lvs

Even with maxed volume, there's still voltage division happening with the pickup's own resistance. For example with an 8K pickup and 1K volume, the pickup's output is attenuated by 16dB and the resonance peak is gone. The result is the same as plugging the guitar into a low impedance input. A 1K tone pot is like having one of "normal" resistance but turned down almost completely.

Okay, here's a diagram starting from the current configuration (or better, the one I saw on the photo - you might wanna check) and turning it into a parallel/single/single/series one. The result is electronically the same as a 4-position Tele. Only one of the diagrams on the right is the good one. You could gamble, and if you don't hear any change in tone while sliding the neck pickup switch back and forth, you'll have to swap white and black. Or you might wanna do the test that DarkAvenger suggested. There's also a slight chance you'll find out just looking at the bottom of the pickup.

It comes down to unsoldering a few wires and resoldering them elsewhere, no big deal but you have to determine first, at least for one of the pickups, which one of the two grounded wires comes from the coil because that one has to be unsoldered from ground and resoldered to one of the switches. If you want I can post a diagram to give you a better idea.

Your pics show each pickup has 3 wires. Normally, with a single coil pickup this means one wire connected to the beginning of the coil, one to the end of the coil, and one to metal pickup parts that should be connected to ground, like for instance a metal bottom plate and cover. Two black wires and one red for the bridge pickup. One black, one white and one red for the neck pickup. Both red wires run to the slide switches which get them connected to hot, all the other colors have a fixed soldered connection to ground. For a 2 pickups in parallel configuration this appears correct, and having two identical colors (red) running to hot makes a phase problem look less probable. Also, the wiring doesn't seem to have undergone any modifications even though it's not soldered in a very tidy way. These are of course assumptions, but reasonable ones in my opinion - a multimeter can provide certainty. I see in the meantime you got some more advice and you cleaned the pots - I'd say spray some WD40 into the slide switches also, there still might be a bad connection in there. A nice mod would be to rewire it so that with both slide switches in the off-position, you get both pickups in series instead of silence. No extra parts needed.

Fluent A/B comparison within the same guitar is possible with a switch between wiper and clockwise lugs of the tone pot, since shorting them together reverts it to a conventional volume & tone circuit. Could for instance be done quick and dirty running two wires to a switch dangling outside, if you don't mind a little temporary hum picked up by those wires.

... and another one derived from the previous, which allows both a TRS and TS plug. With the DPDT switch at position 1, the ring output is assigned to the neck pickup, the tip to the bridge pickup and the pickup selector is killed by shorting it. Normally a TRS plug is inserted. With a TS plug there will be sound, but only from the bridge pickup since the ring connection becomes grounded. With the DPDT switch at position 2, the pickup selector works normally and it's signal goes to the tip output, while the ring is connected to ground. Normally a TS plug is inserted but a stereo cable with TRS plugs will work of course too with a mono rig. But if the latter is running to a dual channel rig, the channel connected to the ring will be silent, but won't at least be humming, thanks to the ring connection grounded from inside the guitar. The point is, even at an accidental wrong position of the DPDT switch, there won't be embarrassing silence, and there won't be annoying hum. In my humble opinion, in the absence of cable sensing, a reasonable compromise. By the way, the Les Paul type selector can be also be a 3-way blade switch like for Tele. Lucas

... another one I dug up, maybe closer to what you want. With the DPDT switch at position 1, one guitar output is assigned to the neck pickup, the other output to the bridge pickup and the pickup selector is killed by shorting it. With the DPDT switch at position 2, the pickup selector works normally and it's output goes to both jacks. Lucas

I'm working on a two channel setup and after some complicated diagrams I came up with this simple one, meant for a guitar with two pickups. If only one of the guitar outputs (doesn't matter which one) is used, as with a normal guitar, the output swap switch works as a pickup selector. If both outputs are used (I'm gonna use a twin cable with 2 TS plugs at both ends), the output swap switch provides a choice which pickup signal goes to which output channel. At the other side of the twin cable, additional foot controlled switching is possible, though I don't think I'm gonna need it. The parallel On/Off switch overrides any setting of the swap switch : pickup signals are combined into one signal which is sent to both channels. And the pickup volume pots influence each other like in a contemporary Les Paul. Two separate output jacks in one guitar might be a bridge too far (when routing or drilling is not an option). It's possible to use one stereo jack instead, but it's troublesome using a mono cable with TS plugs then, because with the parallel switch to "On", the signal will be shorted to ground. Unless you want the parallel switch to double as a kill switch. Or you can also leave the parallel switch out if you're not interested in that pickup combination. Otherwise a stereo cable with TRS plug should be used, which can be seen as an extention of the internal guitar wiring, ending with two separate output TS jacks again. See diagram below. You might wanna try this idea - if eventually you don't like it won't have cost much work and money. Lucas

Plug a guitar cable into an amp with the other side unconnected and it will be very eager to pick up interference. Short the naked plug's tip and sleeve together and the interference is gone. First, the cable was "terminated" with an infinite resistance, and then with zero resistance. A passive guitar terminates the guitar cable with a resistance that varies as follows : With the volume pot at maximum this resistance approximately equals the resistance value of the pickup. Which is small enough to make interference unhearable. With the volume pot at minimum this resistance equals zero. With the volume pot between minimum and maximum, this resistance can become high enough to make the interference picked up by the guitar cable, hearable. Especially with a cable of less quality, and in a "hostile" environment, and with high gain settings. The maximum resistance, which equals the pot's own resistance divided by 4, happens approximately at the volume pot's resistive midpoint, somewhere between the minimum and maximum setting of the volume knob. For example, that would be 125K for a 500K pot, which is significantly larger than a pickup's resistance, around 10K. I think there lies a possible explanation for your problem, or at least an important part of it. The beginning of a cure consists in using cables of unsuspected quality, and keeping them away from interference sources.

Then I'd say by all means, go ahead and try the red one at that position and put two golds in series at the bridge. I share you concern about the red's output, but there's also more room available than with traditional pickups for adjusting the distances of the sensors to the strings so their volumes even out. The gold-gold can get pretty close before getting worried about string pull. Also, a dual gold at the bridge is a proven combination tonewise - I remember seeing one in a JB model by the way.

Hi Chris, I suppose you refer to the honky out-of-phase sound people sometimes get after installing a pickup whose polarity is unfriendly to the others. To my knowledge it goes like this : two single coils connected in series or in parallel, and having the same coil and magnet polarity with regard to each other, will sound in phase. The same goes when they have opposite coil polarity AND opposite magnetic polarity ("reverse wound, reverse polarity"). The other two combinations of coil and magnetic polarities result in a out-of-phase sound : that is, when there is only a difference in coil polarity, or only in magnetic polarity. So if you have two identical single coil pickups, and modify one of them swapping the coil connections and flipping the magnet(s), combining them will sound the same as before. That's often done with a Strat's middle pickup. But why combining a pickup with a RWRP one, since it won't matter for the resulting sound : to cancel out hum that's radiated from external sources (like for example an CRT monitor) into the coils, when both pickups are on. A simple explanation for the hum being cancelled while the string signals remain in phase, is that in the RWRP pickup, the string signal is "flipped twice" : once by the reversed coil, and once by the reversed magnet polarity, and like flipping a coin twice, the result is a null operation. The hum signal on the other hand is only affected by the reversed coil and not by the reversed magnet polarity, so it's "flipped once" and becomes opposite to the other pickup's hum signal, resulting in each other's cancellation. A single Lace Sensor is constructed in a way that the coil is "protected" against hum radiation by what Lace calls a "radiant field barrier". Is that it's only protection against interference or might there be more? Dunno. When combining two of them, I think it's enough to know that each one performs good against hum individually, so extra measures like making one RWRP would seem a bit overdone.

A red Lace Sensor is normally installed at the bridge, but of course there's no law against your own preferences. I think I'd be much interested to try red+gold as the "bridge dually" with the red one at the outside, and a SP on-off-on switch to select them separately or both in series. A SPDT could be used instead if both in series doesn't really sound like an asset. The extra pickguard hole for the switch could be avoided by replacing one of the tone controls with it. The remaining pickups and wiring would be like standard. So you end up with all stock tones possible from a SSS guitar, with the switch giving you an extra hot "superstrat" option. Just some ideas. As Chris said, Lace Sensors are electrically pretty close to standard pickups - they have coils too - but their magnetic structure is different. They pick up less noise and display less string pull. That said, one may suppose RWRP ones don't exist because they aren't necessary, however I must admit I'm not 100% sure. My own experience with Lace Sensors by the way was a gold-silver-blue set in a Strat in the past and they were quieter than traditional single coils for sure.

Just a thought : the pole piece you shaped is probably soft iron, while alnico, which is very hard and brittle, would be a quite different machining story. Anyway, keep those safety goggles within reach. Pedantic mode off now, and thanks for sharing your project. Cheers Lucas

I use SIMetrix. As far as I remember Rod Elliott once gave it a good rap at his website, and with the intention in the back of my head to learn to use a SPICE simulator some time, I downloaded it. I'm not positioned to say in what aspects it's "better" or "worse", because that would imply "compared to what" and I simply don't know how it compares to other simulators. It took me some time to get used to the GUI (and it's small bugs here and there) but it goes fast now. The free version is limited in the number of components, but most of the time it's enough for my small stuff. And then yeah, it's like a plane with a thousand knobs in the cockpit from which I had to sort out the ones useful for my purposes. But that wasn't too counter-intuitive, considering I seldom had a look in the manual. But better than my anecdotes, may I suggest you also have a look into this thread about starting a sim subforum at Diystompboxes : http://www.diystompboxes.com/smfforum/inde...p?topic=75038.0 . Aron has proposed to agree on a "default" sim application, and if (I hope that's a "when") the sim subforum comes alive, I know that's the one I'm gonna use from then on. (Sorry for topic digression.)

... however there is also feedback from the output of the transistor PP stage back to the input of the preceding opamp. During crossover a feedback voltage appears at the input of the opamp, which in turn makes the opamp send a signal through it's output that counteracts the distortion considerably. The quicker (better slew rate) the opamp can make it's output react, the better this works. I ran a little SPICE sim and the output has surprisingly low THD, with the output sine not deformed as far a I could see. When the feedback line is disconnected from the PP stage and reconnected to the opamp's output (giving a classic inverting opamp circuit running into a class B PP), you get the distorted curve like shown here in the quote. Hope this helps a bit to understand that stage better, surely not meant to embarrass anyone. About supplying the circuit symmetrically, one advantage I can think of is it can help against on/off switch pops.

From a quick & dirty SPICE sim I understood basically the following about the cap's working. Anyway, I feel this concurs with the experiences I had with it. - It causes a dip in the hi mid frequency range. As a result lows and highs sound of course more prominent. Since the dip can be fairly deep, it makes sense to tame that a little (or make it adjustable) with a (variable) resistor. Btw I accidentally found this mod when during a rewire I made a wrong tone pot connection. - Right before that dip, there's a small resonance peak. - Right after the dip, there's another, larger resonance peak with a frequency higher (1200ish Hz) than the resonant frequency of the whole pickup by itself, giving a little more single coil character. - The result appears to be sensitive to signal phases too. Think locations of the coils under the strings, also not excluding a combination of two SC pickups. Btw, Armstrong incorporated it into his 3-toggle Super Strat circuit using 10 nF caps that not only work as lowpass tone control - which in a Strat I find much more usable than traditionally larger values - but also work like the cap we're discussing here, when pickups are switched in series.

I'd say 10-12-15-18 nanoFarads are values worth trying. This cheap and simple mod was in a guitar of mine for a while, but now not anymore. I tested a large range of cap values on both pickups and it didn't work for me with the bridge HB but it sounded okay with the neck HB (and with the HB coil closest to the neck connected to earth, IOW the cap in parallel with that coil).

Nothing wrong with changing your mind. djhollowman, A good way to start I think is keep the Middle pickup out of the equation, wiring up your guitar the classic way with N and B pickups switched by the toggle and controlled by master vol and tone. Then to add the Middle pickup so that it mixes in smoothly in parallel with whatever Bridge/Neck selection, and following the master volume without overriding it, you can use this simple diagram. The Middle pickup's volume connected this way actually works like Fralin's Strat blender pot, which imo is a very good way to do it. He sells this pot separately. It probably will work ok with your pickups, but you might wanna contact him first to make sure. You don't strictly need Fralin's pot however : what you basically need for a usable result is an audio tapered one. Btw it's what Kinman uses in one of his "wirograms". There are a few considerations though. - The pot should be reverse log taper if you want to fade in the Middle pickup turning clockwise. If you think turning it backwards would be no problem, log taper can be used. The latter not counterintuitive if you see "basic guitar settings" as "all pots open". - When the Middle pickup is silenced an extra resistance will now always be in parallel with your other pickups, taking away some brightness. The larger the pot's resistance, the smaller this loss. With a no-load pot that resistance is ideally infinite. There are also ways to compensate like larger volume and/or tone pot, or a no-load tone pot, but first better try to avoid that. - The pot's resistance must be large enough so that it's able to shut off the Middle pickup completely. Linking the unconnected pot lug in the diagram to ground would make this irrelevant, but that doesn't fade as smooth. 250K might be too small, 500K is probably ok, 1M safe and a no-load pot ideal. - The pot's resistance must not be so large that the pot's hearable action happens within a too small part of it's rotation. I'd say possible candidates to join Fralin's pot are 500K-1M log or antilog, or 250K no-load.

Hi Traveler, If I understood exactly what you would like to have, With a 2 pole 3 position Strat/Tele Selector it's possible. They can be slightly different depending on manufacturer. The top diagram is a schematic with numbered connections, the bottom diagram is an example of how it translates to a switch layout, after identifying the switch's lug numbers.

For this application, your 3-pole switch must have only 2 positions to work properly here. How your switches should work exactly is depicted in grey. A suggestion : check what lugs are internally connected at each switch position with a multimeter to see they work the same as in those grey pictures. If you use a 3-pole on-off-on though, which I understand has one more lever position in the middle which adds up to 3, that middle position shouldn't be there and will not work properly, but if you whack the lever so that each time it skips the middle position, it will work. So you could install that for the time being and after evaluation drop in the right switch if you still think it's worthwhile. To answer your hot lead question : yep. (Edit : you can also solder that hot lead to the center lug of the 3PDT if that's more convenient.) And to fit the diagram into the whole guitar circuit, just treat everything between the leads marked "hot" and "cold" as a black box, as one pickup. But keep any ground lead that's connected to the base plate or any other external part of the pickup separated from those two, and from the 4 coil leads also. Run it to ground separately. You can't go wrong then. I'm off for a few days but I think you know enough, so I'm as good as redundant now anyway. Happy soldering.

Diagram (1) has a coil selector switch and a series/parallel switch. Diagram (2) is imo better : much more simple, has cheaper parts and switching is still intuitive. Unless you insist that it works as you described in your first post, I'd say use this one. Both diagrams can also be used for switching full pickups instead of pickup coils, but you can only have one master volume then. For switching pickups, diagram (3) shows still another possibility. Sw1 is just a regular 3-position selector like you'll find in Les Paul type guitars. Adding Sw2 creates the possibility to put both pickups in series. But it works as an override switch : switching to series works at any position of Sw1. These circuits can be combined with each other or with other stuff you may find elsewhere. Just one more thing : there are reasons to avoid a bunch of switches, like for example it's not the easiest thing to handle on stage. Another one is you might have seconds thoughts afterwards about having swiss cheesed your precious axe. But eventually what you want and like, counts imho. Anyway, I hope this helps.

Diagram with the essentials. For the splitted pickup combinations I took the ime better sounding ones. Positions 1 to 4 are humbucking. It might be a good idea to make 5 and 6 humbucking too, by mounting the neck humbucker with the screw pole pieces towards the bridge. (Normally it's bridge screw pole pieces => bridge and neck screw pole pieces => neck. And assuming both pickups are built equal polarity-wise.)

This wiring works like you want, with a Tele 4-way. Having two tone controls is not possible anymore so pot #3 becomes a dummy. Or it's reused, for example for something like Armstrong did with his superstrat circuit (drawn in grey, meaning it's optional). Grounding hasn't been detailed, to keep the diagram simple. Good luck, one advantage you already have is you heard the combinations and know what you want.

Wether the white zones should be black or not is actually not important, as long as it's understood they depict a zero resistance track portion over 50% rotation, while the black zones depict a logaritmically (or linear for diagram a) increasing resistance track over the other 50%. Based upon experiences with single Log tapered pots, I don't agree that b is impossible. Just hooking the resistive lugs of b to ground and the non-resistive lugs to hot, would actually give a much smoother pan transition around the center detent than c, and disconnecting the resistive lugs from ground so that it becomes hooked up ala Fralin would even be better. But I read at various places that all the action of this pot concentrates around the center detent - in a completely passive circuit, well understood.

Hi everybody, I wonder if you can help me with the following. A few days ago I adressed a question to several guitar electronics suppliers about the exact taper of the so-called blender pot, which consists of two stacked pots each to be connected to a pickup, so it's possible to have a panning control instead of a traditional 3-way selector. Only from Stewmac I got an answer but it didn't help me much further... I already knew that the pots are mirrored and they have zero resistance over 50% rotation. Here's an example. What I would like to know is which of the following diagrams depicts this pot's taper. The guy at Stewmac said it's Log but that still leaves a choice between diagram b and c. If you're not sure yourself, please don't post a guessing answer... thanks. If anyone has such a pot and a multimeter lying around, you're invited to do the following measurement and post it here : - Set multimeter to resistance measurement. - Connect one probe to a middle lug, other probe to a corresponding outer lug, doesn't matter if it's the CW or CCW. - Measure resistance at 0 - 1/4 - 1/2 - 3/4 - full rotation. Those data are sufficient for me to determine what taper these pots have. lvs