Seymour Duncan uses the terms “Passive Mount” and “Active Mount” but not universally across all models, needlessly confusing matters but it’s Seymour’s company, he do what he want. These terms are applied to certain seven and eight string models, refer to the shape of the route the pickups are intended for, and have nothing to do with whether the pickup itself is active or passive.
“Active Mount” Seymour pickups are in a rectangular soap-bar shape and need a larger route than most standard pickups. They take wood screws and are therefore direct mount. Why soap-bar? Because there was a time when guitar builders looking to install active seven string pickups as standard equipment only had one choice, a soap-bar shaped EMG. So there are a number of ugly guitars floating around with huge holes in them ready to get stuffed with after market replacements.
“Passive Mount” Seymour pickups are like any other Seymours that use machine screws (unless they are the active “Passive Mount” models**) for ring or guard mount but are labeled as such simply because they have an “Active Mount” variant.
So Passive “passive mount” are ring mount with machine screws, active “passive mount” are direct mount with wood screws, “active mount” are direct mount no matter passive or active and everything else may or may not be direct or ring mounted***.
6 string humbuckers are ring mount, 7 strings are direct mount, 8 are whatever? You just have to look at the pictures. It’s a pain in the ass but at least they don’t intentionally spread confusing bullshit Although they, along with Ibanez, caused a lot of this initial confusion (leaving EVH out of this for now****) by producing OEM models for Ibanez to direct mount before most other large manufacturers were doing such things. So much like our gaping EMG hole problem discussed earlier, we have a bunch of guitars floating around that look pretty without rings that need aftermarket direct mount options.
They don’t do direct mount. Guess your screwed, maybe.
6 strings are all direct mount, 7 and 8 strings have options for direct or ring but with direct you’re gonna get an ugly soap-bar. Sorry.
So what can be done when the pickup you want doesn’t have a direct mount variant for your direct mount guitar?
Provided it fits (it may not) easiest thing to do is modify the screws. I first sharpen the provided machine screws to a point, then chuck them into my drill press and file a smooth shank just below the head. Since machine screw thread is finer than a wood screws I’ll often plug existing holes without pre-drilling new ones so the thread has something to grip, the sharp point aides in threading the screw into the wood. The flat shank is so the screw can thread all the way through the pickup base hole and “bottom out” at the head, allowing the screw to turn freely without stripping anything.
If the pickup doesn’t fit, rather than grind the mounting plates or routing the guitar I’ll try to retrofit the new bobbins on the existing plate. Sometimes it works, sometimes it don’t.
Last resort is some routing, maybe a pickup ring, maybe some other custom solution like cutting or grinding your nice new pickup, which we can discuss. Call me so we can talk.
Or call me so you can listen to me breathe.