bostjan said:
I wish I saw this thread earlier.
I've made my own pickups a number of times. I never made anything that sounded better than what I could buy off the shelf, but alternating polarities to make a humbucker in a single coil (per string) fashion works just as well. There are some off-the-shelf hexaphonic mixers that can be used, or you can try passive mixing, but, IME, it does seem to lose some high frequencies taking that approach.
There are actually tons of different ideas out there. I tried doing a blade pickup with two coils side-by-side, wired in series, with alternating polarity, and that was probably my personal best result.
IIRC, Qtuners have their coils wound longitudinally, as opposed to transverse, like a normal pickup (rotated 90°).
Elysian TAPs do a cool thing where the "aperture" or diameter of the winding of the coils are different for each string. Think of it similar to how your iris contracts to let less light in when it's bright outside. Similarly, by varying the aperture of the inductor, you can focus the electromagnetic field into a tighter space. It's something I had never really considered as a variable when I first started playing with pickups.
Alumitones use a single "turn" of aluminium to keep the AC impedance extremely low, then use a transformer housed right in the pickup to match the impedance with the amplifier. It's a super clever idea, but it's something that is also super easy to implement yourself, to see what it sounds like. It really lowers the noise floor, without using any sort of active electronics.
The only kind of pickup I haven't successfully been able to get at all right is the sustainer pickup. I've tried so many approaches that I can't keep track of which methods worked the least poorly, but nothing I tried ever did anything like a real sustainer does, right off the shelf. But it's another nifty concept, and maybe you can play with that as well if you like. The basic idea is that one coil is a normal pickup, and then another coil has no magnet. You wire the normal coil to the input of an amplifier (I tried LM386 - a more high-fi amplifier chip should work better in theory), and then wire the output to the magnetless coil to drive the strings into a feedback loop. I'm not entirely certain, but I believe everything is low-passed so that the system doesn't just squeal endlessly, but instead drives either the fundamental or first or second overtone or a combination of those to keep the string vibrating as long as the player holds the fret down.
Great tips, thanks!
Elysian looks cool, and while I think it could be taken a lot further by my original plan of individual winds, that could also fail -- many pickups come tuned for the assumption of an unwound G, switch to a wound G and it's probably going to change volume a lot.
You're correct on the q tuner being wound 90deg opposite of normal.
My picture of sustainer pickups is a little different, however I only have experience with the Fernandes version. In that, it's a blade single coil and in sustain mode it's impulse / feedback amp is driven by another pickup (in the one I have, that's the bridge p/u). It's got the option of shifting between feedback of "natural" which I take to be fundamental, or "harmonics".
The only other sustainer I've looked at uses fundamentally the same design, at least based on the documentation of how you wire it.
The thing I don't love about the Fernandes, is it takes all the signal and pumps it back into all the strings, biased only by the string / magnetic circuit -- in natural mode that means the sustain decays to almost all feedback on a low string, memory says that's A, in harmonic, it's either G or B.
If I wanted to do it better, I'd again, use individually wound pole pieces per string, and have a fixed or adjustable biasing. That could probably be done with one preamp and some passive circuitry. Better still, use piezo saddles and amplify each one fed back to the corresponding pole. However now you're looking at 6 op amps, definitely too large a project!
Thanks again for the ideas!
