Pickups

2008 Power Jet Wiring Revelation?

1

I have tinkered with my powerjet over the past 9 years.

Mods include: cutting out the mud switch Splitting the powertrons with pull pots on the two volume controls treble bleed on master volume

SO the point of the post is I was playing the other day on a fender champ 12 which is a channel switching small amp. Has a clean channel and a GAIN channel.

Regardless of what pickup combination I was using when I was in the GAIN channel and would turn down the master volume the GAIN would remain but volume output would just get quieter BUT when I would be on a single pup and have the master volume all the way up but would turn down the individual pup volume it would clean up?!? Gain goes away and it gets glassy.

Any idea why this would happen on one volume pot and not the other? Something I just dont understand I am sure but thought it was fascinating.

2

Tell me what you think Gain means.

3

Tell me what you think Gain means.

– Billy Zoom

Great question! I am probably wrong but I think about it sonically. I would use the adjectives distortion or even crunch. That make sense as a description even if I am wrong?

4

Gain isn't a sound. It's an increase or "gain" in signal strength. On older amps, it was called a Volume knob, but when they started adding Master Volume knobs, they started calling the original volume control a Gain knob, because while it increased signal strength, the actual volume or loudness was now limited by the Master Volume control. Boosting gain in itself does not cause distortion or any change in the tone. The idea of a gain knob on a guitar amp is that if the signal is boosted enough, the preamp will eventually overdrive and distort. The preamps in modern guitar amps are designed with little headroom so that this occures easily. So...the Gain knob on the amp turns down the signal in the preamp, just as the volume knob on the guitar turns down the signal to the preamp. Turning either of them down should prevent the preamp from distorting. Therefore, I don't understand the question as you stated it. If you're saying that turning down the Master Volume on the amp lowers the volume without changing the preamp distortion, then yes...that's what a Master Volume on an Amp is for...so you can get distortion at a low volume. Turning down either the Gain knob, or a Volume knob on the guitar should clean up the distortion without lowering the overall volume.

5

Hey billy thanks for the clarification. The master volume knob I was talking about is on my power jet. Not the amp. So the difference I was hearing is based on turning down the master volume on my guitar vs turning down the individual pickup volume on the guitar

6

That's odd. The volume controls on the guitar should all do the same thing except the Master works on both pickups. The Master is the only one that actually lowers the impedance of the guitar, but I don't see why that would matter to a Champ 12 circuit.

7

Yeah that is what was so odd! But it is totally different.

Using master volume and the distortion stays with the sound turned up or turned down low.

Using individual pup volume pot and the distortion goes away and the guitar tone cleans up glassy

8

My un-scientific guess: It might have something to do with the treble bleed on the guitar MV. You are turning down the MV, but part of the signal is still passing and may be what you hear as distortion.


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