The Catalyst Jakkerman


Some years ago Catalyst Instruments and Jan joined forces to design a new solid body guitar: the Jakkerman. Catalyst is a company that has developed a new compound material (SoundCompound®), which has fantastic sonic qualities.

Jan already possessed one Catalyst guitar, a Strat model, which he liked a lot, even though the Strat is not his favourite model. The design and specs of the standard Jakkerman can be viewed on the Catalyst site.

I will focus on the alterations made on Jan?s Jakkerman. The original model had a Seymour Duncan bridge pickup and a Kinman Strat pickup at the neck. Kinman is a top-notch single coil type pickup, with a patented design to make it as quiet as can be (more quiet even than most humbuckers!). However, it was a Strat pickup, whereas Jan wanted a Tele pickup, which was unavailable from Kinman at that particular time. So the neck pickup was replaced by an EMG-FTC, an active Tele replacement pickup. This of course had to be combined with the passive pickup at the bridge. More about this later.

Then there was the ?luxury problem? of the piezo bridge. Jan was acquainted and accustomed to piezo bridges on his electric guitars, and wanted one on the Jakkerman, too. A special one piece bridge was designed and produced by ABM. After some initial problems, the bridge now is one of the best piezo bridges for electric guitar (piezos made by Shadow). They surpass Fishman Powerbridges by miles!

However, combining piezo with magnetic pickups creates special problems. For instance, the differences in output impedance won?t allow them to be mixed without electronics. Therefore, most hybrid guitars (i.e. guitars with magnetic & piezo pickups) are ?stereo?, meaning separate outputs for both systems. This applies to the Jakkerman as well. Moreover, amplifying a passive piezo pickup is limited; one needs a special acoustic guitar amp. An active system can be routed to a mixing desk, or to multi purpose amps, as well as to acoustic guitar amps.

All electronic problems were solved by adding a Bartolini MPB1 dual preamp: separate preamp-buffers for magnetics and piezos. So the Seymour Duncan is routed to the magnetic input of the MPB1, and the piezo to the piezo input. All magnetic pots (2 volume, 1 tone) are replaced by 25K pots. Volume bridge comes from the magnetic output from the MPB1, volume neck directly from the EMG, then both go to the pickup switch, and back to the tone control.

The piezo volume control is replaced by a pan pot (2x25K), which regulates the balance between the magnetic & piezo volume). So the MPB1 piezo output goes to the pan pot, and then to the output jack (ring). The output from magnetic (at tone contol pot) goes to the pan pot, and then to the output jack (tip).

Thus, the piezo sound comes alive even more than the original sound, and is more universally applicable. And the active neck pickup and passive bridge pickup are combined without problems (mind you: the MPB1 does not alter the sound of the pickup; it just buffers it. Extra advantage: no sound loss when volume pot is used.) Of course, active systems need batteries, in this case one 9 volt battery. So I routed a cavity that fits a 9V battery holder. No screwdrivers are necessary to replace the battery!

So, a guitar that resembles a modern-day Les Paul, actually is an extremely versatile instrument. Ready to ROCK, but capable of much, much more.

Marcus van Engelen