Let me first say this:
The Seymour Duncan Custom Shop RTM bridge humbucker is one of the coolest pickups you’ve probably never thought about trying.

When the good people at Seymour Duncan told me I could choose any Custom Shop model to review for this blog, I had no idea which one to pick. Generally, all of my guitars sound pretty good. There were no glaring weaknesses or trouble spots that really needed addressing, but I had my pick of some of the best custom-wound pickups in the business and I was absolutely not going to waste that opportunity.

I got to thinking about where I could squeeze a little something extra from one of my guitars. I already had some custom-wound pickups from various manufactures in a few guitars, so my focus turned to replacing one of the OEM pickups still present in one of them. I ultimately settled on my recently-acquired USA G&L Legacy HB, a guitar that comes stock with a  Seymour Duncan TB-4 JB bridge pickup.

I like the JB. I’ve used it in a lot of different guitars, but this guitar is a little on the brighter side of the tone spectrum, so my question became, “What Seymour Duncan Custom Shop pickup is similar to the JB in output, but will give me a tighter low-end, more mid-range bite, and sweeter highs than the JB?”

Unfortunately, while the Seymour Duncan website contains great descriptions, tone samples, and even a Tone Wizard for determining the right regular-production pickup for your application, it offers very little info about any of the offerings from the Custom Shop. I knew the general specs of the JB and used them as a place to start, but still came away with a list of about four different custom shop models to choose between and no idea which of them to pick.

In a move I cannot recommend highly enough, I took my question to the large, knowledgeable, and extremely helpful user-base of the Seymour Duncan User Group Forums, who had me sorted out and oriented on the Warren DeMartini RTM humbucker in short order:

[…] if you have the GAS for a CS pup, the RTM is a good way to go for what [you say you want]. just think of it as a JB-Plus.

– darthphineas

It’s wound like a JB, just a little hotter, and with an A2 mag. It’s fatter sounding than a stock JB. With each bobbin being wound similar to a JB, you’ll get a nice overwound single-coil sound when split, 8.8k DC resistance.

– ErikH

Forum member darthphineas was even cool enough to message me and offer more insight into the sound and feel of the RTM, and answer any specific questions I might have about it. How cool is that?

I was sold! One RTM, please! Trembucker-spaced (to align properly under the strings of my Legacy), with four-conductor wiring (to let me wire it for a coil-split and give me single-coil sounds too), and no silk-screened logo on the bobbins (to better match the all-black look of the guitar, and because the Custom Shop will do that for you).

It took about four days to get my pickup. What follows is a brief pictorial of what you experience when you order a Custom Shop pickup from Seymour Duncan.

It arrived double-boxed and securely-packed. The first thing you see is the big sticker with your specs listed on it.

The “MJ” you see here stands for Marciela Juarez. She is the mysterious pickup-crafting master who winds pickups for people like Jeff Beck, Slash, Yngwie Malmsteen, and myself.

They really don’t want this thing shifting around when they ship it to you. A little different than the clear plastic toy box some other pickups are shipped in, eh?

The box contains about what you would expect: A retainer ring, screws, springs, leaflet, and the pickup itself.

The leaflet unfolds to reveal a number of nice full-color wiring diagrams.

The pickup shows a nice attention to detail in its construction. All the materials are of the highest quality and it’s very cleanly assembled.

The baseplate contained a notable surprise! I was not expecting it to be autographed by Warren DeMartini. I’ve got to admit it, that’s pretty cool.

Here are a few clips recorded with the RTM.

The first clip in the set is a direct riff-for-riff comparison of a clip I recorded for another article, using the same guitar with the old JB pickup installed. What you hear first is the original riff using the JB, and the same riff played with the RTM immediately after. If your ears are like mine, you’ll hear how much tighter and more muscular the RTM sounds, while still retaining a very similar vibe to the JB.

The rest of the clips feature the RTM in varied applications. I haven’t found anything it can’t do well.

After living with the RTM for a few days and trying it in several different applications, I would say that it’s exactly what I was looking for. It’s a little tighter and more aggressive than the JB it replaced. There is an exciting top-end sizzle to it that never approaches ice-pick treble, but makes high notes really jump out of the guitar.

The coil-split tones are also very convincing and blend as well or better with the G&L single-coils than the JB did to my ears.

Overall, I would join the folks on the Seymour Duncan User Group Forum in recommending the RTM to anyone who likes the JB but is looking for a slightly more powerful sound with a more refined EQ curve. I have not been disappointed.

(Master pickup craftswoman MJ with Mr. DeMartini.)
Interesting fact: RTM stands for “Rattus Tonus Maximus.”  I wonder which of these two came up with that?

If you are considering a custom shop pickup from Seymour Duncan, don’t be put off by the lack of flowery descriptions on the website. Do what I did: join the forum, ask around, and you will be met with more than enough useful information to make an informed choice.