Better? Maybe. Get More Sounds with this Easy Mod
Copyright 2003 Scott Humphrey
www.treblebooster.com
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:
-bridge and middle pickups in series and in phase
-bridge and middle pickups in parallel and in phase
-bridge and neck pickups in series and in phase
-bridge and neck pickups in parallel and in phase
-middle and neck pickups in series and out of phase
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.
Another great Strat-like pickup combo involves having the bridge and neck pickups in parallel and in-phase. What is really cool is that with this setting you have a humbucking pickup combination with which you can turn off the sound with the single on/off switch for the neck pickup. This can be used for an effect that I'm sure you've heard before (click here and I'll do this for you).
About the only pickup combination that you can't obtain with this switching system is the middle and neck pickups in parallel and in phase (the Stratocaster/Jimi Hendrix Little Wing setting). However, having the bridge and neck pickups in parallel and in phase produces an equally cool but different sound, and you can't get that pickup combination on a stock Stratocaster!
I hope you'll enjoy the new sounds that you'll achieve with this modification. Now, get on with it, baby! Yeah!!!
Trying to achieve some Brian May guitar tones? A treble booster is an essential tool for obtaining "that 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.
