Is there any way possible to have a humbucker read that it is an open coil and still function? The tech at Fender/ Charvel claim that EVH pickups reads nothing but still plays?
Thanks
No actually a pickup can have a broken turn somewhere and still get sound out. There is still current being generated in the coil so that one lead that is getting a voltage potential and I don't understand the physics of it, Joe Gwinn could explain it, but you will get some sound. I have personally experienced this in a dead tele bridge pickup, the sound isn't very loud but its there. Maybe at the extreme volumes that EVH uses it still works, but screw that they should fix the damn thing...
No actually a pickup can have a broken turn somewhere and still get sound out. There is still current being generated in the coil so that one lead that is getting a voltage potential and I don't understand the physics of it, Joe Gwinn could explain it, but you will get some sound. I have personally experienced this in a dead tele bridge pickup, the sound isn't very loud but it's there. Maybe at the extreme volumes that EVH uses it still works, but screw that they should fix the damn thing...
It's the self-capacitance of the coil that allows an open coil to work. Basically, the broken coil acts as if it were a good coil in series with a ~100 picofarad capacitor.
I recall a patent where something like this was done intentionally: The coil was bifilar wound (where a pair of insulated wires twisted together is used to wind the coil), and one wire of the pair goes to ground, the other to hot, and there is no DC connection between the two (infinite ohms). The bifilar winding will have capacitance between wires of the pair in the thousands of picofarads, versus a hundred pF or so. The claim is that this worked quite well.
Last edited by Joe Gwinn; 01-25-2007, 02:34 PM.
Reason: fix typos
I was going to say any pickup with a cap in series will show infinite ohms and work like a pickup. Villex bass pickups have a cap in them and you can't measure the DC resistance across the leads.
I was going to say any pickup with a cap in series will show infinite ohms and work like a pickup. Villex bass pickups have a cap in them and you can't measure the DC resistance across the leads.
Hey David, what do you know about those Villex pickups? You know he's the guy who invented the Lace Transsensor and Alumitone pickups. I figured the Villex pickups must use a similar idea. I haven't been able to find any info on them though.
Have you tried them out?
It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. — Albert Einstein
No actually a pickup can have a broken turn somewhere and still get sound out. There is still current being generated in the coil so that one lead that is getting a voltage potential and I don't understand the physics of it, Joe Gwinn could explain it, but you will get some sound. I have personally experienced this in a dead tele bridge pickup, the sound isn't very loud but its there. Maybe at the extreme volumes that EVH uses it still works, but screw that they should fix the damn thing...
I've also had that exact same thing happen, and also in a Tele pickup (a laquer potted one). Basically, it sounds like something that had a reedy out-of-phase tone.
I've had these Villex on the bench for 3-4 years without listening to them. For one thing he potted one of them backwards in the shell so his logo is upside down.
I just needed a J set the other day and pulled them out of the drawer. When I tried to hook them up to an Audere pre, they simply had no output, I measured them, infinite ohms. They also have 3 wires coming out and his schematic show 3 passive tone pots (mid, bass and treble). I assume he's got some sort of inboard L C circuit under the potting. These are clearly not designed for active bass applications.
I've had these Villex on the bench for 3-4 years without listening to them. For one thing he potted one of them backwards in the shell so his logo is upside down.
How can you tell on a Jazz pickup? I see on his website that the logo is on the left side of the pickup.
I just needed a J set the other day and pulled them out of the drawer. When I tried to hook them up to an Audere pre, they simply had no output, I measured them, infinite ohms. They also have 3 wires coming out and his schematic show 3 passive tone pots (mid, bass and treble). I assume he's got some sort of inboard L C circuit under the potting. These are clearly not designed for active bass applications.
Did you also wire the passive tone controls up before the pre? I bet you need his passive controls wired up. After all an active bass is just a passive bass with the first stage of amplification inside the bass, and not at the amp. I make pickups that are passive, but use a pre outside the pickup, so they are actually active.
I also thought he's doing some kind of LC network, but now I'm thinking it's some kind of transformer based circuit, because he also sells "passive boosters".
It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. — Albert Einstein
would love to read that pickup and WHY they did that? To darken the tone of a low wind coil is all I can think of, strange the weirdness one finds at the patent office...
I found it: US Patent Application 20020073829, to Gaglio.
That's pretty freaky. Anyone have any bifilar wire to try it out?
It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. — Albert Einstein
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