Need Help - 'Modern' vs '50's' wiring...comments and votes please | The Canadian Guitar Forum

Need Help 'Modern' vs '50's' wiring...comments and votes please

Discussion in 'Guitar Building/Mods/Repair' started by greco, Oct 17, 2017.

?

Your preference is?

  1. 50's wiring

    77.8%
  2. Modern wiring (no treble bleed)

    0 vote(s)
    0.0%
  3. Modern Wiring with treble bleed

    22.2%
  4. I can get used to anything...just go play the darn thing

    22.2%
Multiple votes are allowed.
  1. greco

    greco Gold Member

    Joined:
    Jul 15, 2007
    Location:
    Kitchener, Ontario
    To those of you that have tried both forms of the wiring and can compare, what are your preferences and....(briefly) Why?

    Any comments on the specs for the cap and resistor in the treble bleed circuit?

    IF you have never tried either, feel free to comment and vote based on what you think you would prefer.


    Mod Garage: Decouple Your Volume Controls

    Dirk Wacker
    July 18, 2014

    [​IMG]
    Wiring diagram courtesy of singlecoil.com.

    Here’s an easy but effective mod for Les Paul slingers that solves a problem they’ve been living with since the model’s introduction more than a half century ago. This project also applies to most other guitars with dual humbuckers, individual master volume and master tone knobs for each pickup, and a 3-way pickup selector switch.

    The problem (or not). The Les Paul circuit dates back to the mid ’50s. It has changed slightly over time—Gibson used several different tone caps and experimented with tone-pot wiring—but essentially, modern Les Pauls employ the original wiring.

    One thing Gibson did not change was the concept of coupled volume pots. You know how this works: With an independent pair of controls for each pickup and a 3-way toggle switch, you can dial in your lead volume and tone using the bridge pickup, set up a rhythm tone using the neck pickup, and then quickly change from lead to rhythm and back using the 3-way switch. This works great—two preset sounds at your fingertips.

    But Les Paul players know what happens when you use the middle position of the 3-way switch: The pickups are wired together in parallel, so when both pickups are engaged, rolling down the volume of one even slightly while leaving the other fully open makes the latter much louder than its mate. Even worse, backing down just one of the volumes to zero shuts off the entire guitar.

    Why is this? Because the two volume controls are not decoupled, they interact. With a passive circuit like this, it’s just the nature of the beast. Consequently, the dual-humbucker world divides into two opposing camps: The first doesn’t consider this interaction a problem. It’s simply part of the game—get used to it. The other camp regards this interaction as a system error and tries to eliminate it.

    Les Paul players know what happens when you use the middle position of the 3-way switch: Backing down just one of the volumes to zero shuts off the entire guitar.
    Now, the only real solution for this problem—assuming it’s an issue for you—is to switch to active circuitry. All other “solutions” are compromises that may or may not appeal to you. You must let your ears decide.

    Swap it out. It’s easy to wire a Les Paul so the volume controls work independently: You simply wire the volume pots backwards. (This is how some Rickenbacker guitars and early Fender Jazz basses are wired.)

    First, study the wiring diagram shown here. It represents the modern factory wiring typically found in Les Pauls. The black wires are ground; the white wires are the hot connections from the pickups and to the output jack. The black wires that run from pot to pot form the “ground bus.” Be careful not to close this ring—leave the connection between the two volume pots open, as shown in the wiring diagram, otherwise you’ll create a perfect antenna that picks up all kinds of funny noises. (For a noise-free circuit, it’s very important that the ground bus uses a solid, not too thin wire and strong soldering spots.)

    Now, simply interchange connections 3 and 2 on both volume pots, including the tone cap connections. That’s it! Leave all connections on the tone pots untouched. You’ve now wired both volume pots backwards, thus decoupling them.

    Time to network? There’s a big downside to this mod: When the pickups are wired backwards, they “see” less resistance, and the output impedance rises. This results in dramatic treble loss when you roll back the volume. It’s an idiosyncrasy of passive guitar systems: When you turn down the volume, even just a bit, treble loss is not proportional: A small cut in volume creates a far greater loss in treble response. And the treble loss is even worse when the volume pots are wired backwards.

    You can combat this by adding a treble-bleed network between the input and output of each volume pot. This usually consists of a small capacitor, often with a resistor in series or parallel. Simply solder the treble-bleed network between lugs 3 and 2 on each volume pot and see if it sounds right to you.

    As far as capacitor and resistor values, that depends on how much treble you like. Some people prefer using a capacitor only (aka “treble bypass cap”), while others like a cap with a resistor in parallel. A useable range for the cap is from 220 pF to 680 pF; a resistor wired in parallel can range from 150k ohm to 330k ohm. A popular choice for a cap-only solution is 330 pF. For a network solution, many players like a 470 pF cap with a 330k-ohm resistor wired in parallel. You could start with this and see what sounds best to you. Small silver mica caps sound excellent for this mod.

    Remember, passive circuitry can never add anything that isn’t already there, but it can reshape the tone by deemphasizing certain frequencies, which makes others more prominent. This treble-bleed network filters bass so the highs are more pronounced.

    Until next time, keep on modding!


    [​IMG]
    Dirk Wacker lives in Germany and has been a guitar addict since age 5. He’s also a hardcore DIY-er for guitars, amps, and stompboxes and runs a website on the subject (singlecoil.com). When not working at his guitar workbench, he plays country, rockabilly, surf, and flamenco. Contact him at [email protected].
     
  2. greco

    greco Gold Member

    Joined:
    Jul 15, 2007
    Location:
    Kitchener, Ontario
    This is a post from @mhammer in a thread from 2010.

    The thread was started by @GTmaker
    https://www.guitarscanada.com/index.php?threads/gibson-es-335-volume-controls-question.33233/

    As noted, perfectly normal for that guitar and many others that use dual volume controls. Here is a schematic (now missing) of similar wiring for a Les Paul. The Volume pot is the 500k audio to the left on the diagram. The volume level will be a function of the proportion of resistance "above" the arrow (wiper), relative to the total resistance of the pot. So, as the resistance between the wiper and ground gets smaller, the volume is decreased.

    When only one pickup is used at a time, those pots work in exactly that fashion. When BOTH pickups are on, however, the wiper from each pot is connected to the same point. This means that the resistance between the wiper and ground of each volume pot is placed in parallel with the other one. Right away, that makes for a smaller resistance to ground, which will necessarily limit the volume attainable.

    For example, if the neck volume is set low such that the resistance going to the wiper is 400k (of the total 500k), and the wiper-to-ground resistance is the remaining 100k, then even if I turn my bridge volume up to max, the resistance between the wiper and ground will be 500k+100k or 83.3k, when both pickups are on.

    Of course, once you go from N+B to bridge alone, that 100k in parallel is removed and the max volume is restored. There is no doubt that volume presets for each individual pickup can be useful, however a basic system, such as used in a great many guitars, can provide enough awkwardness for those who like to use both pickups, that many can find a single master volume more convenient. Six of one, half dozen of the other, eh?
     
  3. hollowbody

    hollowbody

    Joined:
    Jan 14, 2008
    Location:
    Toronto, ON
    I prefer 50's wiring. I like the way my pickups sound with it wired that way. It's a little brighter, which is never a bad thing for me when it comes to LP-style guitars in a band mix. I'm not a knob-fiddler when it comes to volume, but I do use the tone knobs a little bit. I like that the tone knob cuts treble, but also a little bit of volume with the 50's wiring, allowing me to give the knob a small tweak to bring things down if I want to.

    There's not really a right or wrong, though. It's more what you get used to ergonomically. In all honesty, any sort of tonal difference can be accounted-for or achieved through EQing on the amp/pedal/board anyway.
     
    greco likes this.
  4. BSTheTech

    BSTheTech Gold Member

    Joined:
    Sep 29, 2015
    Location:
    Earth
    Watching...
     
  5. Hammerhands

    Hammerhands

    Joined:
    Dec 19, 2016
    Location:
    Winnipeg
    After playing my Gretsch for so long, I hate my Gibson's controls.

    Master Volume, Neck Volume, Bridge Volume, Tone if you must.

    You could run just one volume control to mix in the bridge pickup in the middle position, hot rod wiring.

    The Gretsch circuit is similar to the mod, without tone controls and without the treble bleed. It works great, start with the guitar wide open, roll back the master volume to about 80% [so you can turn it up when you need it], adjust the balance between the pickups to taste.

    Another thing about the regular Gibson wiring is that tone controls are not independent in the middle position. That's what always trips me up. You can get a decent sound out of one or each of the pickups, but it hardly ever works out in the middle position [and the middle position is where I usually leave it].

    Another better than standard solution, in my mind, would be to have the middle position drop one tone control and run one pickup wide open. A 3P3T switch, or maybe DPDT.
     
    Last edited: Oct 17, 2017
    greco likes this.
  6. greco

    greco Gold Member

    Joined:
    Jul 15, 2007
    Location:
    Kitchener, Ontario
    Any thoughts/conclusions?

    Are you about to do or have this wiring done?
     
  7. BSTheTech

    BSTheTech Gold Member

    Joined:
    Sep 29, 2015
    Location:
    Earth
    Was thinking about it. I have two Les Paul's, both with the circuit board. I initially hated it, but playing with the pickup heights really sweetened them up. I like the push-pull pots too. Might install the 50's wiring as an experiment. See how long and wet this winter is.
     
    Tone Chaser and greco like this.
  8. tonewoody

    tonewoody Gold Member

    Joined:
    Mar 29, 2017
    Location:
    Canada
    I am not seeing 50's wiring in the above diagram.
    Edit: (Thanks for adding them Greco!)
    ******
    I have done a few teles with 50's wiring. I took the time to rig up a temporary toggle switch and test it out to hear the differences. It's fairly subtle but the 50's wiring has a clarity that the modern lacks IMHO.

    I highly recommend taking the time to rig up a temporary switch whenever you do any wiring mods, try out different caps/pot values/ treble bleeds etc.
     
    Last edited: Oct 24, 2017
    greco likes this.
  9. greco

    greco Gold Member

    Joined:
    Jul 15, 2007
    Location:
    Kitchener, Ontario
    I thought the diagram was for modern (decoupled) wiring

    [​IMG]
     
    tonewoody likes this.
  10. tonewoody

    tonewoody Gold Member

    Joined:
    Mar 29, 2017
    Location:
    Canada
    My brain has 50's wiring....thanks for the visual aide....!
     
    Last edited: Oct 24, 2017
    Tone Chaser likes this.
  11. greco

    greco Gold Member

    Joined:
    Jul 15, 2007
    Location:
    Kitchener, Ontario
    My brain is still using the original set of tubes...from the '50's!
     
    epis, Tone Chaser and tonewoody like this.

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