Doing Things Wrong

Artec EXP Active Tone Control

My verdict on active tone controls for a guitar is that they are not worth it. There is already plenty of treble, and not enough bass that boosting it will make much difference. If you want to try an active control on a guitar, try an onboard distortion instead.

But the Artec EXP tone control is a funny thing. In the middle, it gives a flat clean boost. Turn it forward, and you get a high/low boost, or what amounts to a mid-scoop. Turn it back, and it gives a mid-boost. Sounds interesting, so I decided to try one.

I mounted it in the Kubicki guitar, which uses a pair of humbuckers, and needed something to justify the third knob. And the EXP mostly does what it promises. There is a noticeable overall gain, with little or no additional noise. The mid-boost setting is as advertised - the opposite of anything I would want. The other end gives a strong boost to the high frequencies, shimmery, almost shrill. But as I said before, there is not enough low end on a guitar that boosting it makes much difference. Even an open E does nothing. To my ear, the frequency range of a guitar just does not respond well to active tone controls, unlike a bass.

So this is a negative review? No, not really. The EXP certainly does something, you might like it. You might have a better ear than me. I'm just a dumb old bass player. The EXP is fairly inexpensive and easy to install. It makes an ideal replacement for that useless second tone control on a Strat and many other guitars. Try one. It might be really interesting on a bass.

One thing to note: if you are wiring in an EXP together with a standard tone control, place the other tone control upstream from the EXP. That is to say, on the input side of the EXP. If the other tone control is downstream of the EXP, it will be rendered ineffective, except as a volume cutoff. You can place the volume control anywhere, I like to put it just before the output jack, so that any other controls have the maximum amount of signal to work on.

This unadvertised "feature" of the EXP gave me some fits, and I spent a while swapping out different tone controls until I realized the problem went away when you disabled the EXP. I put the original tone control back in, but moved it from the volume control to the pickup switch, and now everything works fine. Must have something to do with the output impedance of the EXP; I didn't strain myself over it. I'm no Joe Walsh in the brains department.


When two pickups are wired in series, the output of one is connected to the ground of the other. The outputs are directly additive, there is no loading effect as with parallel wiring. You get noticeably more output, and usually a much fuller sound. Two pickups may be wired in series with a standard [ON-OFF-ON] switch, available at any hardware store.

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