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Thread: Les Paul Lo-Z pickups

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    Quote Originally Posted by David Schwab View Post
    Just in case you scanned this, and for others that scan things like this, please scan in grayscale, not as line art. So in other words, scan for a photo not for text, that way the images don't turn out as black blobs. You need to scan at least at 600 ppi for sharp text, and you might need to adjust the levels to get the background white and the text black, bt it would look so much better and preserve these ads for prosperity.
    Plus, that is such a great ad, it would be great to see it in its "monstrous" detail! Thanks for sharing it!

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    I'll repost the ad with a better job scanning it.....................


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    Last edited by Grog3; 08-06-2013 at 03:19 AM.

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    Thanks David! I've tried to limit myself to Gibson guitars & basses, matching sets when possible. If I would have included Fenders etc... it would have gotten further out of hand than it did. The Triump basses have gone up in price lately. I only paid $300.00 for my first one aprox 20 years ago. It didn't end up being such a bargain though, seven more low impedance Les Pauls are now keeping it company. I just added the Les Paul Personal last spring, that was the hardest one to find. They were either asking way too much or were in rough shape.

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    The Triumphs were a lot more reasonable back then. I missed the chance to pick one up a few times, as well as the recording guitar.

    I used to own an EB-2DC similar to the one you have.

    Here is is at its current home. I had made a few modifications; replaced the nylon saddles with aluminum saddles, and replaced the useless baritone switch with a 6-position varitone. It also now totally bypasses that circuit when it's on position 1. The original wiring always had a mid cut going on.

    Now that I make better sounding pickups for these basses I wish I kept it!


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    It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. Albert Einstein


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    Quote Originally Posted by David Schwab View Post
    The Triumphs were a lot more reasonable back then. I missed the chance to pick one up a few times, as well as the recording guitar.

    I used to own an EB-2DC similar to the one you have.

    Here is is at its current home. I had made a few modifications; replaced the nylon saddles with aluminum saddles, and replaced the useless baritone switch with a 6-position varitone. It also now totally bypasses that circuit when it's on position 1. The original wiring always had a mid cut going on.

    Now that I make better sounding pickups for these basses I wish I kept it!

    I've had the '67 EB-2 for coming up on 40 years, I think it has better tone than the EB-2DC. All of my mudbuckers sound a little different, but the EB-2C's pickup has the smoothest, least raspy sound, ( if that's a real word??!). I bought the EB-2DC from a store called High Tec Consignments in Minneapolis. Shortly after I bought it, the store was bought by Play it Again Sports. From this store, they started the Music-Go-Round franchise. I bought the 1959 EB-2 because it had one of the last of the single coil pickups, same as the original EB-1. They switched to the Humbucker in early 1959.

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  6. #111
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    Thanks for posting the ad again, in color this time - very cool!

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  7. #112
    Pickup Maker David Schwab's Avatar
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    Quote Originally Posted by Grog3 View Post
    All of my mudbuckers sound a little different
    This is true. I had picked up a NOS mudbucker at the same time I had the EB-2. It's was clearer sounding than the one in the EB-2. At some point I swapped the two pickups and put the one from the EB-2 in my Rickenbacker. Then I rewound that one to about 12k. I also added two more magnets, which is how the NOS pickup was. Ive also seen some with alnico and some with ceramic magnets.

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    It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. Albert Einstein


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    Question Les Paul Low-Z Pick-ups

    Dear David, I found your page from Music Electronics Forum. You were in a forum thread about Les Paul Low-z Pickups. I have this pickup in my Gibson EB-3 1967. I bought the bass new at Victor's House of Music in Bergen Co. NJ and in 1974 had Alex Dumble, Dumble Amps fame, wire the low-z pickup. I constantly search for info on Dumble and the pickup because about 10 years ago I tried to repair the chicken head rotary switch and f'd up the connections, never getting back the combination of tones Dumble had made. This Thread is THE most comprehensive discussion I have come across about this pickup. IS there ANY way to resurrect the thread? There were a few contributors, one in particular who had put a low-z in a Fender bass.

    I can answer a couple of the questions you were asking in the thread. This pickup CAN go straight to the recording board. I recorded at Steve Boone's Blue Seas studio in Baltimore and went straight to the board with headphones and it was almost heaven. Second, Alex Dumble had wired my Fender Bassman (cbs silverface) with a small low-z transformer in channel 1 to take one wire of the stereo out XLR cable while the other high-z wire(both were 1/4" jacks) went to channel 2 of the Fender. Strapped for money I sold the amp and used the standard in-line mic low-z to high-z transformer and still do. Into a small mixer, then into an amp.

    I used the LP Studio bass drawings and that wiring made for crap sound. All 4 positions sounded the same. Alex had made: Neck pickup sound/fuller-more coil sound/FULL-all coils sound/ and OUT-of PHASE. I found a Ripper schematic that had out-of -phase and swiped that to make my homemade schematic. But I am not inclined this way. I include it here along with a photo of my bass.





    EDIT: This was the Thread that got me started. Thank you all. This is a fascinating group. Especially for a musician/bassist like me who has limited electronics skills.
    https://music-electronics-forum.com/...ead.php?t=3737

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    Last edited by DeepFrequency; 03-28-2020 at 09:39 PM. Reason: photo

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    Quote Originally Posted by jmiked View Post
    Interesting thread......

    I have a Les Paul low-z pickup I got from eBay. The mounting ears were broken off, so I haven't yet used it for anything, but I did take DC resistance measurements from it. Mine is coil-tapped, and I can dig the measurements from my notes of the time if anyone is interested,

    I built two low-z pickups from that info... I used 1100 turns of 34 gauge wire to produced two coils of 150 ohms each, on a stacked frame. I liked the Agile Les Paul copy I had, so I bought another one, spent two days (mostly setup time) on a friend's milling machine routing out larger holes for the pickups and ended up with a very nice sounding instrument. One of the hardest things about the construction was finding the proper value pots. I ended up using linear pots instead of audio taper, because that was all I could find after 3 months of research.

    It sound very, very close to the sound on the Les Paul and Mary Ford albums.

    If anyone is still interested, I can furnish more info on the process (I took photos during the project), and on info I found out by talking to the fellow that does the sound board for Les at his Monday night gigs and has known him for 25 years.

    Mike
    Mike if your still out there...What size Pots did you use? I am re-building my Gibson EB-3 modified in 1974 with a Les Paul Studio low-z pick-up. I would have sworn Dumble left the original pots in and it ran to a Fender bassman with a low-z transformer. But what i read here the 250K Gibson pots should not work?

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  10. #115
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    Quote Originally Posted by clementc3 View Post
    I posted this in the "Stacked humbucker bobbins/Les Paul Recording pickups thread" also:

    I recently acquired a 1970's Les Paul Recording guitar with the low-impedance pickups and I want to take advantage of the low-impedance output without using the transformer that is built into the guitar.

    There are several low-to-high impedance transformers that I can put at the amp end of my cable but I wondering how low the "low-impedance" output from the guitar is. For example, Shure has their A95U which can accept low-impedance input in the 75-300 ohm range or 19-75 ohm (if you re-solder a lead), while Electro-Voice has their E-V 502CP at 150 ohms. Radio Shack has one at 900 ohms (I think).

    Reading this and other threads I see people say the Les Paul Recording pickups have values of 10 to 150 to several hundred ohms.

    Which impedance matching transformer is most appropriate, and does it matter?

    (Note that my electrical knowledge is from one physics class that I took in 1975 - about the same time that my guitar was being marketed by Gibson - AND my electrical knowledge has not been updated since, so it's pretty rusty!)

    Thanks for your collective knowledge!
    FYI- I have used several different models after I sold the matching Fender amp I had. The Shure works well.

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  11. #116
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    Quote Originally Posted by bajaman View Post
    This is all I have - feel free to ask questions - I traced this out when I was still a teenager - long long time ago - lol
    The attachments have been long gone. Are you out there still? Will you re-post them please?

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    Quote Originally Posted by David Schwab View Post
    Here's what I have.

    I colored that one in back in the 70's so I could follow the wires.

    I threw in the photo just for the shock value!
    Hi Dave, thank you for the invitation to open this thread again. If I could ask for a re-posting of the drawing that were once here please? Thank you.

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    Quote Originally Posted by clementc3 View Post
    You may have already seen this page on the whole range of Les Paul low-impedance guitars:

    Les Paul Recording Guitar Users Forum

    About 2/3 of the way down is a short section regarding the Les Paul Signature.

    A schematic is here (in the lower right corner of the jpg):

    http://www.guitar-parts.com/images/lespaul.jpg

    Information on the cream-colored low-impedance pickups is impossible to find as far as I can tell. I have an Epiphone Les Paul Signature with similar looking (but possibly quite different) cream-colored "Electar" (one of Epiphone's proprietary brand names) pickups. The Epiphone LPS only has one high-impedance output jack while the (real) Gibson LPS also has that and also a low-impedance output jack which completely bypasses the internal transformer.

    On my Epi LPS the 50-250-500 rotary switch selects different taps of the internal transformer with VERY significant changes in tone. (Can anyone here explain the science behind this for me? )

    For the sake of completeness here are two other sites with lots of information about Les Paul low-impedance guitars:

    Woody's Gibson Les Paul Recording guitar page

    Les Paul Personal

    I have had a good experience using the Shure A95U transformer with the low-impedance output from a Les Paul Recording guitar (to enable one to plug into a regular guitar amp) and I would think you can use this with the low-impedance output from a LP Signature. I use the Shure A95U in its off-the-shelf 75-300 ohm configuration; it is reportedly a simple task (if you know what you are doing, which I don't) to change the internal wiring for 19-75 ohm input, which is supposed to be even better.

    Please post here if you find more information about the Les Paul Signature!
    FYI- I will second the information about the Shure inline transformer. My original Dumble set-up was an XLR plug in my bass(still is) ground/humbucker/low-z to an XLR female. This is a standard mic cable I can buy anywhere. Then I keep in my case the Dumble made XLR male split-Y to two 12" leads ending in 1/4" phone jacks red/black - highz/low-z. My Fender bass was one channel high-z and channel two modified to low-z with a cool little low-z transformer inside. About the size of a shot glass. I sold that amp and used the Shure for years and it sounded the same.

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  14. #119
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    Quote Originally Posted by David Schwab View Post
    The Triumphs were a lot more reasonable back then. I missed the chance to pick one up a few times, as well as the recording guitar.

    I used to own an EB-2DC similar to the one you have.

    Here is is at its current home. I had made a few modifications; replaced the nylon saddles with aluminum saddles, and replaced the useless baritone switch with a 6-position varitone. It also now totally bypasses that circuit when it's on position 1. The original wiring always had a mid cut going on.

    Now that I make better sounding pickups for these basses I wish I kept it!

    SWEET BASS!

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  15. #120
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    Quote Originally Posted by DeepFrequency View Post
    Mike if your still out there...What size Pots did you use? I am re-building my Gibson EB-3 modified in 1974 with a Les Paul Studio low-z pick-up. I would have sworn Dumble left the original pots in and it ran to a Fender bassman with a low-z transformer. But what i read here the 250K Gibson pots should not work?
    The rule of thumb for volume control value is to find a pot value that is between 35 to 50 times the total DC resistance of the pickup coil or coils if wired in series. This will give you a resistance range in which to find a standard pot value.

    Joseph J. Rogowski

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    Quote Originally Posted by bbsailor View Post
    The rule of thumb for volume control value is to find a pot value that is between 35 to 50 times the total DC resistance of the pickup coil or coils if wired in series. This will give you a resistance range in which to find a standard pot value.

    Joseph J. Rogowski
    Earlier in this thread the Les Paul low-z pickup (just one) was determined to be about 10ohms. Times 50: 500ohms or .5K Pot. is that correct per your formula? The schematic posted for two of these pickups is 2.5K. All help appreciate here as this is not my field. Would applying the guitar notion that if you had 250K pots but wanted more control use 500K pots work as well here? i.e. a 2.5K pot to a 5K pot? I ask because I have 5K pots and can't find the lower value.

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    Major break through on how the Les Paul pickups were wired with the coil taps and 8 wires per pickup. Using the photo from Fly Guitars webpage and the schematic I colored the schematic as suggested by Dave and the drawing did not match the photo. So I colored the drawing to match the photos then traced back the circuit following what pickup and what coil were put into play in the 3 "Tone" choice switch. Like I said big break thru!!


    First off the Brown leads go to the Phase switch, The unseen Brown to the unseen Selector Switch. The drawing has them as Green so the Drawing is backwards.

    So look at the photo and you see two gangs of 6 lugs each: They run off into two large black wires to the pickup selector switch at the top of the bass. The connections to the 12 lugs are far from what is pictured in the drawing AND why when I wired per the drawing is sounded all flat with no tone change at all.

    Looking at the photo left to right Position #1 is Bridge pickup (photo top row of gangs - with the brown leads as per interpreted drawing)
    POSITION #1 BRIDGE RED/BLUE: IN RED 500 TOP COIL - OUT BLUE 750 BOTTOM COIL ~ NECK GREEN/BLUE: IN GREEN 1000 TOP COIL - OUT BLUE 750 BOTTOM COIL.

    POSITION #2 BRIDGE GREEN/RED: IN GREEN 1000 TOP COIL - OUT RED 500 BOTTOM COIL ~ NECK RED/GREEN: IN RED 500 TOP COIL - OUT GREEN 1000 BOTTOM COIL

    POSITION #3 BRIDGE BLUE/GREEN: IN BLUE 750 TOP COIL - OUT GREEN 1000 BOTTOM COIL ~ NECK BLUE/RED: IN BLUE 750 TOP COIL - OUT RED 500 BOTTOM COIL

    When pictured as I did ruff in the drawing below the relative size of over-laying coils and their positions bridge/neck light a bulb in my head. In particular the Position #1 Neck GREEN/TOP coil over BLUE/BOTTOM coil. I immediately recognized that this was the heavy "full bass" setting I had loved so much. My other two "middle" settings could be any combination of the remaining. And the OUT-OF-PHASE any of the sets. Imagine however all of these could be had IN and OUT of PHASE with the 2 pickups that's a whole lot of love. I hope my pix post below.

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    Last edited by DeepFrequency; 04-20-2020 at 10:44 PM.

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    Last edited by DeepFrequency; 04-21-2020 at 02:01 AM.

  19. #124
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    Quote Originally Posted by DeepFrequency View Post
    Earlier in this thread the Les Paul low-z pickup (just one) was determined to be about 10ohms. Times 50: 500ohms or .5K Pot. is that correct per your formula? The schematic posted for two of these pickups is 2.5K. All help appreciate here as this is not my field. Would applying the guitar notion that if you had 250K pots but wanted more control use 500K pots work as well here? i.e. a 2.5K pot to a 5K pot? I ask because I have 5K pots and can't find the lower value.
    Consider the total load on the pickup that includes the volume pot or pots values when used in parallel with the actual amplifier input impedance. Most guitar amps have a 1M input impedance so the total load on a Fender pickup is 250K pot in parallel with 1M ohm amp input impedance. This turns out to be R1 times R2 divided by R1 plus R2 or 200K total load of parallel resistance. Now, low impedance XLR inputs have about a 2400 ohm actual input impedance to be about 10 times higher than the actual output impedance of low Z mics or guitar pickups usually rated at 150 ohms, called nominal rating, but many go as high as 300 ohms actual mic impedance. If you use a 2.5K ohm pot that is in parallel with 2400 ohm XLR input impedance you will have an actual load of about 1.25K ohms.

    Here is a quick test you can do to see how the pot loads the pickup output level. Use two alligator clip wires and play a note or chord and the alligator clip the end lugs of the pot across the pickup output and listen for any signal loss. Once the pot is installed, if the pot value is too high you may not have a smooth and continuous volume control adjustment. I would say that a pot value between 1K and 2.5K should get you in the neighborhood of the proper value for your 10 ohm pickup. Remember also that when two 2.5K pots are in parallel their combined value is 1.25K but also in parallel with the XLR input impedance of 2400 ohms. Try the 2.5K ohm or the 5K ohm pots and let your ear be the judge.

    I hope this helps? Let us know what you try.

    Joseph J. Rogowski

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    Last edited by bbsailor; 04-20-2020 at 11:35 PM.

  20. #125
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    Quote Originally Posted by bbsailor View Post
    Consider the total load on the pickup that includes the volume pot or pots values when used in parallel with the actual amplifier input impedance. Most guitar amps have a 1M input impedance so the total load on a Fender pickup is 250K pot in parallel with 1M ohm amp input impedance. This turns out to be R1 times R2 divided by R1 plus R2 or 200K total load of parallel resistance. Now, low impedance XLR inputs have about a 2400 ohm actual input impedance to be about 10 times higher than the actual output impedance of low Z mics or guitar pickups usually rated at 150 ohms, called nominal rating, but many go as high as 300 ohms actual mic impedance. If you use a 2.5K ohm pot that is in parallel with 2400 ohm XLR input impedance you will have an actual load of about 1.25K ohms.

    Here is a quick test you can do to see how the pot loads the pickup output level. Use two alligator clip wires and play a note or chord and the alligator clip the end lugs of the pot across the pickup output and listen for any signal loss. Once the pot is installed, if the pot value is too high you may not have a smooth and continuous volume control adjustment. I would say that a pot value between 1K and 2.5K should get you in the neighborhood of the proper value for your 10 ohm pickup. Remember also that when two 2.5K pots are in parallel their combined value is 1.25K but also in parallel with the XLR input impedance of 2400 ohms. Try the 2.5K ohm or the 5K ohm pots and let your ear be the judge.

    I hope this helps? Let us know what you try.

    Joseph J. Rogowski
    Big help, even with the parts that are over my head. I do grok the gist of what we are driving at. I really do appreciate your interest and help with this. I also notice we are both "ski's". To add my small understanding of electrics, would the pots wired in series add vs half the value? I made a speaker cab and ran into this ohms there.

    EDIT: to add to the complete picture here when I use this rig I always use a small ac powered mixer. The stereo 1/4" jacks into the two inputs of the mixer and a single line out to my amp. Why, because this gives me better volume control over the two mis-matched pickups and my present (and many new small bass amps) amp has only one input.

    EDITagain: rereading your post I am seeing XLR Low-z INPUT....there is no Low-z INPUT in my rig...I use an inline transformer to change the Low-z at the end of my cable to 1/4" input High-z. I used to have an amp with a built in low-z transformer to the 2nd channel, but sold it off years ago.

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    Last edited by DeepFrequency; 04-21-2020 at 01:58 AM.

  21. #126
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    There is a bit more to this. First consider a standard high impedance pickup. The impedance is only approximately equal to the coil resistance at very low frequencies. As the frequency increases it becomes inductive, rising in frequency, due to the coil inductance, and then the impedance maximizes at the frequency of the resonance composed of the coil inductance and the capacitance, cable and coil. The volume pot affects the Q of the resonance, that is, the width of the peak in frequency response. But also so does the tone pot since it must be considered as part of the load. (The tone capacitor has a low impedance at the resonant frequency and so it can be represented as a short at the resonant frequency.) That is, the resistance of the tone pot needs to be put in parallel with the rest. For a low impedance pickup, you would have to look carefully at the tone circuit, if any, to figure out how to compute the load.

    Quote Originally Posted by bbsailor View Post
    Consider the total load on the pickup that includes the volume pot or pots values when used in parallel with the actual amplifier input impedance. Most guitar amps have a 1M input impedance so the total load on a Fender pickup is 250K pot in parallel with 1M ohm amp input impedance. This turns out to be R1 times R2 divided by R1 plus R2 or 200K total load of parallel resistance. Now, low impedance XLR inputs have about a 2400 ohm actual input impedance to be about 10 times higher than the actual output impedance of low Z mics or guitar pickups usually rated at 150 ohms, called nominal rating, but many go as high as 300 ohms actual mic impedance. If you use a 2.5K ohm pot that is in parallel with 2400 ohm XLR input impedance you will have an actual load of about 1.25K ohms.

    Here is a quick test you can do to see how the pot loads the pickup output level. Use two alligator clip wires and play a note or chord and the alligator clip the end lugs of the pot across the pickup output and listen for any signal loss. Once the pot is installed, if the pot value is too high you may not have a smooth and continuous volume control adjustment. I would say that a pot value between 1K and 2.5K should get you in the neighborhood of the proper value for your 10 ohm pickup. Remember also that when two 2.5K pots are in parallel their combined value is 1.25K but also in parallel with the XLR input impedance of 2400 ohms. Try the 2.5K ohm or the 5K ohm pots and let your ear be the judge.

    I hope this helps? Let us know what you try.

    Joseph J. Rogowski

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  22. #127
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    Quote Originally Posted by Mike Sulzer View Post
    There is a bit more to this. First consider a standard high impedance pickup. The impedance is only approximately equal to the coil resistance at very low frequencies. As the frequency increases it becomes inductive, rising in frequency, due to the coil inductance, and then the impedance maximizes at the frequency of the resonance composed of the coil inductance and the capacitance, cable and coil. The volume pot affects the Q of the resonance, that is, the width of the peak in frequency response. But also so does the tone pot since it must be considered as part of the load. (The tone capacitor has a low impedance at the resonant frequency and so it can be represented as a short at the resonant frequency.) That is, the resistance of the tone pot needs to be put in parallel with the rest. For a low impedance pickup, you would have to look carefully at the tone circuit, if any, to figure out how to compute the load.
    Wow, you guys are good. I serious did not understand a single word of what you said. Alex Dumble the fellow who put in this mod and who is supposedly world famous now understands this physics but I am lost. The odd part in this is for a fact Dumble left in the 250K original Gibson pots. They were 1967, marked so, and added value to the bass. He even replaced one with a 1969 pot to keep it close to the original date. That pot was in the low-z circuit.And it sounded gang busters. attached is the drawing I have come up with from the Gibson Ripper source which had the 4 position switch and the in-phase/out-phase, something I know Alex had as my positions 3-4. Together with the 500/750/1000 tap information I got here, and the combination of those that Gibson put in the Les Paul Recording bass I pieced together this. NOTE: The Gibson Humbucker (Gold color) is copied from my guitar, it is what Alex Dumble installed and has not been altered. Wish I had done the same with the low-z.

    If curious minds what to see; Zip file is photos of my bass.



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  23. #128
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    Success !!! Alex Dumble your imagination has come to life again. One day to clean all the old pots an re-wire the Humbucker circuit with a new On-On switch for that cuts the Gibson choke in and out. That was great, and the Humbucker sounds great again, with an .047 orange drop cap.

    DAY TWO: With the all the parts and push-back wire in hand I solder up the 3 pole/4 position rotary switch to my diagram. Months of planning an years of waiting have all been worth it. I my plug 1967 Gibson EB-3 Alex Dumble Modified 1974 via it's XLR stereo jack to Y split to 1/4" plugs, to in-line Low-Z to High-Z transformer on 1/4" plug #1 and into 4 channel mixer channels 1 & 2. Out of the mixer/ Into my TC Electronics BH800 an VOILA!! Sound, Sound and More Sound. All 4 positions work....and with a few minutes of alligator clipping in a selection of different caps...lo and behold the Gibson schematic 4.7uf cap is the best. And the Kemet Aluminum Electrolytic 35v/4.7uf capacitor is the best sounding of the bunch. I want to thank everyone here on this thread for helping me complete this project. Perhaps one day you will hear this amazing sounding bass on a record somewhere.

    P.S. the cool sound this bass gets is the combination of the very clean neck low-z pickup....which today I am leaning towards the cleanest #3 parallel position mixed together withe the Humbucker, choke on, .47uf orange drop tone turned a little bit in. I have La Bella "DeepTalkin'" Flatwound strings and run it all thru the mixer an TC Electronics BH800 and a 10" kevlar speaker in a Trace-Elliot BLX-80. It used to be an Ampeg B-15, with an Electro-Voice 15". The Trace-Elliot sounds better, a very tight speaker. The BH800 has the tone bumped just a little on the mid, mid-high, and high. Jack Bruce would have loved this little ax and rig.
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    Last edited by DeepFrequency; 05-13-2020 at 03:23 AM. Reason: correct drawing

  24. #129
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    Quote Originally Posted by DeepFrequency View Post
    Success !!! Alex Dumble your imagination has come to life again.

    P.S. the cool sound this bass gets is the combination of the very clean neck low-z pickup.. Jack Bruce would have loved this little ax and rig.
    The way this pickup is made there are TWO pickups stacked on top of each other, EACH of them with 3 taps Green/Blue/Red at 1500/750/500 (per entry found here in this thread). I had looked up how Gibson combined these in the Les Paul Studio/Recording bass. To make a visual reference I drew larger or smaller ovals and labeled them by color. Now that my pickup works I have a choice. At present it is in a fixed wiring state with the Green coil on top: Except Rotary Selector #2 then Red is the Top Coil pickup. AND Blue coil for ALL of the Bottom coil pickup choices on the Rotary selector. The Selector changes the two pickups from Series to Parallel or Series Out of Phase to In-Phase.

    China sent Mini-Slide switches, On-On, by mistake. I find they will fit inside the available space in the cavity with the pots and wire loom. So I can make a modification similar to an Active pickups slide switch choice of Mids/Mid-Highs. In the first drawing I thought to access All the Bottom coil choices. But upon hearing the #2 Rotary choice of Red over Blue, it is a very full and bassy sound, I thought the Green might be More bassy but I would not need that. So I am opting to choose One Top coil change - Blue/Red: and One Bottom coil change - Green/Blue. More choices I think would be redundant and there is only room for two switches anyway. Attached is the drawing of my proposed addition. Also my initial drawing of the Les Paul bass combination of pickups. What I did not know about the Les Paul is whether the pairs were in Parallel or series which makes quite a difference.



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