tone pot selection

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Andy Henriksen
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tone pot selection

Post by Andy Henriksen »

I know this is guitar wiring 101, and it's probably been addressed here 1000 times, but I'm still unsure...

Assuming I already have a linear taper pot, if my guitar has too abrupt of a change in tone (approx. full change in 10% of the rotation; 2 through 10 changes nothing), will dropping to lower pot rating help spread that change over a larger rotation?
Brandon Minnix
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Post by Brandon Minnix »

The rule of thumb I've seen here and other places regarding tone pots (and the rule I used which worked quite well) is that your tone pot should match the same value as your volume pot with the exception of the taper type (Volume = Audio, Tone = Linear). The values of these are rather standardized based on the type of pickups you are using (not set in stone however) and also determines the size of the tone pot capacitor.

Are you using that standard method or just a, "I have this pot, does it work?" method?

From what I've read/used, single coil pickups benefit greatly from 250K pots and a .047uF cap, whereas humbuckers/doil coil pickups benefit the most from 500K pots and a .022uF cap.

I personally used this set up on mine, and it seems to work flawless. Again, nothing against discovering your own route/sound, but it seems a good starting point.
Andy Henriksen
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Post by Andy Henriksen »

Well, I want a sort of abrupt change, like over 25% of the rotation so I can do some boo-wah sort of stuff, but right now, it's almost instantaneous.

I'm not with my guitar at the moment, and I don't recall which pot I used. It's either 1M or 500K linear taper.

So, I'm just trying to understand, all other things being equal, what the effect of changing the pot to a lower value will be, and if it'll help "spread out" the tone adjustment.
Last edited by Andy Henriksen on 2 Jan 2018 8:42 am, edited 1 time in total.
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Stefan Robertson
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Post by Stefan Robertson »

Stefan
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Andy Henriksen
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Post by Andy Henriksen »

Stefan Robertson wrote:This should help you?

http://www.hawaiiansteel.com/instruments/diagrams.php
It probably should, but it doesn't! :lol:

The first three I clicked on had 100K, 250K, and 1M tone pots! And I have not played any of those (other than a stringmaster), so I don't have a clue which guitar's tone knob response I would want to emulate.
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Stefan Robertson
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Post by Stefan Robertson »

Stefan
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Mike Neer
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Post by Mike Neer »

Lowering the resistance will not change the abruptness of the tone change. Using an audio taper pot will make it more gradual. Use a log/audio taper as opposed to a linear.
Andy Henriksen
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Post by Andy Henriksen »

Mike Neer wrote:Lowering the resistance will not change the abruptness of the tone change. Using an audio taper pot will make it more gradual. Use a log/audio taper as opposed to a linear.
THANK YOU!
Brandon Minnix
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Post by Brandon Minnix »

Yeah, I was about to suggest the same for a boo wah effect. Based off of what I've read solely, not experience.
Brandon Minnix
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Post by Brandon Minnix »

The more I think about it, even with a linear taper pot, you should get less than an instant full on in 10% rotation. By the way it sounds, when the actual wiper makes contact you're getting full juice instantly.

Within that 10% rotation, is there any variance? Like, if you turn it 1% - 5%, is there a difference than at 10%?

If not, it could be incorrect wiring I suppose. Since the tone pot doesn't use a reference voltage, I'm not sure that the resistance value of the pot matters that much as it's all relative to the signal it's getting from the volume pot.

I could be completely off base here, I'm not an electrical engineer, but do a bit of dabbling in it.

The audio taper vs log taper should give a difference in how fast it goes up, but I'm pretty sure that getting full tone in 10% rotation with a linear pot is not normal.

100% Audio SHOULD equal 100% Linear. It's just the path they each take to get there that varies.

EDIT: For a boo wah effect, I still concur that an Audio taper pot should be used (based on research), I'm just not sure that if you wire it the same way, you won't get the same result.

EDIT #2: Clarification, the value of the tone pot will matter, but only on the overall clarity/muddiness. A higher value pot will give you more clarity at max than a lower value pot at max, however the travel from 0 - 100 should still be noticeable almost all the way through the range.
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Stefan Robertson
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Post by Stefan Robertson »

Reason I suggested those sites was it sounds like your wiring is wrong.

Myself as well as others here in the UK in Denmark street had a fun jam back in the day and I remember a bunch of random steels from Fender champs to Gibson to Gretsch to many others even Goldtone and Cheapo Artisans being able to Boo Wah when we were playing around.

Haven't used the effect recently but surely all of those didn't have the same wiring.
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Stefan Robertson
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Post by Stefan Robertson »

If I remember correctly one of Cindy Cashdollar's Dvd's she shows you the technique for a Boo Wah. I'll double check and let you know which one I have the videos and will see if I can find the snippet.
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Brandon Minnix
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Post by Brandon Minnix »

Yeah, from what I've read, the boo wah can be done with either type, just is supposedly "easier" to do with an audio/log pot since the taper rises faster then levels off vs a straight line from point A to B and I don't think you have to swing the pot as far to get the effect you're going for.
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