Is there a way to increase a pots value??

[nopainkiller]

I found this http://www.projectguitar.com/tut/potm.htm about reducing a pots value. And some cool treble bleeds, but I'd like to kneow if I could make my 500k pots higher.

[nopainkiller]

Also, on the passive mid scoop, mid boost and the mid scoop/boost pots. What are the best values? If I am using a 500K pot for the mid scoop with a 220k resistor and .033 cap in paralell into a grounded 1.5 milihenry inductor , should I increase the resistor value? Since the it was prolly designed for 250k pots. And how could I tweak the cap value? Would a higher value leave more highs? or would a lower value cap?

Any ways to tweak these three mod pots??

[tommy d]

When I mod wahs sometimes I'll put a resistors in series with the pot. let's say my 100k pot reads 90k and I want ideally 120k, I'll throw a 30k in series for a pot that reads 30k open and 120k closed.

I can't anwer the rest of your questions.

[Chuck H]

Also, on the passive mid scoop, mid boost and the mid scoop/boost pots. What are the best values?

JMHO but the Torres passive mid boost is a bogus circuit. There is no such thing as a passive boost. All it does is cut highs. It just cuts less highs than a standard tone control. His mid boost/cut control renders your guitars tone altered (cut at certain frequencies) at any setting no matter how close to center you try to place the knob. It is never far enough out of the circuit to avoid this. So if you want to hear your pickups and get all the harmonics out of your guitar, don't use the passive mid boost/cut control.

The mid cut control is an excellent circuit though. But despite his claiming it as "The Torres patented mid control" for years, this is an almost identical circuit as used by Gibson in their L5 guitars from the 70's. If it was patented, it wasn't by Torres. But he never did say it was his patent either. He only said it was patented. Still, I think it's a great circuit. There is a way to completely remove it from the pickup circuitry at the pots full rotation. You must remove the back of the pot and scratch through the carbon track where it meets the unused lug. Then you can use a 250k pot for a more predictable taper and still have no loading to guitars signal when the control is full off.

If I am using a 500K pot for the mid scoop with a 220k resistor and .033 cap in paralell into a grounded 1.5 milihenry inductor , should I increase the resistor value? Since the it was prolly designed for 250k pots. And how could I tweak the cap value? Would a higher value leave more highs? or would a lower value cap? Any ways to tweak these three mod pots??

The resistor is part of the tone balancing for the circuit and is not related to the pot value. The cap in the circuit is not responsible for the highs. The inductor is. If you want to tweak the tonal balance while the control is in use, here's how:

Decrease R value will cut more lows. Increase R value or remove it to increase lows

Decrease cap value to cut less mids. Increase cap value to cut more mids.

Decrease inductor value to decrease top end. Increase inductor value to increase top end. (Dan uses those little TL#### transformers from Mouser as inductors. Sorry I don't know the H value of any of those.)

I don't know of a good way to increase a pots value. Adding series resistors at either end would make it impossible to reach the pots full rotation. As in, you would never be able to turn it fully on OR you would never be able to turn it fully off. But since you know how to decrease a pots value, why not just start with a bigger pot and work down?

HTH

Chuck

[nopainkiller]

hey! that's some killer info thanks! I made a mid scoop/boost and installed it in my friends squire strat a while ago. When it's at ten, it seems like it IS boosted somewhere. It gets quieter, but harmonics get louder and trebly. I have the mid/scoop in my guitar.

Who's dan?? I need to ask him what value inductor he uses!!

And hey! Can i just scratch off some of the carbon on my other pots to leave the guitar circuit totally open???

[nopainkiller]

oh, dangit, my mid scoop is on a push/pull pot so I can assign it to either pick-up.

[pdf64]

Yes, I've scraped the carbon track (gently, with a scalpel) to increase the value of the 250k tone pot to turn it into a low load ~500k, or carry on scraping until the hot terminal is isolated, making it a no load. Keep a meter clipped on to keep a constant check on what you're doing. Peter.

[Chuck H]

I made a mid scoop/boost and installed it in my friends squire strat a while ago. When it's at ten, it seems like it IS boosted somewhere. It gets quieter, but harmonics get louder and trebly.

It's an illusion created by trimming the top end. At high gain settings an amp would then tend to resonate more in the upper mids as opposed to a more squeaky top end whistle. Thats why it seems like there's more mids. It seems boosted because it is by comparison to the cut settings. If you were to put one on a push/pull pot to disengage it and listen to the difference at clean settings you would hear what's going on. But that isn't to say it's wrong for you. It's just wrong for me. I like a very unadulterated brash tone. So even the awareness of unavoidable attenuation makes me squeamish. Even if it doesn't always sound like that.

Who's dan?? I need to ask him what value inductor he uses!!

Dan is Dan Torres of Torres Engineering, formerly of Torres Guitars. I knew him when...Long story. He's a good guy. A little grumpy at times but he does build some very good sounding circuits and they make people happy.

Can i just scratch off some of the carbon on my other pots to leave the guitar circuit totally open???

No the scratch trick will turn a pot used as a voltage divider (like your guitars volume control) into an on off switch. It only works on pots that are used as a variable resistor (like a tone or midrange control). The best compromise is something like a 1M audio taper pot for hot humbuckers or 500k for everything else. The Torres "Volume kit" is a decent taper fix/bright cap option that makes the controls range more predictable and natural.

You can take apart the push/pull pots. But I would sugest having a spare on hand to end up with a working circuit . I did ruin the first one I took apart. Small price to pay for the lesson and experience.

Chuck

[nopainkiller]

hey, is the volume kit just some .001 caps or .002 caps and resistors??

I've already got .001 caps on my volume pots. The volume pots are 1 meg and my tone pots are 500k. All push/pull. One assignable tone, one assignable mid/scoop, master bass contour, and two volumes parallel bridge option and phase on the neck. I wanna make my circuit as awesome and versitile as possible!

[Chuck H]

Thats alot of tone control at the guitar. If your using all those options in a practical sense (that is, not just "look what this can do" but you never really use it much) then it's very cool and versitile. I used to have alot of extra pickup phase, cut, series and odd tone control option on my guitars. But as I narrowed down what I actually use I find I much prefer a simpler setup. One volume, one midrange cut, and a coil tap pickup configuration (for humbuckers). I do like a series switch on strat type guitars to simulate humbuckers. But trimming down any extra knobs and switches helps me to hit the right tone quickly on stage. Thats just my bag. You know what you like. But I will comment on the volume control.

If your using push/pull pots on the volume control they are almost certainly linear taper pots. For everything but hot humbuckers a 1M pot will have a crappy taper. A linear pot makes this even worse. Plus a .001 cap is very bright. With a 1M pot a .001 cap would be much too bright IMHO. You can improve the taper and the natural response of the volume control by switching to a 390pf or 470pf cap and parallel a 220k resistor with it. Every guitar and amp is different, so experimentation is encouraged. But once you get the resistor capacitor combo right, so that you can turn down your volume knob with little change in actual tone from your guitar and a predictable taper, you will definitly experience more versitility.

Chuck

[nopainkiller]

ah, my volume pots are audio taper 1 meg push/pull pots. My mid scoop is audio taper 500k push/pull, and my tone is linear taper 500k push pull. I have parallel on the bridge because coil cut was too quiet. And phase on the neck, but I might switch it to parallell.

About the brightness, I did kinda notice a really bright, english like sound when I turned the bass cut all the way down, and the bridge volume in parallel and turned down a little. It's way bright. Like beatles Revolver bright. I love it!!!

[Chuck H]

Bitchin. Build a tone arrangement you love and rock on. The cool thing is that when your using a rig you've tweaked just for you, everyone listening gets the same vibe and thinks you sound great too. I used to get Q's on my rig from other players all the time. I loved it. Made me feel like a real hero.

Now I have a Q for you...Where in the world did you get push/pull 1M audio taper pots?!?

Chuck

[Enzo]

AES stock R-VPP-1MA



http://www.tubesandmore.com/

[Steve Conner]

OMG! I've been looking for one of those too. Thanks Enzo

Apologies for the OTness, but do you remember seeing an adaptor plate on the AES site for fitting a 9-pin miniature tube socket into an octal chassis hole? I need a couple but can't remember where I saw them for sale.

[Enzo]

Offhand I don't recall those. It would seem a small square of aluminum would work, cut a 9-pin size hole in it and a couple rivet holes and mount it up under the chassis - or on top. Maybe where you are you'd better use aluminium instead of aluminum. RoHS might not like plain aluminum.

I was thinking one of those metal can cap mounting plates might work. The holes tend to be square or triangle, but you could round it out. Then again a plain piece of metal might be easier to start with.

And what is there to lose, drop them line and ask. They might know what you mean and even have them off catalog.

www.tubesandmore.com