinite pot if you want to think ike that, so you can use it like any other pot just expect, only with the pot on 10, a more pronounced peak on the resonance freq of the pickup

 

[freefrog]

See none of my TBXs actually measure no load in the middle. Two of them read 250k one read 1meg.

Also I measured the resistance between the input and ground terminals, and it reads 0 at 0, 250k at 9, and inf at 10, meaning the volume knob is bypassed at 10.

Passing my time to mount TBX controls, I'll repeat my statement: the 250k part of a TBX is a no load pot in center position (@5/10) as long as nothing is soldered to it. And it measures from 0 Ohm to 250k from 0 to 4.5/10 approximatively.
The 1M part offers a constant load, going from 0 ohm once the pot is @ 5/10 (and anywhere under this value) to 1M when the pot is @ 10/10.
It can be checked with a functional DMM + a TBX not yet mounted.

EDIT - BTW, I post this as an attempt to be helpful in the clearest possible way and not to argue: I'm way too busy for that. ;-)

 

[Chistopher]

That tracks, assuming you read your measurements the way the guitar would see the load.

If there's one important thing I learned from this whole experience, treble bleeds do actually have a noticeable effect on the tone even when the pot is on 10. I don't know about 500k and 1meg pots, but with my 250k volume there is an extremely obvious difference in the bass response when I'm at 250k versus when it's in the no-load position.

I thought my Wolfgang with a treble bleed sounded good, so I installed one in my Strat I've been messing with, and it definitely thinner out the bass response, even at max volume. I will be taking it off as soon as the non-no-load volume pot I ordered comes in. I'm experimenting with vintage taper, audio taper is too extreme on my already low output pickups.

 

[freefrog]

If a treble bleed has still an effect when a volume pot is @ 10/10, then the pot is not actually full up and still puts a residual resistance in parallel with the series cap. Might be interesting to check if the volume control is not defective in such a case. Because with a fully functional pot, 10/10 would put exactly 0 Ohm between center and outer/output lugs - and therefore, 0 Ohm between legs of the treble bleed cap, shorting it on itself and putting it out of circuit...

As a side note, I'll state that I also use no-load as blender pots : that's what I have in most of my Strats to blend the neck PU with the bridge one. I use indifferently "ready-made" or home made no-load pots for that.

But the wiring that I use puts the neck pickups out of circuit when the no-load pot are @ 10/10. From 9/10 to 0/10, the pot blends more and more of the neck PU to the bridge PU.

Like this: https://www.stewmac.com/video-and-i...rson-pro-cts-blenderno-load-pot-instructions/

In this configuration, the blender pot is nowhere connected to ground: it just mutes the "blended" pickup by putting it out of the circuit @ 10/10 (the center lug connected to one of the pickups to blend being now connected to a lug going to nothing and separate from the resistive track).

Using this as a master volume would be possible but it would "reverse" the normal rotation of a volume control, by giving full volume @ 0/10...

And for the record, there's a potential downside with no-load controls: how they might "pop" or "click" when passing from no-load to load.

FWIW. HTH.