RWRP: What does it mean?
Published on
April 4, 2025 at 1:08:16 PM PDT April 4, 2025 at 1:08:16 PM PDTth, April 4, 2025 at 1:08:16 PM PDT
In searching through single coil pickups, you may have run into something called "RWRP" or "RW/RP", and wondered what it means. I know what you are thinking, and no, it is not the initials of a Red Hot Chili Peppers tribute band. Have you ever put a new, highly recommended pickup into a guitar, only to have it sound worse than what was in there before? The issue may not be in the pickup itself, but in its relationship to your other pickups.
RWRP stands for Reverse-Wound Reverse-Polarity. This refers to the method used when making certain guitar pickups. Specifically, it's a combination of:
- Reverse winding: The wire on the pickup coil is wound in the opposite direction compared to another pickup.
- Reverse polarity: The magnetic polarity is flipped, so the north and south poles of the magnets are reversed.
Winding and Phase
The vast majority of pickup coils have fine wire wound in a particular direction around a central bobbin, either clockwise or counter-clockwise from the ground connection. If two pickups are wound in the same direction with the same magnet polarity, then they are said to be "in phase" with each other, and if wound in the opposite direction with the same magnet polarity they are said to be "out of phase".
But what does that actually mean?
Sound is transmitted in waves, and some of us may remember drawing curved lines in science class with crests at the top and troughs at the bottom. When two pickups have the same phase, the crests and troughs of their waves fit together and amplify each other for a stronger signal then either one alone. When two pickups have the opposite phase, one wave at a crest while the other is at a trough, those highs and lows will cancel each other out for a weaker and thinner signal - but a clearer signal at that with less extra noise.
Magnets and Polarity
Inside the central bobbin there will be Alnico rod magnets, metal polepieces, or blades that are either magnetized themselves, depending on the design, or that get their power from a larger magnet mounted underneath. Like all magnets, these have a North pole and a South pole, and the best pickup sounds come from having all North poles on one side (top or bottom) of each coil and all South poles on the other.
If two coils have the same polarity and the same wind direction, then their outputs will be additive to each other for a bigger sounding signal. With unmatched poles and the same wind direction, the signals can conflict with each other and cancel out lower frequencies by once again being 'out of phase'. This sound is not incredibly popular, but was famously pioneered (intentionally or otherwise) by Peter Green of Fleetwood Mac, whose Les Paul pickups were magnetically out of phase, and became an important part of the band's sound.So why RWRP?
So we have established that reverse winding and reverse polarity by themselves can lead to a weaker, thinner "out of phase" pickup signal, so why would anyone choose either of these features? Well, a brighter, clearer signal can be preferable in some styles of music like Funk and Ska, where the rhythmic stabs and chugs don't need as much darkness or 'body' to them.
But the truth is that the vast majority of players look for as much depth and richness to their guitar sound as possible, so how does RWRP get us any closer?
This is where the magic comes in:
- If you reverse the wind, but keep the polarity: out of phase.
- If you reverse the polarity, but keep the winding direction: out of phase.
- If you reverse BOTH of them: back in phase?!?
Wait a minute. Is that right? Why yes!
By reversing both aspects relative to another pickup, you end up with a thicker, warmer and more powerful sound. Plus, those conflicting waves that we mentioned earlier completely kill any annoying 60Hz hum in the circuit, which is why that effect is called "humbucking". Those of us that have struggled with 60Hz hum are very grateful for that fact.
So what does this mean for my guitar?
If your guitar has only two single-coil pickups, like a Telecaster or Jaguar, RWRP will mean that the middle position where both pickups are activated is hum-cancelling. If your guitar has three single-coil pickups, like a Stratocaster, having the middle pickup be RWRP compared to the bridge and neck pickups means that positions 2 and 4 on the five-way switch will be hum-cancelling. And you can continue on in this way as you add pickups - as long as each pairing is RWRP to each other, then each pairing will "buck the hum".
If you pair a pickup from one company with one from another company, their standard wind directions and/or polarities may be different, so you will certainly want to keep that in mind. Changing the wind direction or polarity after a pickup has been built can affect your sound and possibly damage the pickup, so both are usually better left to the professionals. If you ever have questions about this, reach out to the respective pickup manufacturer(s) - we love to talk about our products and most of us don't bite!
Please remember, as in the Peter Green example, that humbuckers are double-coils with their own internal RWRP setup, but even a pair of them can be out of phase together if their closest coils or magnets are not matched up correctly.
Hopefully this has cleared up any confusion about reverse-wound reverse-polarity pickups, how they work, and why you do or do not want them. In the search for your guitar's perfect voice, no stone will be left unturned and no option will go unexplored, so go find your sound and love your tone.