otaku
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Post by otaku on Jul 17, 2007 23:40:21 GMT -5
Ok, here's the deal: I have an HSH guitar with a 3-way switch that selects each pickup, one at a time.
What I wanna do is to install a switch to change the humbuckers to be series/single/parallel. I know this can be done with a dpdt switch for one humbucker, but as I have 2, I should use a 4pdt.
The problem now is that I can't get a 4pdt switch over here (damn Argentina, the end of the world...) and I don't want to install 2 dpdt switches, as I have practically no place.
Is there ANY chance to be able to achieve this with a dpdt switch having in mind that all the pickups are active alone, and never combined?
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Post by JohnH on Jul 18, 2007 0:42:54 GMT -5
To do what you want, to get series/para/single options, switching 2 humbuckers at once, does indeed need a special 4PDT on-on-on switch. These can be obtained from US suppliers, but at considerable cost. If I was you, I'd just do series/single, for which you can do both pups with just a single, standard two position DPDT toggle.
cheers
John
John
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Post by sumgai on Jul 18, 2007 2:28:37 GMT -5
otaku, PM me your address, and I'll mail a 4PDT to ya. I presume that you'll be wanting the switch found in the top-center of the first diagram in Chris's Template Bank. Check out UnklMickey's Tutorial on Series/Parallel switching. Specifically, look near the bottom of that post, you'll see how to wire the above switch to implement your desired scheme - simply double up on what unk has drawn, and you should be all set. HTH sumgai
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otaku
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Post by otaku on Jul 18, 2007 6:21:42 GMT -5
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Post by michaelcbell on Jul 18, 2007 6:27:52 GMT -5
be careful, on/on/on doesn't always do what you're looking to do. I say this because there are two types of on/on/on switches, one that connects both sides to the center in the middle position, and one that connects only one side to the center in the middle position. You need the second type, which is less common. I'd take sumgai up on his offer.
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hugh
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Post by hugh on Jul 18, 2007 6:50:42 GMT -5
I don't see why he would want to connect only one side to center in the middle position. For series/split/parallel I though you used a regular 3 position switch? on/on/on
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Post by michaelcbell on Jul 18, 2007 9:29:08 GMT -5
picture it this way (I'd reference ChrisK's drawings, but photobucket is blocked at work, so I can't see them), the numbers are lugs of the switch. 1 4 2 5 3 6 'normal' on/on/on middle position connects 1,2,3 and 4,5,6 'special' on/on/on middle position connects 1,2 and 5,6, which opens up all sorts of new possibilities.
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Post by sumgai on Jul 18, 2007 12:35:03 GMT -5
hugh, michael's correct, it's the second choice that makes a S/s/P scheme possible. Witness the drawings in UnklMickeys post, cited above, they speak volumes that mere words can't match. otaku, Do you know for a fact that the DiMarzio switch you linked is the correct one? There's no technical detail explaining the internal switching arrangement, and that always makes me suspicious. And FWIW, that handle looks awful..... clunky. It appears to me like it belongs on a automobile dashboard, not on a guitar. Most guitars I've seen sport a much slimmer handle, like this one: Tell me, what do you think of this choice: WD Music - Kent Armstrong 4PDT? That's labeled specifically to do the job you're asking for, and it looks a lot better, IMO. ;D HTH sumgai
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Post by ChrisK on Jul 18, 2007 12:44:45 GMT -5
Yepper dooper! It is indeed the switch found in the top-center of the first diagram in that referenced Template Bank. (BTW, he added a new one for the import boxed lever switch.) It's that there; 4PDT ON-ON-ON (how most guitar (re)wirer's refer to it), or 4PDT Center-ON (the CORRECT(er) designation since there is also the 4PDT Center-OFF switch [except there is that low cost bastardization of the original LP switch that has both outside terminals connected to the middle common when in the middle [both] position, oh wait, it's actually a good optimization]), or 2P3T (the CORRECT appliance (as in sweeper or blender) usage nomenclature (I was gonna say handle but it already has one) since these are used (with an external jumper(s)) to select 2 poles of 1 of 3 things like motor windings. Since these switches have 4 discrete pole groups AND 3 discrete/ distinct toggle positions, I think that it should be called a 4P 3T Center-ON or 4P 3T ON-ON-ON. Actually, Center-ON is the best designation since the optimized LP-type switch only comes in a 1 pole configuration (it would be a 1P ON-BOTH-ON), and these switches only come in a 2 or 4 pole configuration. See switch templates. Using a designation scheme like xP3T Center-On may be redundant in that the Center-ON infers to a special 3rd or center/middle position, but if we could all agree on a clearer designation, we could eliminate all of the coming redundant explanation over the years...... No it isn't, check my switch template for its internal switching. [ Now, as for the Kent Armstrong hybrid DPDT Center-ON combined with a DPDT Center-OFF into a switch that only "looks" like a normal switch (caveat emptor), I propose that we call that the 4PKA switch.] I've been thinking of uses for it, but I haven't come up with $20 worth of them yet. The switching of a dual coil pickup from series to parallel requires two poles (two connections have to go two different places). Two humbuckers thence require 4 poles. The only way that these switches work is because the single mode is in the middle and these switches switch one thing at a time per two pole group. While the DiMarzio switch may look "clunky", the large bat IMHO often looks more at home scale-wise with traditional guitar knobs and such, and is more robust than the tiny mini-toggle. Even though you are only using one pickup at a time, the only way that you could use a DP3T Center-ON for the series/single/parallel function on both humbuckers would be if a Tele-type (shuddup) 2P3T lever switch was used for pickup selection alone (and then there would be some convoluted hanging coils aboot). I know exactly how to do this (inside-out he peered), but an aneurysm lurks darkly for the linear-minded whence exposed. Here's a cheaper excellent quality part ($17.51 quantity 1): www.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=M2044B2B1W01-RO-NDwww.nkkswitches.com/pdf/MtogglesBushing.pdf
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Post by michaelcbell on Jul 18, 2007 14:59:52 GMT -5
Wikipedia claims our DP(3)T on/off/on to be a "DPCO" en.wikipedia.org/wiki/Switch The issue with any of these names is translation. Is there a standard out there that would make easier finding these things to ACTUALLY PURCHASE them? My experience says no, but my experience is somewhat limited. Perhaps we only need to arrive at consensus for the special on/on/on we are speaking of here since the others (normal on/on/on and on/off/on) seem to be relatively rooted in the public psyche. Perhaps on/split/on?
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hugh
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Post by hugh on Jul 18, 2007 18:14:18 GMT -5
That would make sense. However, I'm sure there's a technical name for it somewhere.
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Post by michaelcbell on Jul 19, 2007 6:05:06 GMT -5
In my experience, there's no widely used moniker for this type of swtich - I usually have to search through the data sheets to find what I'm looking for. As I stated before, though, I've got limited experience purchasing these particular items.
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Post by sumgai on Jul 19, 2007 14:29:03 GMT -5
michael, et al, No, there's no "standards body"-approved name for what we're talking about. So far, this switch seems to be purpose-designed for the guitar world's needs, so it hasn't caused enough problem for the "big boys" to name it........ yet. Sadly, we can't drop the xPxT moniker altogether, we need to be able to distinguish just how many poles and how many positions are possible. (Remember Chris's mind-boggling rotary switches. ) The best way to denote what happens in the middle position of a toggle or slide switch is the x/y/z descriptor. Our "problem child" is indeed best described as a 4P3T on/split/on switch. These naming problems are rooted in history, much of which is now a century old. (!) I don't foresee that the dust will ever settle within my remaining years. I think it's good that we talk about this, but we can't forget that other websites out there will remain "unenlightened". We need to keep that in mind as we make recommendations to our new visitors/members. BTW, michael, I don't see DCPO as having anything to do with this arrangement, particularly not on that wiki page. A "center off" or a "change-over", neither of these are applicable here (except that "change-over" is universally applicable to every switch ever made!) Onwards...... Chris, I don't concur with your findings in re: Kent Armstrong. In point of fact, K.A. designed this switch for this job, for Brian May. Prior to that time, such a thing didn't exist in the mini-toggle world (or if it did, it was extremely well hidden from view). Both you and UnklMickey have posted about this switch, its history and its best uses in the Schematics sub-Forum (as have others). Further..... the DiMarzio switch presents no information, directly from their website or elsewhere, that would lead one to think "this is what Brian May used, therefore it's what I need". I believe that the leap of faith required to make that assumption is unwarranted. And at 30 USD, that's a pretty high leap...... Further, the spec sheet for the NKK switch you show (from DigiKey) is also unspecified for this job. The best I can get out of the various sections of the part number are that it can do a 4PDT, on/on/on, and that's it. How would one know that the center-on portion is split, like we need? That was the only reason I rejected DigiKey, Mouser, and a host of other suppliers - lack of specific details on the internal switching for the center position. To my mind, lacking such a diagram, the K.A. and/or B.M. designations will have to suffice as being what is needed. </morning rant> HTH sumgai
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otaku
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Post by otaku on Jul 19, 2007 16:31:42 GMT -5
Hi guys! Wow, I never thought that my question would lead to such interesting discussion Now lemme tell you, I had been doing some research on this topic about the 2 types of 4pdt switches that are indeed different in the center position, as michael described above. Thing is, the "guitar" type is the most common one. I even got some catalogs from switch manufacturers like ITT and checked their specs and all of their 4pdt switches connect pins 1-2 and 5-6 on the center position (check model number 7411 here for example: www.ittcannon.com/media/pdf/catalogs/Leaf/7000toggle.pdf. That's the one we're looking for right? Also while doing my research I got to this thread in the Parker Guitars Forum where they talk about this issue and one of the guys there mailed Dimarzio to ask them how their 4pdt switch behaves, it's an interesting read: www.parkerguitars.com/forum/topic.asp?TOPIC_ID=4486&whichpage=2But as I said before, the "guitar type" is the most common, so probably any 4pdt switch will work unless it's realy your unlucky day when you buy hehe. And last but not least, down here in Argentina there is no switch at all, any type. Just dpdt ones
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hugh
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Post by hugh on Jul 19, 2007 17:31:58 GMT -5
Interesting, I just received my 4P3T mini toggle from Mouser today. It's the NKK M-2044.
There are two pairs of poles that operate as you guys are describing... Poles 1&3 connect to top only in the center, and 2&4 connect to bottom only in the center. (you decide which way is up)
I thought it would be center ON, not Split. However, it will still work fine for what I need it to do.
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Post by ChrisK on Jul 19, 2007 18:58:18 GMT -5
The article indicates that a DPCO is DP Change Over. A change-over switch has a "resting position" in the middle (sort of like them Frankenstein DPDThroooooooww open frame knife switches. I agree with 4P3T on/split/on. Regarding the Kent Armstrong switch; I know that you don't, and you are correct. Unfortunately you may disagree for the wrong reason! He designed it for BM, but likely NOT for this job. He designed this switch (well, developed a custom contact switching scheme using PRE-EXISTING internal switch components) to consolidate the Brian May scheme into one switch per pickup. The BM scheme had a DPDT phase reversal switch and an effectively SPST for shunting (OFF) in a series pickup chain. This was possible because the split effect contact stampings existed already. This drawing shows how this switch was designed to be used. as labeled on the hand drawing, it is a DPDT Center-OFF and a DP3T ON/SPLIT/ON switch combined. My template exactly shows this. The DiMarzio switch is a proper 4P3T ON/SPLIT/ON. BTW, the DP3T ON/SPLIT/ON switching method for series/single/parallel has been around for some time. I've seen it in DiMarzio wiring instructions for some time. i37.photobucket.com/albums/e84/cekikta/Wiring/bluesbucker.jpgWhy you are correct (why the KA switch CAN be used for this job). In the normal usage of a DP3T ON/SPLIT/ON switch for series/single/parallel on a two coil pickup, since only one coil is selected in the middle position (why this switch even works for this function - one thing at a time/toggle please), only one switch pole need make contact in this position (SP3T Center-ON [somewhere]). The other switch pole can be SP3T Center-OFF since the unused coil is just hanging aboot (loitering). If the two poles of the DP3T ON/SPLIT/ON section are used to select the switched lead from the coils connected in the center single coil mode for both pickups (one pole each) AND if the two poles of the DP3T ON/OFF/ON section are used to select the switched lead from the coils NOT connected in the center single coil mode for both pickups (one pole each), the Kent Armstrong switch CAN be used for this dual function as well as the traditional 4P3T ON/SPLIT/ON under discussion. This came to me as I was peering "inside-out" the other day (why I can do this dual pickup switching with just one DP3T ON/SPLIT/ON switch if I can use both poles of the 2P3T lever switch for the "outside" stuff). I reiterate: since coils are hanging aboot anyway in any discussion in this post, if a real 2P3T switch is used for the primary pickup selector (neck/middle/bridge), then the series/single/parallel for both in unison CAN be implemented with just one DP3T ON/SPLIT/ON switch. Using a 3 pickup LP-style toggle switch will not work with just one DP3T ON/SPLIT/ON switch. otaku, what switch is in your guitar? I don't think that it is what BM used. www.dimarzio.com/media/pdfs/hardware.pdfM2044B2B1W01-RO-ND indicates as follows: page 3 of the data sheet link shows: M20 - switch series 4 - 4PDT or DP3T (since this refers to body size) 4 - ON/ON/ON or 3 On circuits (since no one can make up their mind on what to call this) page 4 of the data sheet link shows the contact switching logic (use the M2044 info). Specific is. Since there are many, many variations in each manufacturer's switch line, individual switch datasheets don't exist and only series data sheets do. I confess to having a distinct advantage in that I've been using this type of data sheet for over 30 years (OEM is). This template is pretty accurate... guitarnuts2.proboards45.com/index.cgi?board=schem&action=display&thread=1158705194In mini-toggle switches, I've never seen anything that maintained both outside contacts ON to the center pole contact, nor can I envision a mechanical swinging center pole contact structure that could. Anyway, this has been way too much fun, and we have all of the answers, anyway. This can be done with a 4P3T ON/SPLIT/ON switch or a 4P3T ON/KA/ON switch with any type of three pickup selector switch suitable for neck/middle/bridge (a.k.a. the Tele or original Strat switch, or the LP three pickup selector switch for example), or with a DP3T ON/SPLIT/ON using a dedicated (wire yer tone pots to the pickup input poles on the switch) 2P3T pickup selector switch (a.k.a. the Tele or original Strat switch). otaku, since you indicate that the 4P3T ON/SPLIT/ON DiMarzio switch is not available in Argentina, if the DP3T ON/SPLIT/ON switch IS available, let me know what other switch is in you guitar for pickup selection and, if conducive, I'll show you how to do this.
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otaku
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Post by otaku on Jul 19, 2007 21:00:44 GMT -5
Hi Chris, right now the guitar has a Dimarzio Superwitch installed, but I already bought a new Fender 3-way lever (the one the telecasters have) to simplify things. I don't want any "weird" or special connectios. Just 1 pickup at a time.
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Post by sumgai on Jul 20, 2007 4:39:24 GMT -5
Chris, I ascribed the 4P3T KA switch to him only in that he combined a pair of existing DP3T on/split/on switched into one body. I've always been under the impression that this is what B.M. was wanting, as is otaku - one switch for both pups. Am I wrong on that one? (Not a rhetorical question.) I missed Pg 4 of the datasheet, sorry! Mea culpa! Oh yes, done is. Even in the Re-done-dant Department of Re-done-dancies. ;D sumgai
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otaku
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Post by otaku on Jul 20, 2007 15:00:42 GMT -5
Exactly, one 3 position switch on/on/on (or whatever you wanna call it, on/split/on) for both humbuckers.
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Post by ChrisK on Jul 21, 2007 11:54:45 GMT -5
The design will use a 2P3T Tele-type (sorry, I miss 110 baud) pickup selector switch for bridge only/middle only/neck only and a DP3T ON/SPLIT/ON switch (6 terminals). I will post it when completed. KA combined a DPDT Center-OFF (6 terminals) and a DP3T ON/SPLIT/ON switch (6 terminals) to do the BM scheme for one pickup with one switch each (at least this is what the posted sketch shows). This is the BM "Red Special" wiring scheme. As I have shown in past posts, this BMay optimization does not require a KA switch, but only a "pedestrian" DP3T ON/SPLIT/ON switch (yes, and only ONE per pickup). guitarnuts2.proboards45.com/index.cgi?board=schem&action=display&thread=1168294514It can ALSO (as I have indicated) be used (probably inadvertantly) to do what otaku had asked for. These are my strong suspicions. I'm actually happier now since the KA switch is now known to be able to do TWO fairly big and complete things. Three, if I count its ability to eliminate shorted coils in my ToggleCaster design.
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hugh
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Post by hugh on Jul 21, 2007 11:57:01 GMT -5
What is the advantage of leaving the coils open?
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Post by ChrisK on Jul 21, 2007 12:18:38 GMT -5
There are those a'board that believe that shorting a coil causes a reduction in note sustain (me) since the vibrational energy in the strings is called on to develop an electrical output from each pickup into a load. When a coil is shorted, this load (for this pickup) which is normally in the area of 100K Ohms and up is now reduced to the output (self) impedance of the pickup. This is around 5K to 15K Ohms. More load dissipates more energy taken from said string(s).
There are folks that believe that a hanging coil (a coil connected with one wire to the output bus, but the other wire is not connected anywhere) will act as an antenna and induce noise into said output bus point. I tend to believe this only if a suitable AC path exists from the unconnected wire to wiring common.
I have a guitar wired in a particularly demented way that enables me to test both theories.
While I CAN hear a discernible difference in level and high frequencies since I can immediately switch a coil from open (with one end connected to common) to shorted (in both cases said coil is not contributing any output signal), I don't hear anything nearly as significant when I switch a coil from freely floating to having one end connected to the output bus.
I trust these results since each before and after test occurred on the same plucking of a given string. I don't trust the repeatability of tests that are A/B's on two sequential notes (different plucks).
These test went:
Pluck note,
Listen (on a PA system, remember, that there high frequency stuff is important),
A/B/A/B/A/B/A/B........ at about a 1 HZ rate,
Formulate opinions,
Search for windmills.
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Post by ChrisK on Jul 21, 2007 22:05:30 GMT -5
I also noted the logic for use with a traditional Fender 5way lever as well since, aside from the two extra detents (them notch positions), they are the same switch.
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otaku
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Post by otaku on Jul 22, 2007 1:54:43 GMT -5
Do you know in Dimarzio color codes, which wire is which?
I know greens are ground but the rest is a bit "difficult" to read with all having the same color.
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hugh
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Post by hugh on Jul 22, 2007 9:46:20 GMT -5
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otaku
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Post by otaku on Jul 22, 2007 16:23:46 GMT -5
Yes I know that, but which wire is which in the previous drawing chris did?
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Post by sumgai on Jul 23, 2007 3:12:54 GMT -5
Chris, Long story short..... It sounds like you're saying that a magnet depletes a string's energy, given a shorted coil. Could you please elucidate?
Thanks.
sumgai
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Post by UnklMickey on Jul 23, 2007 3:55:19 GMT -5
Sumgai,
We've been down this road before. Chris and I contend there is a "dynamic braking" effect. Like a generator with the output shorted. John says it's real, but insignificant.
I say leaving a coil hanging from hot is a small scale version of connecting a long wire to the hot. It acts like an antenna. You get more hum. Chris thinks I'm all wet on that one.
As far as I'm concerned, both should be avoided whenever possible.
Again, these are points we've already agreed to disagree on.
Cheers, Unk
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Post by sumgai on Jul 23, 2007 14:12:24 GMT -5
unk, I'm not looking for disagreement here, I'm looking for a deeper understanding. "Dynamic braking effect" is caused by back-EMF. But I'm under the impression that in order to drive a magnet hard enough to affect the real world, one has to use a pretty powerful current, as in amperage, not in voltage. Your generator example is good in that the coils are very low impedance, that being necessary to induce and carry the desired amperage levels, but that's also where the comparison breaks down. When shorted, our pickup coils still exhibit high impedance, thus making it difficult to believe that any significant amperage levels can be realized. I'm reminded of the sustainer project by 4real. He's found that he can't use anything like a pre-amp circuit, he's using an LM386 to drive the coil/magnet hard enough to excite the strings. That's an indicator to me that I'm on the right track here, in thinking that a shorted high-impedance coil can't produce enough current to cause the magnet to partially negate the string vibrations. I don't doubt for a minute that Chris hears a difference, I am only wondering at the explanation for it. Back-EMF doesn't seem to me to be the logical answer here, that's all. Measuring the effect of a shorted coil on the time a string can sustain a given level is not easy for the average hobbyist. Perhaps if we all collaborate on a methodology, some few of us can perform experiments that should be repeatable and verifiable, per the Scientific Method. And one thing you and I do agree upon is to avoid less-than-best wiring practices wherever possible. sumgai
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Post by ChrisK on Jul 24, 2007 17:55:42 GMT -5
Hmmm, Mmmmmmmmmmmmmmmmmmm................... Aaaaaaaaaaaaaaaaaaaaaaaaaaah.................. Errrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrg...................... Grunt, grunt, grunt, grunt, grunt, grunt, grunt, Nah, my ESP server is still down. Could you give me a clue and tell me which pickups that you actually are using (especially for the middle)? And, which coil that you want to be active in the single coil mode.
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