Pot tapers, resistance value and capacitors

the_jaffa

I'm getting to the point in my guitar build where I need to start figuring out the wiring but I'm a wee bit lost. I need to buy a pair of pots, one volume, one tone and I also need to cap for the tone pot.

The setup I'm going for is a pair of humbuckers, a three way switch and a pair of mini switches for splitting the coils and it is this splitting that is confusing me. If I just had the humbuckers then I'd probably be going with 250k or 500k pots but due to the splitting option I'm not sure whether this would work ok or not. I guess the middle ground of 500k makes some sense but could do with some back up on my thoughts from someone more knowledgable.

The splitting also seems to confuse things on the tone pot cap. With humbuckers it seems to be that a 0.047 cap is the recommended option but with single coils it seems that 0.022 caps are a better option. Any thoughts as to which would be better in my situation?

On the taper front, I understand that an audio taper for the volume pot makes sense and that a linear taper makes more sense for the tone pot but can anyone help back that up, confirm or deny please?

Any advice would be greatly appreciated, cheers.

Mkjackary

I would go for 500k, split humbuckers are usually designed for 500k pots (well tested with them anyway).

Again with the tone the 0.047uf will get you a darker tone, and the 0.022uf will get you less dark (less high frequencies taken out). I would never use a 0.047 cap at full whack, not musical at all to me, so I use 0.022 on everything, humbuckers and single coils. There is no right or wrong answer.

For taper, you have got it spot on imo, audio taper for volume, linear for tone.

Mkjackary

I really like the montreux wiring kits on thomann, very high quality parts, all in one kit, including solder and very nice wire. Cheaper than buying everything separately. 

Although just looked at your build and they don't have something for it, 

I'd go for

cts 500k pots, one audio one linear,

switchcraft jack

orange drop cap 0.022uf (partially because they look pretty, any old one will do, but it is nice knowing there is a massive orange thing in your guitar).

I would say pushback cloth wiring but you have a load of switches and the wire with the cloth is quite thick compared to normal insulated wiring. 

the_jaffa

That's great info, cheers. Looks like I was mostly on the right tack. I'll go with a 0.022uf cap and 500k pots.

How much difference does the actual cabling within the guitar make? I read on here a while back about splitting an old scart cable and using the wire in that for hook up but having done that the cable that it has yielded seems very fine gauge so not so sure. The braided vintage stuff looks cool but will it actually make any appreciable difference other than "mojo"?

Mkjackary

Actually yes. I haven't made a direct comparison so couldn't say about a difference tonally, but pushback cloth wire is, for me, a hell of a lot easier to solder with, no more wire strpping, just cut it to length, pull the cloth back, solder, trim the ends, then push the cloth back over it, and it is fully covered up.

Just had a look at your routing too and it will definitely fit. something like this is what I would use (although maybe a cheaper/different colour/length) http://www.ebay.co.uk/itm/22-Ga-Stranded-Cloth-and-Wax-Covered-Guitar-Wire-2-foot-lenghts-/171470841624?var=&hash=item27ec756718:m:m4vxmSzDjMw_0GNHA5QceaQ

I prefer this stuff to the braided gibson type wire.

the_jaffa

Nice one, cheers for that link. Think I'll get me some of that.

Sporky

You can use 500k pots with single coils too - they'll just be a bit brighter. Well, there's a more involved description, but that's basically not-untrue.

ICBM

Absolutely NOT linear for tone - it will act almost as an on/off switch at the bottom end of the range. This is a really common misconception, but if you think I'm wrong, please just try both and tell me which works best .

Log for tone, always. The only exceptions are if you deliberately want a very short travel for 'hand wah', or for a jazz guitar where you want a restricted range at the bassy end using a much smaller-value pot than normal. (eg 100K or 50K.)

Log or Linear for volume depending on how you like the taper - Log is better for cleaning up an overdriven sound, linear is better as an actual volume control for a clean sound.

You can use different values if you want, even if the most common is to have both the same. I never like the tone control to be lower value than the volume, that just gives a reduced tone range which you can get from a higher value just by turning it down a bit anyway. Personally for a splittable humbucker with single volume and tone setup my favourite combination is 250K volume, 500K tone with a .047uF cap - to me that gives the most natural sound in both settings combined with the widest range of tone control.

the_jaffa

Hmm, that sounds like a pretty definitive opinion on the tone pot taper. I'll order a couple of each so can try it both ways and see how I get on.

Interesting comments on the values in your last paragraph too.

Cheers

Mkjackary

ICBM said:

Absolutely NOT linear for tone - it will act almost as an on/off switch at the bottom end of the range. This is a really common misconception, but if you think I'm wrong, please just try both and tell me which works best .

Log for tone, always. The only exceptions are if you deliberately want a very short travel for 'hand wah', or for a jazz guitar where you want a restricted range at the bassy end using a much smaller-value pot than normal. (eg 100K or 50K.)

Log or Linear for volume depending on how you like the taper - Log is better for cleaning up an overdriven sound, linear is better as an actual volume control for a clean sound.

You can use different values if you want, even if the most common is to have both the same. I never like the tone control to be lower value than the volume, that just gives a reduced tone range which you can get from a higher value just by turning it down a bit anyway. Personally for a splittable humbucker with single volume and tone setup my favourite combination is 250K volume, 500K tone with a .047uF cap - to me that gives the most natural sound in both settings combined with the widest range of tone control.

See I probably use tone knobs in a different way to you, I never go full jazz, and have never found any usefull tone with the knob all the way off, so I went for a 0.022 and all it did was make it easier to use the tone knob, as less of the range is just mush.

I tried out a linear and an audio log pot on a les paul (one on each pickup) and much prefered the linear. The tones I use were much easier to find with it. I always struggled to get enough happening with log, then it would be muddy all of a sudden, and finding the sweet spot was hard. For me the linear was easier. Although that was using a 0.022 cap for both.

Also I have had a go at using a 250k with a humbucker and didn't particularly like it, tried a 500k with single coils and it is cool, and I would use that under certain circumstances, the more high end is great, sometimes it is useful other times when it isn't you can just roll the tone off. The 250k volume with the humbucker wasn't dark per se, but just not sitting where I would want it to sit without changing the eq of my amp every time I change guitar between that and a different one.

I guess there really is no wrong way.

Edit - Just drew a log and linear graph and to my eyes I would almost certainly have chosen the log pot because of how it rolled on. But to my ears I prefer the linear pot.

ICBM

Fair enough if you've actually tried it .

I find linear useless for a tone control because it does nothing from 10 down to about 3 and then all the range is compressed into the last quarter turn so it's hard to find the sound you want. Log gives an even change all the way down, and more control over the range where there is only a tiny bit of treble rolled off.

Interestingly you *do* use the tone control exactly like a jazz player! Which is why Gibson used 100K Lin on some of their guitars and Fender used 50K Lin on the Jaguar/Jazzmaster 'rhythm' circuit.

I do really think that the advice to use linear for tone is almost universally wrong though. Most players never use their tone controls, and one of the reasons for that - going by what I've been asked to fix so many times over the years - is exactly because the range is too abrupt at the bottom end, which is what happens if you use a linear pot.

Not helped by many low-quality Logs actually being made from two sections of linear track, either...

the_jaffa

ICBM said:

I do really think that the advice to use linear for tone is almost universally wrong though. Most players never use their tone controls, and one of the reasons for that - going by what I've been asked to fix so many times over the years - is exactly because the range is too abrupt at the bottom end, which is what happens if you use a linear pot.

That's a very interesting point. I rarely use the tone control and probably for exactly that reason. Hmm.

tabbycat

the_jaffa said:

I'm getting to the point in my guitar build where I need to start figuring out the wiring but I'm a wee bit lost. I need to buy a pair of pots, one volume, one tone and I also need to cap for the tone pot.

The setup I'm going for is a pair of humbuckers, a three way switch and a pair of mini switches for splitting the coils and it is this splitting that is confusing me. If I just had the humbuckers then I'd probably be going with 250k or 500k pots but due to the splitting option I'm not sure whether this would work ok or not. I guess the middle ground of 500k makes some sense but could do with some back up on my thoughts from someone more knowledgable.

The splitting also seems to confuse things on the tone pot cap. With humbuckers it seems to be that a 0.047 cap is the recommended option but with single coils it seems that 0.022 caps are a better option. Any thoughts as to which would be better in my situation?

On the taper front, I understand that an audio taper for the volume pot makes sense and that a linear taper makes more sense for the tone pot but can anyone help back that up, confirm or deny please?

Any advice would be greatly appreciated, cheers.

hey jaffa, am just about to start wiring a project with exactly the same set up and wondered where you get your reliable wiring diagrams?

while i think i understand what to do (having built quite a few stompboxes), rather than guess (or use someone else's guess) it would be nice to have a guaranteed bullet-proof wiring diagram to avoid messing up.
as to pot values, others know better than me and i will learn and take notes. the splitting thing confuses me too. do i need a separate cap for the 7k single coil and the 14.5k double coil of each humbucker is what i'm stuck on.

good luck with yours.

the_jaffa

@tabbycat

I've been using the diagrams on this page:

http://www.guitarelectronics.com/category/wiring_resources_guitar_wiring_diagrams.2_pickup_guitar_wiring_diagrams/

Seem to be pretty well laid out and there's a whole load of options that should cover most stuff

tabbycat

thanks for the lead, jaffa.

have been looking at various schemes across forums and websites but never sure how reliable they are. don't want to put the whole thing together, string up, then find i missed a ground and have to strip right back down. stompboxes i'm confident with but amps and guitars trip me up.

hope progress with your squire jagmutant is flying along.

ICBM

tabbycat said:

do i need a separate cap for the 7k single coil and the 14.5k double coil of each humbucker is what i'm stuck on.

No, one is fine. It *is* possible to use extra switching to do things like cap values and pot resistance, but it gets very complicated and the benefits are fairly marginal unless you're very fussy. Of the two the volume pot value is more important.

For the tone control it's usually best just to choose the values that work best for the sound you will use the most, and give the control enough range to cover any fine-tuning.

If you are using one mini-switch per pickup, I would use the extra pole to switch a resistor to give an effective 250K volume pot (with a 500K volume). You need to wire the two switches as an 'either/or' combination so the same resistor is added when either pickup is split, not with two resistors.

If this all sounds like Chinese I'll see if I can draw it out for you later!

In the mean time I would get two 500K log pots, two mini-switches, a .022uF cap (unless you want a really deep single-coil tone with it rolled off, in which case .047) and a 470K resistor.

tabbycat

ICBM said:

tabbycat said:

do i need a separate cap for the 7k single coil and the 14.5k double coil of each humbucker is what i'm stuck on.

No, one is fine. It *is* possible to use extra switching to do things like cap values and pot resistance, but it gets very complicated and the benefits are fairly marginal unless you're very fussy. Of the two the volume pot value is more important.

For the tone control it's usually best just to choose the values that work best for the sound you will use the most, and give the control enough range to cover any fine-tuning.

If you are using one mini-switch per pickup, I would use the extra pole to switch a resistor to give an effective 250K volume pot (with a 500K volume). You need to wire the two switches as an 'either/or' combination so the same resistor is added when either pickup is split, not with two resistors.

If this all sounds like Chinese I'll see if I can draw it out for you later!

In the mean time I would get two 500K log pots, two mini-switches, a .022uF cap (unless you want a really deep single-coil tone with it rolled off, in which case .047) and a 470K resistor.

hey @ICBM thanks for the clarification (though it may take a while to sink in).

i don't want to hijack jaffa's thread but it sounds as if we are trying to do the same thing, so hopefully this will apply to us both.

all the bits i have if the switches are dpdt on-on, if they are on-on-on i will raid something or get some in. i only want single/double not phase, etc. have 1/4w mf resistors and cc which may be rated higher.

cap thing i agree re kiss. i tried a blues hawk with multiple tone stacks on a rotary switch recently that was interesting. didn't rate the guitar but the switch was cool. but less to go wrong best for guitar onboard controls.

have got a weird brown square 01/400 cap on the tone atm (c1971 with the guitar i think). not seen before. but will reuse as works perfectly with the (unsplit but split-able) hums it is attached to.

thanks for the offer of the diagram. it's generous of you (and tempting). i don't want to be a lazy b so will try and work something out first and pm you for approval or suggestions. long overdue learning. am sure i understand the tech but lack the confidence.

the_jaffa

Don't worry at all about hijacking my thread, it's all great info so all beneficial.