Results 1 to 17 of 17

Thread: Four pickup wiring - with phase switch

  1. #1
    Junior Member
    Join Date
    Apr 2019
    Posts
    12
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    0

    Four pickup wiring - with phase switch

    I have a set of pickups, switches and pots from a mid sixties Italian -- probably a Galanti or Eko. There are four pickups, and they are all on a board with a circuit built in, two pickups above the circuit, two below it, so, PUs 1&@ above, 3&4 below. The switching is awesome, six positions -- all four pickups, no pickups,one, 1 by itself, 4 by itself, 1+4, or 2+3. https://link.shutterfly.com/ePOtUkVYlX

    As the picks show, it looks like someone divided the leads from the pickups, wired the top two and bottom two so they could then pass through the circuit board, and then the individual pickup signals go out to the switch mechanism.

    Because I don't know what the original wiring looked like, and because I have heard that lots of people thought the circuit was not very good, and because I have read that the Galanti Grand Prix 4V was meant to be played with pups out of phase . . . I am considering rewiring all this, so that I can have 1+4 in or out of phase, and 2+3 in or out of phase, and put a cap/resistor pair for treble bleed at the tone pot. I want just single tone and volume, so I can use the pickguard that I had copied from the original.

    My question is -- what does this wiring look like -- should I run from the pickups to a phase switch to the pickup switch? With a simple phase switch, I could run PU 1 and PU 3 to the phase switch, so that the polarity of the signal is reversed when it hits the pickup selector switch . . . and from there is goes to tone, vol and out.

    FYI -- I am in Providence, Rhode Island, USA

    TIA

    Ari Gabinet

    If this works, I could, in theory, run both phase controlled pickups to the same, single phase switch, right? And that way I could even have all four pickups selected with the pairs in phase or out of phase. Two phase switches would give me more options . . .

    I am not an expert in this area, so I am looking for help and advice. I a building a reproduction of a Galanti Grand Prix around these controls . . .

    Any help much appreciated.

    0 Not allowed! Not allowed!

  2. #2
    Supporting Member
    Join Date
    Nov 2016
    Location
    Nova Scotia
    Posts
    159
    Thumbs Up/Down
    Received: 70/1
    Given: 160/1
    Rep Power
    3
    This seems like a good time to speak in praise of the Mustang switching arrangement where each pickup has a 3-position slide switch that allows each pickup to be switched off or on in either phase. Dead simple and really effective. I think what you were describing could be done, but it would be complicated and less versatile. I just saw that you are planning on using the original controls so that may limit the options somewhat.

    1 Not allowed! Not allowed!

  3. #3
    Junior Member
    Join Date
    Apr 2019
    Posts
    12
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    0
    Thanks, I want to use the accordion switches that were original -- but that is just pickup selection, I will be adding switches -- at least one . . . but is my concept correct, that I have to wire the phase switch between the pickup and the selector switch? It won't do my much good to put the phase switch at the volume or tone pot (push pull) since I have this bizarre set of selector switches.

    TIA

    0 Not allowed! Not allowed!

  4. #4
    ToneOholic! big_teee's Avatar
    Join Date
    Jun 2010
    Location
    Mid-South USA
    Posts
    11,190
    Thumbs Up/Down
    Received: 752/32
    Given: 743/14
    Rep Power
    21
    I was also thinking of the Brian May guitar wiring.
    Each of the 3 pickups have an on off, and each pickup has its own reverse polarity.
    You can get any combo, you could do that with a 4 pickup, by using eight switches.
    T
    Click image for larger version. 

Name:	Oct14_PG_CLM_ModGarage_image1_WEB.jpg 
Views:	8 
Size:	48.4 KB 
ID:	53902

    0 Not allowed! Not allowed!
    Courage is being Scared to Death, but Saddling up anyway! (John Wayne)

    Terry

  5. #5
    Junior Member
    Join Date
    Apr 2019
    Posts
    12
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    0

    Thumbs up

    Quote Originally Posted by big_teee View Post
    I was also thinking of the Brian May guitar wiring.
    Each of the 3 pickups have an on off, and each pickup has its own reverse polarity.
    You can get any combo, you could do that with a 4 pickup, by using eight switches.
    T
    Click image for larger version. 

Name:	Oct14_PG_CLM_ModGarage_image1_WEB.jpg 
Views:	8 
Size:	48.4 KB 
ID:	53902
    Love that brian may setup. But I already have SIX selector switches! and since only one PUP out of each paid needs to be out of phase, I could do Phase switches for 1 & 3 and I would have all my combinations available through the selector (1/4 and 2/3) covered. I just want to confirm that the pickup signal should go first to the phase switch, then to the selector switch . . .

    0 Not allowed! Not allowed!

  6. #6
    ToneOholic! big_teee's Avatar
    Join Date
    Jun 2010
    Location
    Mid-South USA
    Posts
    11,190
    Thumbs Up/Down
    Received: 752/32
    Given: 743/14
    Rep Power
    21
    We really need a layout, or schematic of your pickups, & switches, before I could confirm anything.
    Can you draw it out on paper and submit it here?
    T

    0 Not allowed! Not allowed!
    Courage is being Scared to Death, but Saddling up anyway! (John Wayne)

    Terry

  7. #7
    Junior Member
    Join Date
    Apr 2019
    Posts
    12
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    0
    Quote Originally Posted by big_teee View Post
    We really need a layout, or schematic of your pickups, & switches, before I could confirm anything.
    Can you draw it out on paper and submit it here?
    T
    https://link.shutterfly.com/W8fnlQqcoX

    Sorry I can't seem to upload the pics directly. I'm pretty much a beginner with wiring.

    0 Not allowed! Not allowed!

  8. #8
    ToneOholic! big_teee's Avatar
    Join Date
    Jun 2010
    Location
    Mid-South USA
    Posts
    11,190
    Thumbs Up/Down
    Received: 752/32
    Given: 743/14
    Rep Power
    21
    I think the phase switching will work.
    Don't have a clue how the 1&4, 2&3 magic works.
    I think you will have to do a lot of trial and error wiring, and testing.
    When I wire something exotic, I do lots of simulating, switching, checking continuity with a ohm meter, for the load, in place of the pickups.
    Give it a try, and please keep us posted with your outcome!
    Then

    0 Not allowed! Not allowed!
    Courage is being Scared to Death, but Saddling up anyway! (John Wayne)

    Terry

  9. #9
    Member
    Join Date
    Dec 2013
    Posts
    216
    Thumbs Up/Down
    Received: 35/0
    Given: 10/0
    Rep Power
    6
    You could run test leads out and try all of this outside the guitar before you commit to anything.

    With 6 switches you could wire each pup to a switch and have 2 left for phase switching.

    I don't know how important the original board is to you.

    0 Not allowed! Not allowed!

  10. #10
    Junior Member
    Join Date
    Apr 2019
    Posts
    12
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    0
    Quote Originally Posted by ric View Post
    You could run test leads out and try all of this outside the guitar before you commit to anything.

    With 6 switches you could wire each pup to a switch and have 2 left for phase switching.

    I don't know how important the original board is to you.
    👍 Got the multimeter out.

    0 Not allowed! Not allowed!

  11. #11
    Junior Member
    Join Date
    Apr 2019
    Posts
    12
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    0
    https://link.shutterfly.com/wQTX8l1NpX

    The six way switch works, there is a selector button for "0" -- no sound, But this selection actually creates a contact with a lead coming from the circuit board. This leads me to conclude that the circuit board has a muting function built in? There are six possible selections from the switch, and four leads coming from the circuit to the switch, only one lead coming out of the switch. The available selections are:

    All
    1 (switch creates a contact between the output lug and one input lug)
    4 (switch creates a contact between the output lug and a different input lug)
    1+4 (Switch creates contact between output lug and the 1 input and the 4 input lugs)
    2+3 (switch creates contact between output lug and yet another input lug)
    Mute (Switch creates contact between output lug and the fourth input lug)

    The four leads coming out of the circuit and connecting to the input lugs in the switch, therefore, must be

    1
    4
    2+3
    Mute

    There is a bunch of wire splicing from the pickups -- essentially wiring 1+2 together and wiring 3+4 together. It is NOT factory original. This leads me to conclude that someone tried to pair the pickups to make a sort of "humbucker by proxy" set up. All I really need to do to get back to original is figure out how to wire the inputs from the pickups. It should actually be pretty easy because there are matching colored wires on the switch input lugs and the circuit outputs . . .

    1 Not allowed! Not allowed!

  12. #12
    Junior Member
    Join Date
    Apr 2019
    Posts
    12
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    0
    Multimeter very helpful today --

    First, I think all the caps are dead.

    Second, I think the circuit board has three circuits in it

    two fairly straightforward cap/resistor in parallel filters, one for 1 & 2 and one for 3& 4 -- both with 1600 mu cap and a resistor whose value is . . . yet to be determined.

    One cap/resistor pair with a different value -- 2200 mu cap and a different resistor --

    This latter cap/resistor pair leads to the "0" switch -- which, I believe, is a mute, but not a silencer, but just a more muffled tone . . .

    So now I think I have to remove the circuit board from the metal plate (it's riveted) and replace the caps.

    0 Not allowed! Not allowed!
    Last edited by agabinet; 06-12-2019 at 12:31 PM.

  13. #13
    Senior Member
    Join Date
    Mar 2018
    Location
    Germany
    Posts
    1,478
    Thumbs Up/Down
    Received: 1,070/1
    Given: 674/2
    Rep Power
    4
    two fairly straightforward cap/resistor in parallel filters, one for 1 & 2 and one for 3& 4 -- both with 1600 mu cap and a resistor whose value is . . . yet to be determined.

    One cap/resistor pair with a different value -- 2200 mu cap and a different resistor --
    Surely not 1600F or 2200F caps. Those would be useless in guitar. I suppose they are 1600p(pico)F and 2200pF (pictures of the markings would help) and I doubt that they are defective. The 3 caps in your pictures look like good quality "Styroflex" (polystyrene) caps.

    1 Not allowed! Not allowed!
    Last edited by Helmholtz; 06-12-2019 at 01:13 PM.
    - Own Opinions Only -

  14. #14
    Junior Member
    Join Date
    Apr 2019
    Posts
    12
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    0
    Quote Originally Posted by Helmholtz View Post
    Surely not 1600F or 2200F caps. Those would be useless in guitar. I suppose they are 1600p(pico)F and 2200pF (pictures of the markings would help) and I doubt that they are defective. The 3 caps in your pictures look like good quality "Styroflex" (polystyrene) caps.
    You are correct, shows you how little knowledge I have. The caps say "1600 pF/5% 250V" and "2200 pF/5% 125V"

    But I don't get any movement of the needle of my meter when I test them. I set the ohm meter at 10K . . . and get no movement.

    0 Not allowed! Not allowed!

  15. #15
    Senior Member
    Join Date
    Mar 2018
    Location
    Germany
    Posts
    1,478
    Thumbs Up/Down
    Received: 1,070/1
    Given: 674/2
    Rep Power
    4
    But I don't get any movement of the needle of my meter when I test them. I set the ohm meter at 10K . . . and get no movement.
    You can't measure capacitance with an ohmmeter. A good cap should show infinite resistance. As said I would assume them to be fine. Just be careful/quick when soldering. Polystyrene can't stand much temperature (70C max.).

    0 Not allowed! Not allowed!
    Last edited by Helmholtz; 06-12-2019 at 04:02 PM.
    - Own Opinions Only -

  16. #16
    Junior Member
    Join Date
    Apr 2019
    Posts
    12
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    0
    Quote Originally Posted by Helmholtz View Post
    You can't measure capacitance with an ohmmeter. A good cap should show infinite resistance. As said I would assume them to be fine. Just be careful/quick when soldering. Polystyrene can't stand much temperature (70C max.).
    I took the circuit board off the plate. Here are pics. It's clear that there are three cap/resistor circuits. The one with the 2200 pf cap is the "mute" setting . . . https://link.shutterfly.com/Wv25r0IKsX

    0 Not allowed! Not allowed!

  17. #17
    Senior Member
    Join Date
    Mar 2018
    Location
    Germany
    Posts
    1,478
    Thumbs Up/Down
    Received: 1,070/1
    Given: 674/2
    Rep Power
    4
    Do you know if all PUs are working? What is their resistance (DCR). Do you have a guitar to test the PUs (without any circuit connected)? Maybe just one after the other. The way they sound by themselves may help to decide for a suitable wiring.

    0 Not allowed! Not allowed!
    - Own Opinions Only -

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Coil split and phase wiring
    By Bew316 in forum Guitar Tech
    Replies: 1
    Last Post: 05-19-2019, 03:34 PM
  2. Out of phase switch
    By Bew316 in forum Guitar Tech
    Replies: 4
    Last Post: 05-14-2019, 09:47 PM
  3. Replies: 2
    Last Post: 03-08-2012, 10:35 PM
  4. Wiring '60 ES-330 out of phase?
    By Bluefinger in forum Guitar Tech
    Replies: 10
    Last Post: 02-04-2011, 08:05 PM
  5. Switch for Dunlop Phase 90
    By tubetonez in forum Guitar Effects
    Replies: 2
    Last Post: 09-20-2007, 10:16 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •