3 PU + 5 Pots + 2 3 way switches

[sadfuzz]

Hi All, 

I recently picked up a Gretsch 2627T Streamliner with absolutely zero electronics for $80 

I have a some pickups and pots, switches, and wire from left over projects so I thought I'd slap something together on the very cheap. I emailed Gretsch but they don't have a wiring schematic for this model as it seems it was a Guitar Center special edition. I have attached the Control functions for reference but that doesn't load correctly it works as follows:

3 way switch 1 - Neck / Neck + Bridge / Bridge 

3 Way Switch 2 - Middle Pick up  Isolated / On /Off

1 Master Volume

3 Pick up Volume

1 Master Tone


What I have to put in it: 

Bridge + Neck GFS Mean 90's ( Humbucker sized P90's 2 wire + ground) 8.7K & 7.9K

Bridge GFS PAF Humbuckers ( 4 wire + ground) 8.1K  

Was thinking about wiring it the same as stock using Mean 90's Bridge and Neck and PAF in the middle with a push pull pot for a coil split.

Only other thing I was considering was replacing the Master volume with something else maybe a 3 way tone switch like on a vintage Gretsch. 

Anyway I can definitely solder and hook it all up I just don't know enough to make the schematic. Can someone help lay that out? I'm also up for suggestions for wiring if someone thinks there's a better use of holes?

thanks,
-Trey

[newey]

sadfuzz-

Hello and Welcome to G-Nutz2!

First question is, you mentioned the pickups you have but didn't mention the switches you have. Are the original switches with the guitar?

The reason I ask is that I can't see how to do a Middle pickup switch that isolates the middle pickup using a regular 3-way toggle switch. Maybe it's possible with a single-pole switch and I'm just not clever enough to see the solution. But I suspect the original switch to do this would have to have been a 2-pole switch, a DPDT On-On-On switch. A DPDT On-Off-On could also be used, but the "off" position would have to be in the center, which isn't what the diagram shows.

If you haven't bought switches yet, a regular 3-way toggle plus a DPDT On-On-On toggle would do the trick.

If you want to do the Gretsch tone switch thing, they do have a diagram of that on the Gretsch website support page that you can copy.

Just by way of concept here, in doing a diagram, each pickup will be firsat wired to its individual volume pot. N and B pickups then go to the 3-way pickup selector, while the neck pickup goes to its 3-way switch DPDT as discussed above). Outputs from both switches go to the Master V pot, and from there to the output jack. The Master tone is then wired off of the master volume pot, same as with any 2-pot V + T guitar,

Adding a push/pull to split the middle pickup is easy enough to incorporate. It would go between the middle pickup and the 3-way "iso" switch. Logically, you'd replace the middle pickup volume with the push/pull.

[sadfuzz]

Hey Newey thanks for all the info

I have 2 switchcraft standard 3 way switches so on-on-on (which looks like what was there originally)

I found a picture from someone selling an original harness online though I cant really see how they wired the 3 way's 


Once I figure out the switches Ill be able to wire the guitar up 

[newey]

I'm only seeing 2 pickups in that picture. Gretsch made several version of the Streamliner, I'm not sure that's the one you have. But it does have 5 pots, which would be odd for a two-pickup guitar. In any event, as you note, we can't see the wiring to the three-way switches.

But now that I look at this, I think I see how it could be done with just a SPDT switch. Must have been half asleep last night when I said it couldn't be done!

Like this:



This is of course a highly stylized picture of the actual 3-way switches but you get the idea, I'm sure. From here, it's probably best if you draw up a complete diagram so we can double-check everything before you dive into it.

[sadfuzz]

Thanks so much for that

I've attached a schematic of what I think will work, I didn't include grounds or the push pull pot as that seems pretty straight forward. Let me know what you think 

[JohnH]

The Gretsch diagram reminds me of my friends 6120. That's an HH 'Brian Setzer' style. It had some features in common with yours, particularly the use of both individual and master volumes. He had typical Gretch pickups, either Filtertron or TV Jones.

It sounded fantastic for the music it was designed for, and he could nail the Rockabilly sound. But for anything else it had a tendency to sound a bit muted.

The reasons were a few things, including the double volume controls combined with tone controls adding more load, and the size of it needing long lengths of internal wiring. I helped investigate, and we tried a few things. He didn't want to mod the guitar, but just understand how to work it best. We did some external resistance measurements and tried different cables including an active buffer cable. The best answer for him was a high quality short (10') cord from guitar to his pedal-processor, at which point the signal was buffered and became robust enough to drive a longer cable back to his amp.

This Premier Guitar article is mostly good info:

www.premierguitar.com/diy/mod-garage/gretsch-guitar-wiring

So for you, the existence of five pots causes risks to your tone unless they are well considered! Your pickups may tend to a darker heavier tone than most Gretches, and I expect you'll want to keep control to take particular care of the high end tones.

Things that could help (id suggest several of these measures):

Use a low capacitance shielded wire for internal connections

Use no-load tone pots

Treble bleed on volume pots

500k pots

Consider if you really want both the master volume and the individual volumes? If not, could maybe repurpose one or two.

These things could be brought into the design while also considering switching and how best to engage the three pickups.

It'll be a great guitar!

[sadfuzz]

That’s a good read,

I’ll have to measure the capacitance of my normal pushback cloth wiring and see if it’s worth getting the cable mentioned in the article.

I was thinking about getting rid of the master volume, any have a suggestion for what to do with the hole? The guitar has a pot sized hole so definitely need to do something with it

[JohnH]

Nov 23, 2024 14:41:26 GMT -5 sadfuzz said:

I was thinking about getting rid of the master volume, any have a suggestion for what to do with the hole? The guitar has a pot sized hole so definitely need to do something with it

Its a good questions, heres my thoughts, with 5 pot-sized holes and a wish for a dedicated pot for each pickup:

1. The two toggles will let you select any single or parallel combo of pickups, they'd be traditional 'Gibson-style' on-on-on guitar toggles, and there'd be a few options, but id expect as per your thinking, Toggle 1 does:

N,
N+B,
B

and Toggle 2 does:

whatever Toggle 1 is set to,
Toggle 1 plus M,
M alone

In thinking about that, what would be the most common switch moves that you might want to make with just one quick toggle flick while playing? eg, with this scenariao, you could quickly swipe from a thick snarly P90 tone, to a clear crisp single-coil tone on the M pickup.

2. With five holes, which are the best for placing your three volumes? for playing and for wiring?. Is it per the diagram?, or might the old MV knob be good as the neck volume? etc

3. Hard-wire the volume pots directly after the pickups, before the switching so that when you de-select a pickup, its pot is also out of circuit (ie like LP wiring on an HH)

4. Whichever is the M volume, is also a push-pull to coil-cut the M.

5. All volumes have treble bleed (unless you prefer without).

6. Tone and the use of the fifth hole: This is where it could potentially get awesome if combined with 1 to 5 above...

You can use a tone pot and a standard rotary switch with up to 12 positions. You could have a full varitone-like sweep of caps ranging from very small, to big to let you shape all of your frequencies. You could have 12 different cap values to sweep across, or you could have some that direct the tone shaping pot to go after the volumes as a Master Tone, and some to make it go specifically to a particular pickup for when you use that alone. All could be under control of the tone pot, or some could be without the tone pot, particularly for the smaller caps. This switch could also include the setting for no-load, or you could use a no-load pot with it. All quite simple actually.

[sadfuzz]

Oh nice the Varitone is a good idea, Ill have to post a video when I have it all together. 

I'm essentially making a ES 355 with a 3rd pickup 

[JohnH]

OK great, If youd like, Id be happy to work out a suggestion for caps and how they could be wired in with the tone pot and switch?