Looking For 2 Different Wiring Schematics

[wwwdotcomdotnet]

I am looking for an EASY TO READ schematic of:

-1 humbucker with 1 volume and 1 tone pot

-2 humbuckers each controlled by 1 volume and 1 tone pot, with a three way toggle switch.

*I want to wire a kill switch for both also

reason is i am in the process of building two guitars

also, what resistances am i looking for in the pots (i want to use the same specs from my gibson sg) and what capacitances am i looking for in the capacitors?

any help would be great.

[Primal]

Seymour Duncan's website has some excellent diagrams.

[wwwdotcomdotnet]

Seymour Duncan's website has some excellent diagrams.

wow, those are perfect

thanks

[wwwdotcomdotnet]

also, what resistances am i looking for in the pots (i want to use the same specs from my gibson sg) and what capacitances am i looking for in the capacitors?

anyone?

[Robert_the_damned]

You pots should be 500Kohm pots (which is the norm for humbuckers). I think Gibson would probably be using .022uF capacitors as standard.

[wwwdotcomdotnet]

You pots should be 500Kohm pots (which is the norm for humbuckers). I think Gibson would probably be using .022uF capacitors as standard.

should the pots be 500k for both the volume and tone?

[al heeley]

yep, both 500k, normal convention though is 500k log (A) for the tones and 500k linear ( for the volumes.

Someone please tell me if I have the A and B the wrong way round!

Also cap values: 0.022uf or 0.047uF caps are common in HB guitars.

[another doug]

It says on the SD diagrams - 500K for all the pots, and they had.047 caps in the ones I looked at.

edit: Al beat me to it!

Edited November 6, 2006 by another doug

[unklmickey]

...(i want to use the same specs from my gibson sg) and what capacitances am i looking for in the capacitors?...

Robert has the right info for values on this.... 0.02uF is standard fare for most all Gibson tone controls. 500k pots.

Al, that's correct on the Tone pots... (A) log taper....A is for Audio, (at least this is true for the past couple of decades.)

usually linear taper for the volumes, but on a few models they use audio taper instead.

Gibson has a few (hard to read) diagrams on their site.

http://www.gibson.com/Service/Tech/Schematics/

the final piece of the puzzle: wire the volume controls "normal" or 'backward' (independent) ?

both styles were seen, at different times, on the SG.

[Primal]

yep, both 500k, normal convention though is 500k log (A) for the tones and 500k linear ( for the volumes.

Someone please tell me if I have the A and B the wrong way round!

Also cap values: 0.022uf or 0.047uF caps are common in HB guitars.

You do have 'em backwards. Volume pots should be logarithmic (aka audio taper), while the tone should be linear (or even audio tapers... the pots on my Epi LP seem to be identical).

[unklmickey]

hi Primal,

i don't think Gibson ever used linear taper pots for the tone controls.

BTW, i DO like your middle name.

unk

[al heeley]

My Epi dot has log (A) pots for tone and linear( for volume. It's a matter of taste isn't it? The argument I heard is that not many people bother using tone settings between 0 and 6, most of the adjustment will be in the 6-10 range so a log pot is better for that spread.

BTW, Unkl is god on the guitarnuts forum, anything to do with electronics, never met a more knowldgeable or helpful person, a pleaseure to see you post here.

Al (aka Flat Eric)

[Primal]

Your Epi has a linear for volume? Thats odd, because the human ear hears volume in a logarithmic way (take a look at the decibel system). Therefore, using a linear pot for volume will give you a perceived volume change that is greater in the lower end and seems to increase in volume less quickly as the volume knob is rolled up, hence why there is such a thing as an audio taper pot, to make the change in volume more even to our ears.

[al heeley]

Thats what I always thought too, it made sense in physics classes but I guess it doesn't hold true for guitar resistance, maybe it makes sense for amplifier volumes, decibels are a log scale.

If vol changes less quickly at 7-10 and faster at 0-3 for example, then it is easier to back off the vol a bit when its up at 'normal' settings, ie: more accurate. Normal settings for me would be the 7-10 range, so I guess a log pot might be better. I don't think either is wrong, just reporting what others have told me and what is fitted to my HB guitars.

[unklmickey]

thanks for the kind, welcoming words, Al.

before anyone accuses you of sacrilege:

...Unkl is god on the guitarnuts forum...

i want to point out the 'god' thing is a rank -- related to post count.

and that's just what's built in to the BB system they are using. i don't have a choice of what the rank is called.

Al, there's something to be said about personal taste, but in this case, i was taking wwwdotcomdotnet's original post verbatim:

...(i want to use the same specs from my gibson sg) ...

so going by that, definitely audio taper pots for the tone controls, and probably linears for the volumes.

Primal,

what you've said seems very logical.

any time you are using a single volume control, audio taper pots are a much better choice.

but, there is one more bit of information that will help in understanding why Gibson uses linear pots for volume.

in guitars with separate volume controls for each pickup, when BOTH pickups are on, the resistance that is introduced when one control is turned down a little is in series with the output.

since the other pickup is in parallel with the output, this creates a voltage divider.

with a moderate amount of resistance (about 21~22k) introduced by the volume control (from the high terminal to the wiper), and 10k for the pickups, that will make the contribution of the reduced volume pickup about half of what the other pickup contributes. even with a 500k linear, that's still pretty high on the dial.

with a log taper pot, that becomes very hard to dial in.

so it's all about mixing the pickups when they are used together.

and you're right, linears aren't nearly as good for controlling overall volume.

hope this helps,

unk

[wwwdotcomdotnet]

thanks for all the info guys

[Primal]

Thanks for the clarification unk. Makes perfect sense now that I think about it. I probably didn't think about it much because I've dissected the neck pickup in my Epi LP and turned it into a sustainer driver, thus I don't have the problem of the two pots creating a voltage divider because I'm only using a single pot (maybe I should replace it with an audio taper pot... I've been meaning to get a 1meg pot).

[unklmickey]

hi Primal,

it's not so much the 2 pots making a voltage divider, it's the internal resistance of the pickup that's at max volume that makes the lower portion of the divider,

and the resistance (from high terminal to wiper) of the turned down pot, that makes the upper portion.

you probably will like a log taper better for a single control. it will act more like what one expects of a volume control.

i have a chinese Epiphone LPjr that came with a linear for a volume control.

don't ask me WHY they would put one in a single pickup guitar.

it is kinda nice, if you want to 'just take the edge off', but gets sorta stupid when you try to turn the volume seriously down.

[Primal]

Yea, I'm no electronics expert, but I'm assuming you were talking about how LPs are wired so that the two volume pots interact with each other. Anyway, the answer as to why your LP jr came with a linear pot is simple: Epis are the low budget guitars, and as such Gibson doesn't feel the need to differentiate between the models. Why order log pots for their one line of LP jrs when they can just grab out of the factory parts bin?