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04 December 2012

Wiring Diagram: Hermetico's LP Exchanger mod 2

Classification

Guitar Modded

Gibson Les Paul


Description
  • HH Pickup layout (4 conductors)
  • 1 Swiftcraft 3-way toggle switch
  • 2 volume pots with pull/push
  • 2 tone pots with pull/push

Difficulty Level

Hard

Features

  • Provides standard LP combos, plus a high variety of other combinations.
  • Independent volume and tone for each pickup.
  • Enhanced version of Jimmy Page's wiring design
Wiring Diagram

Click on the diagram for a full sized view.



Comments

Jimmy Page's wiring mod achieves a lot of different combinations but, in my honest opinion, it does it in a way that isn't easy to recall and, some of the combinations produce just silence (the guitar shuts up).
The Exchanger 2 mod is my own take around the Jimmy Page's mod but, making controls easier to map in your mind so, you will be able to easily achieve exactly the combo you were looking for.
 
Each Tone pot splits its corresponding pickup.
Neck Volume puts Neck pickup out-of-phase (changes polarity).
Bridge Volume puts both pickups in series, overwriting the 3 positions of the 3-way (instant booster).
 
But there are some tricks hidden under this design.
Default, NT splits the neck pickup to outer coil but, if you have also BT up, selected coil is inner, instead.
Default, BT splits the bridge pickup to inner coil but, if you have also NT up, selected coil is outer, instead.
Also, the NV (neck volume), when changing the polarity of neck pickup (OOP) is reverting which coil is split by the NT pull/push.
 
In this way, we are achieving one more unique combo than in JP's wiring mod and, the best of all: there is no combo that can accidentally shut up the guitar!.
 
Click on this picture to see a full size of the list of combos:
 
 
In red, unique combos (that appear at least once in that list).
Notice that when the serial switch is up (BV = Bridge Volume), the three positions of the 3-way toggle switch have exactly the same combination. Once you push down BV, whatever the combo that was before in the current position comes back.
By example, imagine we had BV = down, NV = up, NT = up and BT = down and we had selected Rhythm position, we should have selected Neck Inner Coil but, once BV is up, we are having Bridge humbucker in series with Neck Inner Coil Out-of-Phase.
Imagine that, while in series, we change to Treble position. There is no change in the sound, since we are getting the same combo but, once we push down BV, we are getting Bridge Humbucker, instead.
 
As in the case of JP's wiring, volume controls are independent and allow you to mix both humbuckers at your taste but, when both pickups are in series (BV = up), both controls are also in series so, rolling off a bit  one will also reduce the overall volume and, totally rolling off one we will shut up the guitar. In this case, the neck volume acts as some kind of master volume.
 
In the middle position (and in parallel, BV = down), you will achieve different nuances by mixing each pickup at different levels, since some frequencies will be reinforced while others will be dimmed.
Also, when in middle position and out-of-phase (NV = up), the different volume levels for each pickup, will give you different textures of the out-of-phase sound (Peter Green's mod), some are edgier, some are more subtle.
Just experiment with all this.

46 comments:

  1. working on this mod right now. having trouble with the bridge pickup though. with all knobs down as normal the bridge is split. I've triple checked my connections. maybe a fresh look tomorrow will reveal my mistake.

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    Replies
    1. What I can certify is that this mod works flawless. I've got it in my LP-clone guitar, for several years.

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  2. If bridge pickup is working full when the bridge tone pull/push is up then, reasons can be two:

    1) your pull/pushes works in a reversed mode so, when they are pushed, the upper lugs enter in contact with center lugs, instead of being the lower lugs
    2) you missurdestood the diagram and reversed lower and upper lugs in this pull/push. Check also other pull/pushes, then.

    You must see diagrams as if components were already mounted in their holes/pickguard. So, the pull/push lugs closer to the pot's lugs are the "upper" lugs of the pull/push if you stand it facing their lugs and with the shaft pointing to ceil. And those, farer from pot's lugs are the "lower" lugs of the p/p. See that tone pots are reversed in the diagram and, this can lead you to some confusion.

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  3. Wonderful job, man.

    I'm new to building guitars and I was looking for a diagram for a Les Paul in a Jimmy Page style. I will try to develop The Exchanger MOD 2, but I must confess that I got a bit confused with the pickups wires color. Can you bring some light?

    I'm also thinking in using .022 mF PIO capacitors. What is your opinion?

    Thank you much.

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    Replies
    1. Color wires of pickups corresponds to Seymour Duncan ones. White color is being represented in light blue, for readibility.
      About using 0.022 uF PIO caps; I don't see any issue. I like more the amount of high end that rolls off a 0.047 uF cap but, that's my particular taste.

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  4. Thank you for the information.

    Recently I watched this tip from StewMac (http://www.youtube.com/watch?feature=player_embedded&v=e0SLdOWvz3c) and I got myself thinking if I could use it with your diagram above. Do you think it is feasible and it will work properly?

    Thank you again.

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    Replies
    1. What you found there is what is commonly named a "treble bleed mod", one of the three. Please, look to my DIY Wiring Page and search for Treble Bleed mod.
      It's compatible with any wiring but, take into account the following: my design includes the '50s tone mod that gives some bright to humbuckers and rolls off trebles in a very natural way when rolling off the volume.
      You can always try it as it is and, if you still think you need the treble bleed, go for it. Nothing wrong

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  5. thank to your great wiring, i had applied this on my LP.
    but there's one i'm wondering since i use this mod, on normal condition (no pulling pot, all PU switched on) Volume Controls (N&B) can't be reduced till zero (pot on zero position but still produce sound).
    Is it normal or i had a wrong wiring.
    Thank you for your response.

    ReplyDelete
    Replies
    1. This is a known issue or drawback, related to independent volumes.
      For certain guitars, it happens that there is some bleed from pickups, even with pots at zero.
      Maybe, it's something related to pots themselves (honestly, dunno).
      I have not such an issue in my axe but, it doesn't mean that you wired it wrongly. It's a knows side effect that takes place, some times.
      But it should deliver very very low ouput in that case, otherwise, some ground could be bad (cold solder or similar).

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  6. Thanks for sharing!
    Does one of the pick-ups need to be magnet flipped?

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    Replies
    1. You're welcome!.
      Absolutely not. Otherwise, you would be in "Peter Green's mod" in middle position by default.

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  7. Dear Hermetico,

    I have built your LP-Exchanger mod2, and I have the issue which is reported by aL_saTyr (November 16, 2013 at 2:48:00 AM GMT+1).

    It is very annoying, I would like to extinguish it.

    Please tell me more about your experiences with this issue, if you have. And plaese, let me know what kind of humbackers, capacitors, and potentiometers do you use, to avoid the issue.

    Thank you for your help.
    Viktor

    ReplyDelete
    Replies
    1. Best way to get rid off this issue is to go for modern wiring (dependent volumes).
      Also, DON'T USE TREBLE BLEED MODS with this wiring !!!
      It will not work properly.

      Delete
  8. Hi Hermetico,

    You've done a great job with this LP-Exchange wiring, and I can't wait to give it a try.

    I have a question about it, after studying the diagram a bit, I don't understand how can the BT pot split the bridge when it's up if there is no way the two cables from the pup connect to ground, can you clarify this to me?

    Cheers

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  9. Do you typically solder the ground wires to the bottom of the pots? I worry about burning them out. I would just connect the ground lugs to a central ground, but the neck volume pot's ground lug isn't directly grounded in this diagram.

    Thanks.

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  10. I have the same issue as Brad. With the BT down the coil is split. The wiring is exactly as drawn here. Is there a fix for this?

    ReplyDelete
    Replies
    1. I have the some issue. BT down splits the bridge coil, up is normal humbucker.

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  11. There may be an error in the provided diagram causing the bridge coil to be split when BT is pushed down.

    I resolved the issue of "BT splits coil when in down position" by moving one wire on BT pot switch. The wire I moved is indicated in dark blue on the original schematic.

    On the schematic the dark blue wire is connected to the left DOWN LEFT pin of BT Pot/Switch. I moved it to the UP LEFT pin of the BT pot/switch. It resolved the issue. Hope it helps somebody!

    By the way, Thank you Hermetico for a great mod which now works as designed!

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  12. HermeticoGuitar - Do you agree with Jacek and the wiring change?

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  13. One of the blue connections to the BT pot/switch is incorrect in the diagram, as stated above it should be nearest to the pot so it is only enabled when in the 'Up' position. How the diagram is currently drawn when in the default (all down) position the bridge red/white wires would be routed through the NT switch, then the NV pot connection to the output switch. This would short the the north coil (black & white as per SD wiring) so only the South coil (red/green) is active. I hope this information helps.

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  14. I wired this thing to a T, including switching the BT blue wire. When I pull the BV it sounds like my tone control is at 0, definitely not in series. When I'm on the bridge pickup everything in all positions (out or in) sounds like my tone is at 0 as well. Any ideas?

    ReplyDelete
    Replies
    1. I don't see why you would be losing all high frequencies for the bridge pickup or in the series option (BV out) unless there is a wiring error somewhere in your setup. Are you sure the connections of the bridge volume are correct to the bridge tone pot? One simple test would be to disconnect the cap to the bridge volume pot, as this will take the bridge tone control out of the circuit completely which will help you to isolate the problem.

      Tom

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  15. Trying to decode the colors and getting stuck.

    Can you do this with push push knobs?

    ReplyDelete
  16. A quick point regarding orientation…

    If you hold the pot with the shaft pointing toward the floor and the lugs facing you, this is how you'd see the lugs:
    A D
    B E
    C F

    That is how the NV and BV pots are oriented in the drawing.

    But the NT and BT pots in the drawing are shown from a different angle (upside down), so the lugs are:
    F C
    E B
    D A

    Given that, are you other commenters sure that dark blue wire connected to lug D of the BT switch in the diagram should really be connected to lug F instead?

    The comment above specifically says "How the diagram is currently drawn when in the default (all down) position the bridge red/white wires would be routed through the NT switch, then the NV pot connection to the output switch." I think you meant BV rather than NV? But other than that, your comment seems right to me.

    Hermetico, any thought?

    ReplyDelete
  17. I've now done this wiring in my Ibanez AS73. Some comments…

    I think you definitely do need to connect the dark blue wire (coming from lug B of the NT switch) to lug F of the BT switch, *not* to lug D of the BT switch.

    Accomplishing this wiring in a hollow body is difficult. First, you have to route all the wires around the F holes so they're not visible. That means longer wire runs, so you need to think about shielding (I ran everything inside a long expandable braided wire shield that was grounded, and just poked wires through as needed at each control). Second, fitting the harness with push/pull pots through the F holes is a huge pain (especially with large Vitamin Q caps that have stiff legs). It can be done, but you'll definitely be bending and stressing all the solder joints in the process.

    If you have the toggle in the middle position, you have to turn *both* volume knobs all the way down in order to kill the sound. That's due to the parallel wiring scheme. That is different than how typical Les Paul controls work, in which turning either volume knob all the way down will completely kill the sound with the toggle in the middle position.

    Even with both volumes turned all the way down, I can hear a tiny bit of electrical buzz/hum through the amp. Perhaps that's just something about how one of the connections in my harness turned out (though I tested them all), but on my other guitars, any electrical hum is completely silent (grounded out) when the volume knob is all the way down. It's really only audible with the amp on high gain.

    I used DiMarzio pickups so connected the DiMarzio's red wire instead of a Duncan black wire, DiMarzio black instead of Duncan white, DiMarzio white instead of Duncan red, and DiMarzio green same as Duncan green. The result is that if I pull just the BT that leaves the bridge pickup's rear coil active. If I pull just the NT it leaves the neck pickup's rear coil active. If I pull both the BT and the NT, it leaves the front coil of each pickup active. (Note that on the bridge pickup the "rear" coil is the outer/screw coil, whereas on the neck pickup the "rear" coil is the inner/slug coil.)

    Really versatile wiring scheme, Hermetico! I actually really like having the coil cuts on the tone controls instead of the volume controls.

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  18. Hermetico thank you very much for sharing your wiring schematic.
    I am loving all of the new tones and versatility I am getting with my LP.

    I have to admit it took me several attempts to get it right because I:
    1) chose this mod as my first ever wiring project (it is advanced and I love a challenge);
    2) misinterpreted the orientation of the pots;
    3) converted the diagram terminals (A D, B E, C F) to the new CTS DPDT pot terminals (1 3, C1 C2, 2 4); and
    4) converted Gibson PUP color codes to SD color codes (Gibson QC neck and bridge PUPs do not use the same color codes).

    I also want to point out that the OP (Jacek Zalewski) is correct about moving the blue wires on both of the tone pots.

    Thanks again and I sincerely appreciate all the time you put into creating this mod.

    Jennifer \m/

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  21. bugsysiegals, Look at this drawing as if your pull/push pots are already installed in the guitar. So you're looking at the back of your guitar at the middle of electronics cavity (the shafts of the pots pointing down)

    Also notice both BT and NT pots are "facing" both BV and NV pots with their terminals. as seen on the diagram.

    Also make sure you solder blue wire on the BT potentiometer to proper location (move it from bottom left to top left in the drawing which will be to the terminal which is closer to the shaft.


    Be aware that pickups wire colours ot this schematic correspond to Seymour Duncan pickup wire colours. (Gibson uses different wire colours. Additionally if you plan to retrofit Gibson quick connect pickups be aware that Gibson Bridge pickup with Quick Connect does not follow Gibson wire colour codes! - couple of wires are reversed!)

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    3. FWIW - the Blue wire comment above is incorrect and it's actually the Blue wire on the top left of the NT which should be moved to the bottom left of the NT.

      I figured it out by studying the diagram and struggling to understand why the Bridge IC/OC were always backwards until I tried to interpret as if the shaft is always below the 6 pin boards, irregardless of where the lugs are, and when pushed in, connect the middle with what you see as the top pins without ever rotating the diagram.

      The correct pin layout for ALL pots while viewing as-is without rotating is ...
      4 3
      c2 c1
      3 1

      or

      F C
      E B
      D A

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  22. Hi Hermetico

    Thankyou for sharing this information I've learned a lot from this site

    I'm going to have a go at this mod, however I'm not sure of the connections on the pot's
    Here is a link to some pictures are these correct

    https://1drv.ms/f/s!AvqamFgG8hdpiSZY3-05jZv-dGwT

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  23. There exists several other errors in this diagram.

    1) The Fuscia wire from Lower Right of NT should connect to the middle lug of BV otherwise volume cannot be controlled when the Neck is in split coil mode.

    2) The Lower Right Orange from BV should be connected to the Left lug of the NV pot otherwise when NT is pulled the split coil Neck pickup volume cannot be controlled.

    3) The Orange from Upper Right BT should be connected to the Middle lug of the NV rather than Left lug.

    Note: The output jack/switch should not be connected to the same lug as the pickup which is the case in the current drawing for Fuscia and would also be after moving the Orange from BV. Once these changes are complete, at least mentally, you can decide to alter whether pickup or switch should be swapped between Left/Middle lugs to change between Modern and 50's wiring. Additionally, you can swap the capacitor on Neck volume between pickup/switch (Left/Middle lugs) to determine Master or Independent volume control.

    All that said, my guitar is working well but if I turn down both volumes, and turn up the opposite pickup volume, I can hear a very faint signal. Perhaps I have some sort of shorted wire. If I find something else wrong with the diagram I’ll advise but otherwise these changes will get you what you need.

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  24. I've done followed this schematic 4 times now, I will attest it works.
    The comment about the dark blue on the BT needing moved is also correct (this allows it to split in the up position).
    I feel this is absolutely brilliant. Thanks so much for the design and effort!

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  25. I made this on my guitar in 2018. It still sounds amazing. Thank you!

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  26. The wiring has few flaws in it:
    * BT is wired to have coil split on by default.

    * Bridge coil split by-passes volume control and volume causes the bridge pickup to go out-of-phase with itself. This also means bridge pickup will always have some volume go through.

    * Neck pickup also shares the same kind of volume issue.

    * Series mode goes through bridge and neck volume control, which causes less balanced output while in series mode.

    http://u.meelo.org/JimmyPageWiringMod.png
    I fixed the bridge pickup issue and re-drew the schematic as such. But this has not touched the neck pickup or series mode issues at all. I have drawn those fixes to a piece of paper, but haven't bothered to fix the issues to the schematic above.

    As this JP mod seemed to be just as flawed as everything else I found from the interwebs, I came up with my own schematic where I addressed all of these issues and now that is wired to my guitar. I ended up not being bothered about having 22 modes. 21 modes is enough for me, especially now when they all actually work.

    --
    Milo

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    1. in case anyone is interested to try yet another schematic, this one is mine:
      http://u.meelo.org/milo-4pp-wiring_hq.png
      and pin-by-pin instructions.
      http://u.meelo.org/milo-4pp-wiring_pins.jpg

      It may not be in the best format possible for reading, but the hand-written pin-by-pin layout should help.

      --
      Milo

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    2. I updated the picture mentioned in my original post to be up-to-date with all fixes.

      Maybe image tags are allowed here?
      [img]http://u.meelo.org/JimmyPageWiringMod.png[/img]

      if not:
      http://u.meelo.org/JimmyPageWiringMod.png

      P.S. it seems like Bugsysiegals came to the same conclusion on what's broken and how to repair them.

      --
      Milo

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    3. I'm glad you've attempted to correct the diagram but you have an issue ...

      With all pots pushed in, nothing should be split; however, you have Bridge Blue/Red going to ground which splits to Bridge IC. This is because you moved the Blue wire on BT from Lower Left to Upper Left and instead you should move Blue wire on NT from Upper Left to Lower Left.

      That said, you've all the changes I've made except you also modified the BV Upper Right to come to the Left Lug and Lower Left to go to the Middle Lug. I can see by not doing it, with BV pulled out, the original diagram allows the Neck pickup and Bridge switch to go directly to the capacitor and only the switch should go directly to the capacitor in 50's wiring. I wonder how this impacts my tone and now I will be considering to change it ... good catch!

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  27. Hi all,
    I implemented this mod to my Les Paul a couple of years ago. Just changed one wire as someone said. The scheme works superb, thank you very much, Hermetico. I'm running it with a pair of Seymour Duncan P-Rails.

    I was wondering if this mod has 50's wiring implemented, as I believe it looks like modern LP wiring.

    All the best, thanks again.

    ReplyDelete

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