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Post by asmith on Dec 31, 2010 11:52:02 GMT -5
All these threads make me look like I'm seeking attention through guitar wiring. I'm going to have to start giving back as much as I'm getting. Or see a shrink. Or both. A friend of mine has a Gibson Les Paul. I mentioned that I was in the process of shielding and rewiring my Strat, as well as designing a two-humbucker 'dream scheme.'Of course, he wanted in on the action. "You mean I can have more options on my guitar, and still maintain a stock appearance?" "Of course. Have you heard of Jimmy Page?" "Have I?!" And so it went on. What's great about this mod, and I would hope somewhat relieving for you guys, is that whilst I haven't got the capacitors or shielding done for my Strat yet, whilst I haven't even built the Frankenswitchocaster, all Paul needs to do is get some 22 gauge wire and four long-shaft push-pull 500k pots and he's in business. (It's not lost on him that his name's Paul and he owns a Les Paul.) Now the classic 'Jimmy Page' mod is all well and good, but we want series/parallel options for the Bridge pickup, moving the coil-cut option to one push/pull. This is pretty much Deaf Eddie's version of the Jimmy Page mod. So, for clarification, Paul wants a push/pull ('PP') to put the bridge coils in parallel, a PP to split both humbuckers to single coils, a PP to put the neck out of phase, and a PP to put the Bridge and Neck pickups in series with each other. Jimmy Page's illegitimate rock-n-roll guitar-wiring lovechild. But wouldn't it be great if we could cut different pickups depending on series/parallel mode? If we're in standard series mode for the Bridge pickup, we can cut the innermost coil, but if we're in parallel mode, we cut the outermost coil.I've drafted up a diagram and tested the routes out of one such arrangement. The asterisked half of the coil-cutting DPDT switch is where the coil-cut for the Neck pickup will go. Here's a tabulated layout of the different signal paths depending on how the switches are configured. The only real trouble with this switch arrangement is that the direction of the coil cut depends on which mode you're in. If you look at the signal path diagrams, you can see the coil-cut occurs when the switch is pulled in 'series mode,' but occurs when the switch is pushed in 'parallel mode.' Does anybody have any bright ideas for coil cutting on the same direction?As always, everybody's help is gratefully appreciated. Thanks. Al.
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Post by newey on Dec 31, 2010 12:43:33 GMT -5
I didn't get a chance to check the diagram, but have you considered that, by selecting the outermost coils in parallel and innermost in series, you may not achieve hum-cancelling, depending on the pickups used? Both may be humcanceling, or neither may be, but check the coils first. I assume you've seen JohnH's JP mod? Not what you're looking to do, but read what John has to say about control functioning.
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Post by wolf on Dec 31, 2010 14:29:29 GMT -5
asmithYes, the Jimmy Page Wiring is one of the most popular guitar modifications on the Internet. Not that you needed another link, but here is my explanation / diagram of it: www.1728.com/guitar9.htm
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Post by JohnH on Dec 31, 2010 15:47:25 GMT -5
Does anybody have any bright ideas for coil cutting on the same direction?As always, everybody's help is gratefully appreciated. Thanks. Al. How about like this: Also, theres a few other ideas that you might be interested in: Borsanova shuffled the switches slightly so that the bridge pup changes from local series to parallel instead of coil cut, and gets its coil cut when you also cut the neck pup: guitarnuts2.proboards.com/index.cgi?board=nutzoid&action=display&thread=3772&page=2I chipped in with a new wiring diagram for it, and the last version of that is reply 25. Raz59 and 4real have built this one recently. When it came to rewire my own Gibbo LP however, I chickened out of putting in all those PP pots. I really like the firm simple action of a standard pot. So I have built a design that gets the coil cuts without changing pots, using the tone controls, and I put my S/P and phase switches on the back of the switch cover. This one is still my favorite LP wiring: guitarnuts2.proboards.com/index.cgi?board=schem&action=display&thread=4571It has a basic cavity wire up, then a range of interchageable switch options - of which the most basic (coil cuts only) has no new parts needed. cheers john
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Post by asmith on Jan 1, 2011 10:25:39 GMT -5
Newey,
I had, but it had slipped from memory. As had Borsanovas Twenty-Dual Mix, which is looking like the way forward! Thanks mate. The fundamental ethos of the two-switch design I had up there in Post #1 was to change the function of certain switches depending on the state of other switches, allowing for more options; Borsanova's scheme achieves that perfectly. Paul's really digging the availability of all those sounds.
Whilst B's scheme allows which neck coil to select in single mode, I'm confident - or at least thinking I might as well give it a shot - that a little brain-work on a grey January day should be able to tinker with the diagram so that the Neck pickup can switch between series and parallel, instead of the Bridge pickup, whilst keeping everything else the same. Then we can simply swap the words 'Neck' and 'Bridge' on the diagram and we're set to go.
Wolf, cheers for the head's-up. Reversing the wiring might be a very good idea, I'll have to look further into it - depends whether Paul's likely to be playing Single Neck and Bridge Outermost, or Single Neck and Bridge Innermost more often.
John, thank you for your input - as ever your knowledge has an uncanny tendency to make me slap my forehead and wonder why I never thought of such and such.
Let the parts ordering begin.
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Post by asmith on Jan 3, 2011 21:56:21 GMT -5
Usually, I wouldn't double post, I'd edit my previous post. But I think this 'new' development deserves a separate post. Instead of the changed Twenty-Dual Mix, we're just going to use the original one, but I'm going to swap some volume control lugs around. In Bors's 'Mix' scheme, the Neck volume is bypassed in series mode, but we want it to work. Bridge volume works as a Bridge 'bypass' still, as in the 'original' scheme. I've got a signal route for this that ought to work. The only drawback is it'll result in 'volume coupling' on the use of the Neck volume in parallel mode, but to be fair Paul's so used to the 'standard' Gibson wiring he'll live with it. Fine and dandy. The Broadbucker configuration's really looking like a nice idea as well - for the ones hopefully learning from this post, the Broadbucker concept is explained on the diagram in the link above, next to the 'BV.' Here's Newey re-posting Borsanova getting excited about it and explaining the concept.This is where the problem occurs. In Borsanova's original scheme, the signal path is Ground -> Neck Pickup -> Neck Volume & Tone -> Series Connection -> Bridge Pickup -> Bridge Volume & Tone -> HotThe idea as sketched out numerous times being that if you turn down the Neck Tone, the Bridge trebles bypass the Neck pickup and go straight to hot. Surely that's wrong?! In that signal path, turning down the Neck Tone would send the trebles from the Neck back to ground, effectively shorting them on the Neck pickup, leaving the Bridge pickup's full output in series heading off to the amp. To achieve the Broadbucker configuration, you'd have to go: Ground -> Bridge Pickup -> Bridge Volume & Tone -> Series Connection -> Neck Pickup -> Neck Volume & Tone -> HotThat way when you put the Neck tone to zero, it acts as an open gate for the trebles from the Bridge pickup to hit the Series Connection, run through to the Neck Volume & Tone and then to Hot. I realise that guitar circuitry is based upon alternating current so that essentially the signal is 'traveling both ways.' I realise that in some cases this stuff has been built. But am I wrong, or do I need to go ahead and change the series wiring?
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Post by JohnH on Jan 4, 2011 6:07:57 GMT -5
I think its very good to keep both volume controls active in series mode, including when out of phase. There are many variations of tone as you sweep the controls and blending using the the knobs can function more smoothly than in parallel. Mu belief is that it does not matter tonaly, what order the -pickups are connected, ground=neck-bridge-hot, or the other way around. There are electrical theories to confirm this.
Good luck with your design
John
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Post by asmith on Jan 4, 2011 7:57:19 GMT -5
Last night, I wrote that previous post, racked my brains some more, turned off the computer and went to bed. As my head hit the pillow, I closed my eyes and thought: "Of course it works both ways you pillock." Cheers John. There's volume coupling in parallel mode, as per usual Gibson. In series mode you can turn down either pickup and the other will still be on. Bingo.
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Post by sumgai on Jan 4, 2011 14:21:22 GMT -5
Both a' ya's..... Yes, electrically the two arrangements are the same, but..... ChrisK was the first (that I know of) to propound this theory. His thinking was that if you shunt out some of the Neck's highs, leaving the low tones, then add that remainder to the Bridge's signal, you end up with an overall brighter tone, with a fuller bottom end. Doing that in reverse (shunt the Bridge highs to ground) sort of defeats the purpose of this particular scheme. Sonically speaking, of course. The real theory behind this is that two coils in series add their inductance values, and thus act to suppress the higher frequencies. By killing off some of those highs first (via the shunting trick), the remaining ones are not so strongly affected by the series-connected coil, i.e. they tend to remain at nearly full strength, comparatively speaking. It should be Q.E.D. that the Bridge's highs are going to be more desirable, tone-wise, than those of the Neck. I wouldn't put it past Chris to have dreamt this up first, but in point of fact, it's the exact scenario that Fender used in their S1 schema for the Deluxe series (guitars and basses) in 2004-2007. Chris liked it, I didn't - I removed mine almost immediately. But as they say, different folks for different strokes. HTH sumgai
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Post by sumgai on Jan 4, 2011 14:32:03 GMT -5
(It's not lost on him that his name's Paul and he owns a Les Paul.) I don't have a TV, haven't had one for more than 40 years, but.... On occasion, at a friend's house, or in a bar somewhere, I'll look at the boob toob from time to time. One my favorite commercials in recent years was for Coors. The devilish smile a L.P.'s face tells us that he could've been a good actor, but the look on the kid's face, that's priceless! ;D
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Post by JohnH on Jan 4, 2011 16:02:42 GMT -5
asmith - schematic looks fine to me! Now you get to figure out exactly which coils you want your coil cuts to switch to and what the relavent wire colours are. On each pup, is it the adjustable or the screw coil? nearer the bridge or neaer the neck? Will you cut to a north coil on one pup and a south on the other? - making sure its all in phase when it should be. Depending on how the pups are currently confgured, you may or may not be able to make all those choices at once, unless you also consider flipping a magnet, or are happy to pick which neck coil is cut to to make the rest optimised. On an uncovered neck pup, I think both coils sound pretty much the same, but if it is covered, then the screw coil is the clearer one (at least on my LP with '57 classic neck pup). Tests with multimeter and screwdriver pull-off tests are the key to figuring this out, even if you think you know what pups you have. this may help: guitarnuts2.proboards.com/index.cgi?board=reference&action=display&thread=4938Also, you can work out the magnetic polarity using a compass, to see if both screw coils are the same polarity or different. Or, you can place the two pups face to face and see if screw coils attract or repel. John
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Post by ashcatlt on Jan 4, 2011 17:35:01 GMT -5
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Post by asmith on Jan 4, 2011 18:24:35 GMT -5
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Post by JohnH on Jan 4, 2011 19:11:17 GMT -5
im sure this will be great, but when there is a choice of sounds that are very similar, and one is lower noise than the other, I think it is better to suppress the sub-optimal sounds, for the sake of playing simplicity. On these JP-type designs, it is perfectly possible to have all combos with no more than a single-coil amount of hum, and have all two-coil combos nominally humcancelling. It maybe just a symptom of obessive/complusive disorder, but its nice to have it all as optimal as possible. There will be hum to some extent, due to unbalanced coils, but no more than minimum.
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Post by asmith on Jan 4, 2011 19:34:42 GMT -5
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Post by asmith on Mar 9, 2011 15:36:57 GMT -5
After postage delays and only soldering when really available, we have a sort-of finished model. But there's some kinks that need working out. (Kinks jokes here please) We have a Seymour Duncan 59 Model as the neck pickup, and a Custom 5 in the bridge. The screw coils are towards the bridge, the slug coils towards the neck, which is how we wanted it. The pickups are uncovered, so as far as I know - which isn't particularly far - it shouldn't make a difference to the sound, but I'm including that tidbit of information in case it does. Either way, the "Seymour Duncan" text on the bridge pickup is right-way-up if the guitar rests on a stand, like this, and I think Paul is more of a sucker for that than he'd like to admit. This was my first solder-fest in a long time. I expected problems along the way. More solder was used than I'd like - [url=http://www.google.co.uk/search?q=smug+t t]I'm only super accurate on the fretboard, ho ho ho[/url]. Common sense tells me I ought to have 'built up' to so complex a mod, but I'm not an electrical engineer first, I'm a guitarist. After using the screwdriver test, the push/pull pots mostly do as they should to pickup selections. More on that mostly later on in this post. The first issue we have is that I accidentally wired both the pickups 'backwards.' When selecting the single coils, the scheme selects the screw coil on the neck pickup and the slug coil on the bridge pickup - namely, the inner coils. We wanted the outer coils, to give more accentuated sounds. That's easily fixable with another afternoon of soldering. The second issue is that I wired the Bridge Tone Control backwards. I don't know how I did this, but I know that I constantly have a tendency to double and triple-check everything, give myself the green light, and proceed to bugger up something without fail. So, this isn't unexpected. The Neck Tone Control just doesn't seem to work. I'm suspecting a short circuit from a too-large glob of solder. Hopefully a quick fix. The pickups being in and out of phase is very difficult to tell apart, so much so it might be my brain playing tricks on me that there is even a difference. I'm going to see if there's a short on one of the push/pull DPDT lugs from too much solder or something. The thing that bugs me the most, and what I'd like the most feedback from here please, is that when playing, a note seems to come through the amp like so: noteNOTEInstead of: NOTEA symptom of a problem with the guitar wiring? The obvious way to check is to try the guitar with another amp - that'll be another week until we can get the guitar into another amp. Hence my request. I realise most of this post comes across as a needless update that says rather pointlessly, "I'm not finished yet." I'm hoping one of the gurus here can read over my problems and say, "Have you thought that it might be this?" That has the potential to save me afternoons of frustration. Gracias amigos.
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Post by newey on Mar 9, 2011 22:08:56 GMT -5
I'm not sure I have any brilliant insights here (or anywhere else, for that matter . . .). But the first thing that popped into my head when I read about it was "lower the pickups". Don't know if you've done that yet, but all sorts of weirdness can ensue if they're too close. Other than that, I got nothin' . . .
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Post by asmith on Mar 17, 2011 16:54:21 GMT -5
The problem was thus. I'd wired the neck volume and tone control like so: And the connection to ground, marked in red, was duff. So the volume control was just acting as a variable resistor in parallel with a cap that was in series with the tone control potentiometer. Thankfully I noticed it pretty quick. OoP works perfectly. Here's the thread with demonstrative sound samples.
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