Has anyone converted their deep switch to a phase switch?

nmiller

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I just picked up a 1976 M-85, now my only Guild bass with the '70s humbuckers. Past experience says that I will never use the deep switch, but I do occasionally like the out-of-phase middle position on my 1970 JS-II when I want a deliberately funky, off-kilter sound. Has anyone installed a phase switch with these pickups? How did it sound?
 

fronobulax

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I'm confused. As the original owner of a 1971 JS II I know my wiring is stock and if it the PU selector is "out of phase" when both PUs are selected then I don't know what I am hearing. What I hear is additive overall, when the selector switches from one PU to two, and not the change in frequency "response' I expect from out of phase PUs. The Deep/Hard toggle is just that, a two position toggle. So would you mind telling what you do to get the "out of phase" tone and why you call it "out of phase" as opposed to something else?

That said, it should be obvious that I have not tried any mods. I did once experiment with alligator clips that (reversibly) took the Deep/Hard switch out of the circuit. My recollection is that the sound was louder but not enough of an improvement for me personally to make it permanent.
 

nmiller

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Am I correct in assuming that your bass has two Guild humbuckers? My JS-II has a Bi-Sonic and a Hagstrom humbucker, and they're definitely out of phase; the combined sound is very nasal and has low output. I think Guild stopped using this wiring when they switched to their own humbuckers since I've never encountered a post-1970 bass that has it. They did the same thing on guitars when they switched from mini-humbuckers to HB-1s; my 1969 M-75 was out of phase, but my 1972 M-75 is in-phase.
 

fronobulax

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That explains it. I have "symmetrical PUs." that were wired in phase at the factory. I also note with a more careful reading, after I understand that the JS is out of phase, that your question comes down to "does anyone have experience with a pair of the Guild humbuckers wired out of phase?" My answer is still No but I understand the question. Perhaps I am too naive but isn't just a matter of un-soldering and swapping two wires to run the experiment? Restore the original if you don't like it, otherwise figure out the wiring that will disable the deep/hard switch and allow you to use the toggle to make the PUs in phase or out?
 

nmiller

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I think it is a simple mod, but I'm not handy with a soldering iron so I was hoping to see if anyone had done it first.
 

fronobulax

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I think it is a simple mod, but I'm not handy with a soldering iron so I was hoping to see if anyone had done it first.

OK. I have never tried it and I have never heard of anyone who has. Maybe buy a bass effects box? :)
 

Happy Face

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I have to get around trying that on my M-85 (Bisonics). Fits in with the timeframes mentioned above. Thanks for reminding me!
 

Happy Face

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OK. I brought my M-85 over to a talented friend's house. Yes, the pickups are out of phase. He noted that the Gibson ES 335 and 355s from that era were also wired that way. Why? We weren't sure. Maybe to get that ticcy-toc sound?

But ... he also cautioned me that it is not an easy fix. Forgive me folks, I did not understand all that he told me. But it had to do with the fact that if you reverse the wiring on a pup, the ground wire becomes "hot". He guessed that you'd enjoy more hum, until you touched the pickup ring or other parts. He also cautioned that the ground wires tend to be fragile little things, often the width of a hair! He once reversed the polarity on an ES 335 pup but we both agreed there's not enough reason to mess with an original Bisonic.

But he wants to confirm all of that so he kept the bass and will report in after he has done some snoopin' around.
 

Happy Face

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Apparently it is not as complex as first feared. Stay tuned for further progress reports.
 

mavuser

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Amazingly, I happen to own the very rare same exact 1970 JS II that NMiller owns, as well as the same exact 1968/69 SF II bass w Bisonics that he recently sold (as well as the same exact 1957/58 66J amp- all 3 identical to yours- amazing!)

yes the JS II and SF II basses I own are wired out of phase.


the reason 2 Bisonics are wired for reverse polarity and 2 humbuckers are not is quite simple...Bisonics are single coils. In certain situations they can and will "hum" or "buzz" on their own in neck or bridge, or together in middle, but with reverse polarity, in the middle position with both pickups engaged all or the majority of the humming/buzzing should be gone. It is a safety net for performing. The tone of the individual pickups should not change (although I am not here to debate that) and I'm not sure how much the "reversed polarity middle position tone" changes...but the hum should be gone in the middle position if done right.

The reason humbuckers are not wired for reverse polarity, is because the inherent nature and purpose of a 2-coil Humbucker is to "buck the hum," hence the reason humbuckers don't hum at all (or shouldn't) on their own or in any configuration. Therefore, reverse polarity is not necessary, and middle position output is not lost.

In the case of NMillers JSII (of which I own the identical bass), one pickup is single coil (neck), and one is Humbucker (bridge). So no hum in the bridge whatsoever. Now with reverse polarity, the middle position gives a second "no hum option." Also, this particular configuration was quite rare and transitional, they may have simply been following the "double Bisonic formula" for this small batch of Bisonic/Humbucker basses.

not to say the Bisonic on its own has any issues or hums at all- this will vary room to room and depends on outlets/wiring/grounding/dimmers/switches etc...

so in conclusion, yes Happy Face your M-85 II with 2 bisonics should be reverse polarity, as you recently found out it is. I don't understand why you would want to "un-reverse" the polarity. I suggest to leave it the way it is, unless I've missed something here, or elsewhere.

reverse polarity is very popular with telecaster guitars for the reasons described above. Many teles, or most teles, are wired that way by Fender at the factory from day one, at least in recent years.
 
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nmiller

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In certain situations they can and will "hum" or "buzz" on their own in neck or bridge, or together in middle, but with reverse polarity, in the middle position with both pickups engaged all or the majority of the humming/buzzing should be gone. It is a safety net for performing. The tone of the individual pickups should not change (although I am not here to debate that) and I'm not sure how much the "reversed polarity middle position tone" changes...but the hum should be gone in the middle position if done right.

This could be done without having the pickups out of phase, however. If they're wound in opposite directions and the magnetic polarities are opposite, they will cancel out the hum when wired in phase. This is how most humbuckers work (such as HB-1s). When combining a single coil and humbucker, it's impossible to truly cancel out the hum; with an odd number of coils, the background noise from one coil will always be present to some degree, so the middle position on our JS-IIs is not hum-cancelling.

I don't understand why you would want to "un-reverse" the polarity. I suggest to leave it the way it is, unless I've missed something here, or elsewhere.

Because the pickups are out of phase, it's not just noise that gets cancelled; a lot of the string vibrations get cancelled, too, so you end up with a thin sound and weak output. It would be nice to get a regular, in-phase sound out of the pickups as well, even if there's hum with it.

In the case of my bass - with two humbuckers - I want the extra flexibility of getting that thin sound at the flick of a switch.
 

mavuser

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I may have misunderstood what Happy Face wants to do, I've never been entirely sure what a "phase switch" does other than somehow change the tone of the pickups. I believe that is what is on my 2014 GSR M-85 II bass with Newark Street/Bisonic reissues (although it is advertised as a "bass roll off switch, the instrument was not built to all advertised specs).... I do not know that this somehow creates "reverse polarity" *or* if the 2014 GSR M-85 II was wired with reverse polarity separate from having a "phase switch" (Or whatever the switch is). My guess is that it is...but again, I lack understanding of exactly what a phase switch is doing. However, an S-100 guitar has a phase switch with 2 humbuckers, where reverse polarity should not be necessary to reduce unwanted noise

i made this post prior to reading NMillers above...thanks I need to read that a couple more times ha
 
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SFIV1967

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From here:
"Humbucking Pickup Out Of Phase With Itself
The closer 2 coils are to one another, the greater the cancelations will be when they go "out of phase". So, wiring a humbucker out of phase with itself is going to produce a lot of cancelations, a huge reduction in volume and a very thin sound. If that's not enough, the pickup will not be humbucking either. Still there are some people that like this kind of sound. The best way to put a humbucker out of phase with itself is to wire the coils out of phase in series.
Just to make sure we "cover all the bases", it is possible to wire a humbucker out of phase with itself in parallel. This produces the thinnest, lowest output of all possible phasing combinations. Still, for those that want to give this a try here is the wiring diagram."
Ralf
 

Happy Face

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One Bisonic on my M-85 will be reversed so they both are in phase. No switch will be added. There isn't one.

I really like being able to set the tones on two pups pretty different and then being able to alter my tone on the fly by simply changing the volume on the neck pickup. That's how my JS-II was wired when the Darkstars went in. I'm willing to deal with hum to have this option.

I've played Ricks for 40 years and learned to cope with hum. Like by turning off beer signs. Or using one pickup and turning the other down all the way.

Anyway, I'll see how it sounds. It is reversible.
 
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mavuser

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Because the pickups are out of phase, it's not just noise that gets cancelled; a lot of the string vibrations get cancelled, too, so you end up with a thin sound and weak output. It would be nice to get a regular, in-phase sound out of the pickups as well, even if there's hum with it.

Understood, thanks...you are only referring to the middle position with both pickups, correct?
 

mavuser

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This could be done without having the pickups out of phase, however. If they're wound in opposite directions and the magnetic polarities are opposite, they will cancel out the hum when wired in phase. This is how most humbuckers work (such as HB-1s)

Ok thank you I am now starting to fully understand something I havnt been able to grasp for a while. So the bisonics themselves are not wound for opposite polarity, they are however wired out of phase with each other. Have to say I don't have any hum issue with any of my guilds but I don't play at loud/gig volumes. My one 68 SF II bass w Bisonics sounds incredible with just the neck or just the bridge pickup, but is a little thin in the middle position with noticeably lower output. I don't think id ever mess with it but I do get some different tones using just one pickup, but moving my fingers on my right hand up/down the strings. I also have a SF I bass with just the neck Bisonic, and again just by moving my right hand up the strings, can definitely get some cool bridge/middle type tones- from the neck pickup. The JS II sounds super cool in the middle position. at least to me, even if the output is slightly reduced. I like that bass a lot
 

bklynbass

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I believe you are correct, mavuser. One improvement that Fred made with Darkstars was offering them in RWRP (reverse wound / reverse polarity) sets so they would hum cancel when in phase. Since the original bionics were all wound the same way they had to be wired out of phase in order to hum cancel. Since I never found any use for that nasal sound, hum cancelled or not, I reversed the phase on one of the pickups on my 68 Starfire II so they're now in phase and since then it has a much more useful range of tones.
 
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mavuser

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I believe you are correct, mavuser. One improvement that Fred made with Darkstars was offering them in RWRP (reverse wound / reverse polarity) sets so they would hum cancel when in phase. Since the original bionics were all wound the same way they had to be wired out of phase in order to hum cancel. Since I never found any use for that nasal sound, hum cancelled or not, I reversed the phase on one of the pickups on my 68 Starfire II so they're now in phase and since then it has a much more useful range of tones.

Thanks very much for this additional info. Starting to think maybe I should flip the neck pickups to make them in phase with the bridge pickups. I could imagine if they were both goin full throttle in the middle position, with both tone and vol knobs that you could achieve a wide array of tones. Until now I have simply accepted the Bisonic for what it is, on its own, without using 2 together. On the JS bass the blend of the Bisonic and Humbucker in the middle is a cool funky tone out of phase, but output is noticably lower. I wonder if putting those pickups in phase would create a lot more of an already good thing.

Correction: I went back to my SF II bass to really nut this out, and it is different than how I remembered (because I really just play the neck pickup on these)...in the middle position the SF II bass sounds quite good, like a solid blend of the 2 pickups, and no real noticable loss of output. however, with the "suck switch" engaged in the middle position, that is where it sounds more like its out of phase than "sucking." I was told when I got it the choke/transformer "sucker" had been bypassed, but I noticed the suck switch still did something, but the effect is primarily in the middle postion, not the neck or bridge. Thus, I am wondering if the suck switch was converted to phase switch before I got it. Im really not sure but it sounds real nice without the suck switch engaged!

one other odd thing though, in the middle postion, either/both volumes control both pickups. so if both vols are on 10 and I turn one down to 0-2 range it kills the volume of both pickups (without the suck switch)...
 
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mavuser

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if 2 Bisonics are out of phase with each other, one would appear to be upside down, which you could easily see just by looking at the bass, correct?

Also, a phase switch would only alter the sound in the middle position, correct?
 

nmiller

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The phase is due purely to the way in which the pickups are wired together; turning them around physically has no effect. But yes, the sound is only altered in the middle position.
 
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