p-rails wiring advice

RMorgan

New member
Hey folks,

Well, I'm setting up an SG Junior type guitar and I'm equipping it with a p-rail and two push/pull pots, so I can use all possible combinations.

I've found this wiring schematic here, but since I'm a noob regarding this sort of stuff, I'd appreciate if anyone could confirm if it is correct:

P-Rail,_1_volume,_1_tone,_2_p-p.jpg

Also, I'm interested to know of any possible variations of this scheme that could possibly cause positive tonal results.

Thanks in advance,

R.
 
Re: p-rails wiring advice

Diagram by Hermetico, one of the most respected wiring gurus on this board. You can trust it.
 
Re: p-rails wiring advice

Diagram by Hermetico, one of the most respected wiring gurus on this board. You can trust it.

A very trustworthy member of another forum told me it's wrong, so now I'm really confused. :omg:

Here's what he said:

The colors aren't right, for starters - the red and white SHOULD be the series pair. Black should always go to hot, not switched; green should always go to ground, not switched.

I'll take a swing at it... Here's my edit of the S-D drawing. With no pulls, the coils are in series...

p-rails-v-t-pp.jpg

What do you think?

R.
 
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Re: p-rails wiring advice

About splitting humbuckers: I wired my JB series/split/parallel and parallel sounds louder than series and split. Series and split sound about the same volume. I checked and rechecked my wiring. Series and split sound good not all thin like a bad ground connection or something, it's just parallel's volume sounds boosted. Is this normal?
 
Re: p-rails wiring advice

Do you have a meter to test what the readings are? Can you wire it directly to the jack to confirm both coils are working as they are supposed to? Parallel shouldn't really sound louder than split- if anything the same. And both should be quieter than series. Tap on the poles with a screwdriver to confirm both coils are working in series and parallel, and one coil in split.
 
Re: p-rails wiring advice

Thanx for the advice Mincer. Everything sounds right when I tap on the poles, both sides sound for series and parallel and only the slug side with split. But when I play, series and split are quieter than parallel. It's a weird one. I'll score a meter tomorrow. The only thing I can think of is I damaged the dpdt switch while soldering and resoldering trying to get it right. I don't think the pickup is damaged. We shall see.
 
Re: p-rails wiring advice

A very trustworthy member of another forum told me it's wrong, so now I'm really confused. :omg:

Here's what he said:



What do you think?

R.

Uhhh... the red and white ARE the series pair in your original diagram, the black IS always connected to hot and the green IS always connected to ground. Tell your "trustworthy member of another forum" to look again!

(Admittedly however, this other person would have had to have made a little bit of a leap of logic as the "white" is represented by a light blue... an unfortunate but necessary concession when working with a white background. Perhaps that's where he became confused.)


Sent from my iPhone using Tapatalk
 
Re: p-rails wiring advice

I was confusing series with parallel like a jackass. Nothing was defective lol. That makes sense that split and parallel would have a lower output than series. About the JB: I moved it from 1 inch away from the saddles (standard on my lp and jag) to 1 3/8 inches away from the saddles and it sounds WAY better. Much more useable and less harsh. But if I pick aggressively I can still get it as bright as I want for my taste. Btw I'm loving the series/split/parallel option for hbs. Way more sounds to fiddle with! Here's the mustang work in progress. I'll buy or make a new pickguard now that I've finalized the pup locations.mustang.jpg
 
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This is a very old post, but I’m curious which of the two wiring diagrams is correct. The second one looks so much simpler, on the first one. It looks like there are a lot of jumper wires. Thank you very much.
 
The first one, by Hermetico, is correct. The 2nd one is wrong. It leaves one coil hanging out on the "hot" side of the circuit, acting as a noise antenna, when it isn't selected. That's why Hermetico included the extra jumpers.

Black is NOT switched. It's hardwired to the output. And green is NOT switched. It's hardwired to ground. That person wasn't analyzing the circuit correctly.
 
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Cool thanks so much for the reply, I’m getting ready to install on my electric banjo. I wish I could figure out how to install a bridge pickup but there’s no room under the head- I have some extra heads for this goldtone EB=5 so maybe I’ll try cutting a hole in the head and putting a block underneath the bridge, that just came to me ha ha but anyway thanks again.

oh, one question, where it shows C1 and C2 connected on each pot, does that mean a literal jumper wire or is that just illustrating that those two pins are connected internally?

. Thanks again.
 
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The two reds on VS and the two blues on TS need an external jumper. Good luck with putting this in a banjo. Show pics if you get 'er done.
 
Cool, thanks, I appreciate it.

i’ve been studying pickup wiring this morning and it appears that on this diagram, the tone control is set up like a 50s style, which is cool. (correct me if I’m wrong)

i’m trying to understand how the electric banjo is currently wired from the factory, both wires to the output jack come from the volume pot. I’m thinking of trying the installation with the triple shot first (attached to the factory pot wiring) and then doing the push pull pots later. But I’m wondering what the difference in the tone pot wiring will make.

I think I understand the circuit, but I have not seen another example of it.

Sorry about my pencil on paper diagram.

thanks I enjoy learning about this stuff- I appreciate the help
 

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