SG Junior Pots and Caps?

asdaven

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What kinds of Pots and Caps do you run on a SG JR style guitar with a P90? I have a SG JR knockoff (Harley Benton) in the process of upgrading parts. I shimmed up the stock pickup for now which greatly improved it. But im just wondering on a SG JR style guitar whether its Gibson, Epiphone, etc, which pot and cap values are you running? It came with two 500K pots.

Its a little bright. I tried switching to a 250K tone pot leaving the volume 500K but feel it took away some from the sound (also running 50s Gibson Wiring). It also increased the interaction between the volume and tone with the 50s wiring and felt the volume wasnt as high with the 250K tone pot. Also it got muddy too quick even trying a .015uf capacitor in this setup. So im back to the 500K tone pot. Debating between going with a .047uf cap being a 500K pot or .033uf. I know .022uf is the common spec on this type of guitar. But thats also originally with the 250K tone pot...at least for the LP Jr. The SG Jr is a brighter guitar. Thinking .033uf with the 500K pot might be a good compromise here.

Also, can anybody reccomend a good wraparound bridge unit that wont break the bank with locking studs and brass saddles? I bought a cheap Wilkinson Amazon bridge which if I could upgrade the studs and screws to steel or aluminum and change out the saddles to something better than zinc preferably brass...it probably would work good. Ive looked at the Gotoh unit but again zinc saddles and I think its an ugly looking wraparound bridge.
 

asdaven

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I shimmed the pickup higher with my thickest shim and its pretty close to the strings now and theres actually more bass now and less icepick, which is contrary to what usally happens with pickups where you want to move it further away if theres icepick. But maybe the P90 is different. And man its a cheap weak pickup, but shimming it has brought it alive. Was already looking for a upgraded pickup but might play as is for now.

I switched back to a .033 uf capacitor...like that with the 500K dual pots in this setup the best I think. Just a slightly more aggressive taper than a .022uf. I almost never use .047uf caps in any of my guitars even my strat.
 

Decadent Dan

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I shimmed the pickup higher with my thickest shim and its pretty close to the strings now and theres actually more bass now and less icepick, which is contrary to what usally happens with pickups where you want to move it further away if theres icepick. But maybe the P90 is different. And man its a cheap weak pickup, but shimming it has brought it alive. Was already looking for a upgraded pickup but might play as is for now.

I switched back to a .033 uf capacitor...like that with the 500K dual pots in this setup the best I think. Just a slightly more aggressive taper than a .022uf. I almost never use .047uf caps in any of my guitars even my strat.
Specs online say 7.1k for that one. Gibsons are usually around 8k.
 

fernieite

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The original electronics in my 1963 Les Paul Junior are 2 x 500k pots (centralab) and a .022 ceramic cap. Sounds great with this combo!
Maybe give it a try?
 

plankton

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I like 500K pots with my P90 guitars. I think I've got a 22nF cap in mine, but I have used other values before. Maybe try a couple out ans see what you prefer.

Can't help you with a bridge, I prefer the lightning bolt ones.
 

asdaven

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I switched to a .022 Orange Drop cap. I like it. Oddly more bass with a lower value cap. Odd.

Even though its "simplier" , ive never had a one pickup guitar before. Which means the only way to shape the sound is with the tone control since theres no other pickups or pickup combinations.

I also wired it up "50s Style". Makes sense on my Les Paul. Works good on my Telecaster. But debating switching back to normal wiring since it darkens up when you turn the volume down. Also with 50s style wiring, it reduces the volume when you turn down the tone pot. Which on a Junior style guitars, your going to be using that tone adjustment much more than other guitars to shape the sound.

So I havent decided if the 50s wiring is a good thing in this application or not.
 

smitty_p

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I switched to a .022 Orange Drop cap. I like it. Oddly more bass with a lower value cap. Odd.

Even though its "simplier" , ive never had a one pickup guitar before. Which means the only way to shape the sound is with the tone control since theres no other pickups or pickup combinations.

I also wired it up "50s Style". Makes sense on my Les Paul. Works good on my Telecaster. But debating switching back to normal wiring since it darkens up when you turn the volume down. Also with 50s style wiring, it reduces the volume when you turn down the tone pot. Which on a Junior style guitars, your going to be using that tone adjustment much more than other guitars to shape the sound.

So I havent decided if the 50s wiring is a good thing in this application or not.

I used '50s wiring on my guitars for awhile, then went back to the stock, modern wiring. Whatever benefits the '50s wiring may have afforded to me were more than negated, for my purposes, by the quirky behavior that you've mentioned.
 

plankton

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If you don't like the loss in high end when you roll down the volume try a treble bleed circuit. I found for me it was much better than 50's wiring. I prefer the Kinman style which has a cap and resistor in series.
 

asdaven

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If you don't like the loss in high end when you roll down the volume try a treble bleed circuit. I found for me it was much better than 50's wiring. I prefer the Kinman style which has a cap and resistor in series.
Not a fan of Treble Bleed but only tried the parallel style . Curious about the Kinman mod. What values do you use?

To me 50s wiring just splits the difference. Modern wiring has the quirkyness on the volume knob with it darkening 50s wiring makes the quirky on the tone knob.
 

plankton

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Not a fan of Treble Bleed but only tried the parallel style . Curious about the Kinman mod. What values do you use?

To me 50s wiring just splits the difference. Modern wiring has the quirkyness on the volume knob with it darkening 50s wiring makes the quirky on the tone knob.

With a 500k pot I start with a 1.2nF cap and a 220k resistor. With a 250k pot I switch to a 130k resistor. I might play around with the resistor values to tweak the circuit to suit.

The parallel setup messes up the taper of the volume pot but in series it's fine.
What does wiring the cap to the wiper of the tone pot do?

Electronically, nothing.
 

Decadent Dan

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Looks like they did the same for the ‘19 Standard 61..
F13BDABF-8C85-4FEE-BA65-C057B77C8E29.jpeg
 

plankton

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It always looks weird when they put those big, high voltage caps in a guitar.

As for the placement of the cap in a guitar tone circuit:

tone pot connections.png

This was borrowed from a post on TDPRI.
 

Decadent Dan

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It always looks weird when they put those big, high voltage caps in a guitar.

As for the placement of the cap in a guitar tone circuit:

View attachment 49706

This was borrowed from a post on TDPRI.
I thought the same thing about the orange drops in a Gibson. They used to be synonymous with Fender amps but now they’re marketed as some trendy vintage thing for guitars.
 

asdaven

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It always looks weird when they put those big, high voltage caps in a guitar.

As for the placement of the cap in a guitar tone circuit:

View attachment 49706

This was borrowed from a post on TDPRI.
So wiring the cap to the inner lug or the outer lug dosent reverse the taper of the tone pot?

Perhaps wiring the middle lug to the cap and ground is better because it helps ground out the unused lug to reduce noise in the signal. I read that somewhere.

Ive gone back to 50s wiring. Tried the series (kinman) treble bleed ....ALOT better than the parallel ones ive tried in the past but the 50s wiring just makes the guitar sound better. Just gotta deal with the volume tone knob interaction.
 

plankton

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So wiring the cap to the inner lug or the outer lug dosent reverse the taper of the tone pot?

Perhaps wiring the middle lug to the cap and ground is better because it helps ground out the unused lug to reduce noise in the signal. I read that somewhere.

Ive gone back to 50s wiring. Tried the series (kinman) treble bleed ....ALOT better than the parallel ones ive tried in the past but the 50s wiring just makes the guitar sound better. Just gotta deal with the volume tone knob interaction.

If you grounded the opposite outside lug of a pot and attached the signal wire to either of the other terminals it would reverse the operation of the pot, but all of the variations shown in the graphic I shared are electronically the same.
 

asdaven

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I typically dont wire the capacitor between the pots. Usually center lug or outer lug then to the back of the pot...then a wire across.

On my other guitar that is volume and tone like this...I accidentally grounded the wrong outer lug of the volume pot. The tone pot operated backwards when wired as normal. I reversed the tone pot wiring and it works normal. Volume works in the right direction as well.
 


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