Simulating G&L PTB circuit

Pickups, wiring schemes, switch techniques and onboard active electronics for guitars
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ramonmaruko
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Post by ramonmaruko »

I am trying to simulate the G&L PTB circuit as shown in the schematic that was previously available in the G&L website.

I am having trouble getting the treble cut to work. The treble stays the same regardless of the value of VR2. Any hints as to why it isn't working would be nice. Thank you!

VR1 = Bass cut
VR2 = Treble cut
VR3 = Volume
screenshot of schematic
screenshot of schematic
Attachments
schematic.zip
LTSpice schematic and potentiometer library
(4.54 KiB) Downloaded 17 times

george giblet
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Post by george giblet »

You have drawn the circuit incorrectly.

Even if it was drawn correctly the simulation would not work. The treble control relies on the fact the pickup impedance is present. You have a voltage source. If you load a voltage source you do not change its output voltage. You need to add a pickup impedance model.

ramonmaruko
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Post by ramonmaruko »

Ah right, one of the pins of VR2 should be connected to the input and not to ground. Thank you!

As you've said it still won't simulate correctly. I'll see if I can find a model online.

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FiveseveN
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Post by FiveseveN »

Well you've tied both ends to ground. Look at the referenced schematic again (it's a normal guitar "tone control").
Edit: oops, I messed the replies above. For what it's worth, here's what I use for pickup simulation:
Attachments
cable.zip
Pickup, controls and cable loading LTSpice
(492 Bytes) Downloaded 17 times
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