Installation Info

One property of the Blackpole™ pickups to which we paid particular attention is tuned and controlled microphonic characteristics: their construction maximizes desirable vibrational input from the guitar body while simultaneously rejecting microphonic squeal. Experience has shown that use of the supplied silicone rubber tubing optimizes vibrational transfer to the pickups.

These pickups are internally calibrated for the characteristics of each individual string, which is why you must specify wound or plain G applications when ordering. For this reason, the neck pickup should be installed with the exposed black poles towards the neck, and the bridge pickup should be installed with the exposed black poles towards the bridge.

In addition, the pickups’ magnetic and electrical polarities are configured so that the pair will cancel hum when both are run together in single coil mode. The wiring diagram here shows a scheme in which the maximum number of useful voicings (series/split/parallel) can be accessed.

The pickups can be used with either 250k or 500k volume/tone controls. However, we do recommend using the supplied .015mfd caps for the tone circuit.

The sense coil requires .550" of clearance between the bottom and top of the cover, so you’ll likely need about .600” of space between the high point of the arch and the low edge of the frets. Recommended thickness of top part of cover is <.030” at the ends (Ken Parker gets it down to .020”). It’s recommended that this cover top follows the level and contour of the top of the fingerboard end for aesthetic reasons, so the top flange of the coil is quite close to the strings - nearly even with the base of the ends of the last fret/top of the fingerboard at its edges. Bottom line: the sense coil is tuned for placement as close to the strings as practical.

These systems are designed with tuned microphonic characteristics, which is part of the way they represent the sound of a good archtop. If you (or your client) want less of this you can suspend the sense coil in foam between the sides & bottom of the coil and the case you make for it.

The cancellation coil (usually mounted under the pickguard) is .210” in depth.

A 470pf cap can be installed between the ungrounded legs of the volume control for smooth tonal transitions along the travel of the volume control. “Jazz People” sometimes like the slight dulling that occurs without this compensation element. A regular .022 can be used for the tone cap.

Here’s the Bronzebille system shown on 1/4” graph paper with the sense coil both encased and raw.