How many sounds can you squeeze from your Brian May guitar?
Geeze, with all those switches you'd think that any pickup combination would be possible. Well, despite all those switches there are still a few combinations that are unobtainable on a stock Brian May guitar. Fortunately this is easily remedied. Presented here is an alternative way to wire the Brian May guitar.
This new wiring scheme will add a few new Strat-like sounds to your Brian May axe. By simply changing around a few wires you'll have access to eight new pickup combinations. As a bonus this modification is not permanent, you need only a soldering iron to do it, and you won't have to sacrifice any of the sounds that your guitar already has.
Do you ever get the urge to, you know, move over Rover, and let Jimi take over, but the Stratocaster sounds just aren't in in your Brian May guitar? Well, as Jimi Hendrix once said, "You know what I'm talkin' 'bout! Yeah, baby, get on with it!"
O.K., we'll get on with it, but first first a little background on the pickup configurations of the Stratocaster vs. the Brian May guitar. In the Stratocaster the pickups are wired in parallel (see Figure 1). Brian May, on the other hand, decided to wire his pickups in series (see Figure 2), which means that the output of one pickup is fed into the input of the next. Connecting pickups in parallel, like on a Stratocaster, allows the signal from each pickup to reach the amplifier by the shortest possible route. The result is that the high frequencies make it to the amplifier undisturbed, and this gives the Strat it's sparkling sound.
When the pickups are wired in series, on the other hand, some of the treble frequencies are suppressed. Why? It's because a long wire (pickup wire in this case) acts like a resistor -- the longer the wire, the larger the resistance value. There are two things to keep in mind: 1) a resistor in the signal path will suppress the audio signal, and 2) higher frequencies are attenuated more by a resistor than lower frequencies are. (This occurs because high frequencies have less energy than the low frequencies. Have you ever noticed that when your stereo is playing in the next room you can hear the bass, but you can't hear the treble? The treble frequencies don't have enough energy to pass through the walls, but the bass frequencies do. Perhaps you've also noticed that when you use a long guitar cable the sound isn't as detailed as when you use a shorter cable: longer cable = more resistance!). Anyway, the point is that when pickups are wired in series some of the high frequencies are lost because the signal has to travel through twice as much pickup wire to reach the amplifier.
The wiring method that Brian May came up with is really ingenious, because so many sounds are possible with his system. There are three Tri-Sonics single-coil pickups on the Brian May guitars by Guild or Burns. Each pickup has an on/off switch and an in-phase/out-of-phase switch, making for a total of six switches (see Figure 3). When two pickups are placed in series what results is a loud audio signal, assuming that the pickups are in-phase with each other. If you flip the phase switch of one of the pickups it causes the frequencies which are common to both pickups to cancel out. The sound doesn't cancel completely because each pickup amplifies different overtones due to it's physical position on the guitar.
This wiring scheme can result in some interesting frequency responses, and it is partly responsible for Brian May's signature tone. Take a listen to the guitar solo on "Bohemian Rhapsody." That crying guitar tone is created by putting the neck and the middle pickups in series and out-of-phase (and then driving the hell out of the amplifier).
These six switches provide twenty-one possible pickup configurations. Wow! That's a lot! However, eight of those combinations are actually redundant, which leaves only thirteen real-world sounds (which is still a lot).
Why the redundancy? This is best explained with an example. Take, for instance, two guitar pickups that are in series and in phase with each other. Now switch pickup #1 to the out-of-phase position. If you play a chord and listen, the sound will be changed dramatically because some of the frequencies have been canceled out. Now switch the phase on pickup #2. The sound is now the same as it was before you moved any switches, even though both of the phase switches have been changed. This is because the two pickups are in phase with each other, even though they are 180 degrees out-of-phase from where they started before you began messing with the switches.
It is because of this redundancy that you don't actually need all three phase switches to achieve the stock Brian May guitar sounds. You actually only need need two of them. Why not, then, use that extra switch to alternate between series and parallel pickup switching? You can't live with a measly thirteen sounds can you? NO! More is better!
The New Sounds
By making a few simple changes based around the "extra" phase switch for the bridge pickup (see Figure 4), you can add eight more pickup combinations to the thirteen that you already had. You will then truly have twenty-one different sounds. (You'll have to figure out the math on your own).
Two of these are hum-cancelling pickup combinations that you won't have without making this modification. If you play a high gain amplifier you'll know how important it is to have a guitar that doesn't hum. You'll want the reverse wound pickup to be in the bridge position instead of in the middle position (this is important to maximize the number of humbucking settings!!!). This way the best pickup combinations cancel the hum and noise:
That is five no-hum pickup combinations, which is more than any Strat or a Les Paul has!
Actually there is a SIXTH humbucking setting, which is a bit of a mystery to me (which is why I call it "the mystery setting"). When the modified switch for the bridge pickup is set to parallel, you can turn the other two pickups in phase and there won't be any hum. Basically, having the bridge pickup in parallel with the both the middle and neck pickups (which are in phase and in series with each other) seems to cancel the hum. I'm not sure why this works, since there all three pickups are turned on. If you figure it out please let me know.
Once you have completed this modification you'll notice that (if you leave the phase switch of the bridge pickup in the up position) you can still get all of the stock Brian May sounds by simply using the three on/off switches and the other two phase switches in the normal fashion. When you click the altered switch of the bridge pickup to the down position, however, that pickup will now be in parallel with the other two pickups. You can then manipulate the on/off and phase switches of the middle and neck pickups to get the new, non-stock sounds.
If you try to play with the bridge pickup by itself and the altered switch is set for parallel pickup combinations, you will get no sound. THIS IS NORMAL! Don't panic! You just need to click the new modified switch to the series position (or you could just turn on one of the other pickups).
Putting the pickups in parallel really brings out some nice jangly sounds that weren't there with the stock wiring. Plugged into a clean amp the parallel pickup combinations really shine, and they do have a Strat-like quality to them. My favorite combination has the bridge and middle pickups in parallel and in-phase. This provides a great rhythm sound.
Presented below are two new alternative wiring methods that can be used to achieve similar results, while at the same time keeping the function of the original switches intact. The switching systems below were developed in response to comments from Brian May about the above modification. These new switching systems both involve adding an extra switch to your guitar.
Apparently, Brian will sometimes change the phase switches to cause certain notes feed back differently. In other words, he will occasionally change the phase switches so that his guitar becomes 180 degrees out-of-phase in order to change the way the guitar reacts with the amplifier at higher volumes (even though the basic sound and pickup combination remains the same). Also, luthier Greg Fryer mentioned that it would be nice to keep the phase switches as they are in order to have the option of making sure that the guitar signal is electro-acoustically in phase with the amplifier/speaker. "Diagram 2" below shows a way to achieve the series/parallel pickup combinations as above without changing the current function of the switches.
Brian also thought it would be interesting to design a switching system that would allow a guitarist to change all three pickups from a series to a parallel configuration with a single flip of a switch. The "Super Cool, Yet Ridiculously Complicated, Modified Brian May Guitar Diagram" below shows how this can be done. The only catch is finding a switch that is tough enough to handle the abuse of a rock guitarist. An eight pole, double throw switch (8PDT) is necessary for this modification, but industrial strength versions of this type of switch may be difficult to find.
This diagram was sent to me by Maik Schrake of Germany. He was pondering the diagram above, and came up with a better solution for obtaining series/parallel combinations for the Brian May guitar. This is, in my opinion, the best way to wire the guitar. Thanks, Maik!
Here are a few more circuits that were sent to me by guitarist Steven Bragg. I've included his text (in italic) that accompanies the diagrams below:
I have seen diagrams of the RS circuit that look basically like the one I've drawn in BurnsStock. There are two different ways to wire the phase switches, and I've seen drawings of both ways, but for the stock scheme the two are electrically equivalent. I don't know if the volume and tone circuits are wired exactly as I've shown them but if not, they should be. That's the scheme that gives the least interaction of tone and volume settings, and makes a bypass capacitor basically unnecessary. The crucial point is that the tone pot should get its signal from lug 2 (the center lug) of the volume pot, not from lug 3.
Anyway, that stock circuit was designed by a 16-year-old (although an unusually intelligent 16-year-old) and though it is logical from a signal path perspective, it is actually more complicated than it needs to be. I have drawn a simpler, less expensive, and easier to wire circuit that is electrically identical, in diagram BurnsSPST. This circuit uses a simpler and less expensive SPST on-off switch, and allows for a less convoluted wiring path. As both pickup leads are floating, this does not load the circuit when the switch is closed. If you're not used to tracing signals in a schematic, note that closing the switch in parallel with the pickup bypasses the coil, turning the pickup off. The stock wiring does the same thing, but in a more roundabout way. The sound is identical. Having the on-off precede the phase also simplifies the remainder of the wiring. The advantage of this circuit is that it preserves the stock appearance and 6-switch setup.
A further simplification, shown in diagram BurnsDPDTcb, takes advantage of the availability of a 3-position DPDT-center-both (on-on-on) switch. This allows a single switch to be used for both on-off and polarity reversal functions. Center position is "off" (signal passes straight through the switch, bypassing the coil) and each throw is on, but of opposite polarity (phase). This eliminates the need for three of the switches, yet offers exactly the same pickup switching and phase combinations as the stock scheme. Note that the center lug must be wired to the output, not the pickup. Unlike the stock wiring, the two choices are not equivalent in this scheme. I have wired my own guitar, a strat copy, exactly this way, and it absolutely nails the tones of the RS, though it no longer sounds strat-like except when only one pickup is on. This circuit is ideal if you are building a guitar from scratch, or modifying another 3-pickup guitar as I did. I used minitoggle switches; I don't know if you can get a DPDT-center-both as a slider or not. I prefer the toggles anyway.
The previous examples offer simplified operation and easier assembly. The schematic shown in diagram Burns4PDT shows a more complex design, but one which is very versatile, perhaps allowing a guitarist playing a wide variety of styles to use a single guitar for all of them. In addition to all of the normal RS series sounds, it can also give all the normal Fender parallel sounds, but can also add parallel combinations not found on a stock strat, such as neck and bridge pickup on together, or all three, or true phase reversal of any or all pickups, etc. Unfortunately I can't find a way to do this without going back to the six switch setup for switching and phase. But you can use a simple SPDT for the on-off switches, which does simplify life a little. If you're modifying an existing RS, you can ignore 3 of the lugs on each DPDT on-off switch; you don't have to buy a new SPDT switch. You'll need a 4PDT switch to select the series (RS) or parallel (Fender, Gibson, etc) mode. An advantage of this scheme, compared to others that I've seen, is that the regular six switches work in exactly their usual way, no matter how you set the mode selector. There are no sounds or combinations you have to give up, and no oddball switch arrangements to remember. When I eventually acquire a RS, this is how I will wire it. I'll convert the volume and tone controls to concentric single-hole dual control, and put the series/parallel switch in the other hole.
A very important caveat: although I designed this 4PDT circuit, I have not built/tested it yet. It certainly looks like it should work, but I can't be 100% sure until somebody, perhaps one of you, wires it up and tries it. The DPDTcb circuit does indeed work in my guitar, but the 4PDT circuit should be considered experimental until proven.