Getting to know your pickup: a tool for measuring the frequency response of the impedance

Here is something very useful and special:

GITEC member Helmut Keller (an expert in instrumentation for studio acoustics/electronics, and for RF,  and an avid guitar player) has put together an exciting tool for measuring our pickups:


Contrary to all those more or less useless (but unfortunately ubiquitous) DC-resistance measurements that cannot really tell much about the image a pickup will paint sonically, what we have here is a scientifically sound, highly relevant measurement of how the AC-impedance evolves over the auditory frequency range. The result is probably THE most important clue of how a pickup sounds.

What’s more, Helmut’s tool requires merely an ordinary computer with a reasonably good sound card (or audio interface) to run a few programs, and a VERY simple hardware measurement adapter that can be built (that term is almost an exaggeration!) by basically anyone – because it consists of nothing more than a few jacks/plugs, a bit of cable, and a single resistor, plus a switch.

Best of all, Helmut has given his software (as well as the accompanying article/manual/explanation he has written up: Pickup Wizard 0.4) to GITEC to post them here – completely free of charge!! You can download everything as a zip file (Pickup_Wizard_Version_0.4), unzip it and sink your teeth (figuratively, please!) into getting some really significant measurements done!

By the way: those impatient ones that do not want to dwell much on science but like to dive into applying it right away, they may skip “the theory” in Chapters 2 – 5 of the article/manual/explanation and fast forward to Chapter 6: putting the measurement adapter together.

Helmut has tested the software at length with his WINDOWS machines, and at GITEC we have started to test it with LINUX operating systems, and on the Mac, as well. With LINUX, we are making much progress: it seems that there are no problems. We are still testing on Macs but are confident that success can be established on these machines too.

In any case, Helmut is happy to receive our feedback, and already plans to issue an updated “professionalized” version of the 🧙🏽‍♂️ soon. I liked Helmut’s contribution too much, though, to keep it from you and simply HAD to post it already now/here!

‘Nuff said!!

Here is all the material: Pickup_Wizard_Version_0.4

and here’s just the article/manual/explanation as a PDF-document for those who want to simply inform themselves first: Pickup Wizard 0.4

Measure away, then, and have fun while really exploring your pickups!


Enhanced possibilities: Active Guitar-Electronics

In our third installment of articles by Helmuth Lemme, we go  – compared to the last topic of low impedance pickups and a lot of tricks to get various sound out of passive guitar electrics – completely the other way: we are looking at the possibilities that active guitar electronics offer. Once we get over the issue of having a battery onboard our guitars, active electronics would really seem the way to go. No more worrying about cable capacitance and length, about passive controls robbing high end and “cut” in our sound. Active filters are possible that get rid of muddiness in the sound, or push the mids for a really screaming solo …

So let’s see what Helmuth has to say about

Active Guitar Electronics ….

P.S.: this article was originally issued in the magazine SUSTAIN (May, 2013); we appreciate being given the permission to re-publish it here!

A vintage story: restoring an old Burns Bass

Helmuth Lemme is not just an expert in electronics but also a true hands-on craftsman who loves working on guitars and basses. He has a particular knack for bringing derelict instruments of lesser well-known makes back to life, actually not just restoring them but often making them much better in sound and playability than they originally were! One example case is described in the article

Restoring an old Burns Bass

a read of which should be a lot of fun for every vintage aficionado!

P.S.: this article was originally issued in the magazine SUSTAIN (May, 2013); we appreciate being given the permission to re-publish it here!

Potential trouble-makers in the amp: Passive Offenders

In the last articles posted here, author and guitar & amp expert Helmuth Lemme has been looking at pickups and circuitry in guitars … now we switch to the partners of these instruments, the amplifier. There is a lot of continued discussion about tubes vs. solid-state devices, and indeed these active components are what drives the amp. However, passive components are required, as well – and although they are much less discussed, they are worth some consideration, too … especially in tube amps. On this subject, check Helmuth’s article

Passive Offenders

P.S.: this article was originally issued in (August, 2015); we appreciate being given the permission to re-publish it here!


Under the looking-glass: Measuring Pickups

Magnetic pickups for electric guitars really are very simple devices: a magnet, some wire wound as a coil within the magnetic field … that’s it. However, due to the specific circumstances around the electric guitar and ist amplification as it has historically evolved, these pickups have some idiosyncrasies that give them their sound. Of course, our ears are the real judges when it comes to that sound … but our ears have their limitations. Moreover … or rather to add to the issue,  a brain (hopefully 😉) is connected to these ears which brings perceptional psychology into play and many corresponding potentially ‘erroneous zones’. Physics certainly can be of help to avoid some traps when judging the sound of pickups – specifically, make some measurements here and there can be most helpful. Beware, though: the very popular simple measurement of the ohmic resistance of pickup DOES NOT CUT IT! There’s more to consider, and this is what Helmut Lemme’s article on there matter is all about:

Measuring Guitar-Pickups

P.S.: this article was originally issued in the magazine SUSTAIN (May, 2013); we appreciate being given the permission to re-publish it here!