Implementing passive EQ scheme(including inductor) need help

[RoadToNever]

This is a draft for a passive EQ scheme I put together. It's a bit of a hack yet it's the only way I've managed to implement the controls as functional. The main issue I've run when I try to remove the hack-ish second connetion to the jack is tone control behaviour becoming similar to a volume control killing signal at "0".

[David Schwab]

This was posted over at TalkBass. You are shorting out the volume pot lugs, and from what you said over there the tone cap value is wrong, and it sounds like your tone cap is bad.

Are you expecting a different answer over here?

Just do what people are telling you to do at TalkBass and replace that tone cap.

[RoadToNever]

I figured there would be a chance I'd get get a reply from someone technically minded. My LCR meter tell me my cap is fine BTW. Forget about it, I'm looking up the L6s and L9s diagrams to see how the controls were implemented there. Bye for now...

[David Schwab]

Well you were getting answers from technically minded people (including me) at Talkbass. We are trying to help.

The Gibsons use a very different setup from the Q filter. Also, I think the Q filter has a cap in it. He makes a Q filter and an L filter. The L filter was just a coil.

You can wire the Q filter up to a tone pot and it will be just like the L6-S.

I had a Q filter in my Fender Mustang guitar back in the 80s and didn't really care for it. All it did was sort of smooth out the high end without rolling off the treble.

Your issue was the tone control working like a volume control however, which makes no sense if it's wired up the right way.

Does the tone control do that when the Q-Filter is out of the circuit?

[RoadToNever]

Well you were getting answers from technically minded people (including me) at Talkbass. We are trying to help.

The Gibsons use a very different setup from the Q filter. Also, I think the Q filter has a cap in it. He makes a Q filter and an L filter. The L filter was just a coil.

You can wire the Q filter up to a tone pot and it will be just like the L6-S.

I had a Q filter in my Fender Mustang guitar back in the 80s and didn't really care for it. All it did was sort of smooth out the high end without rolling off the treble.

Your issue was the tone control working like a volume control however, which makes no sense if it's wired up the right way.

Does the tone control do that when the Q-Filter is out of the circuit?

The current Q-Filter is just an inductor(hum-cancelling)with a with external cap and resistor included in the package. I wouldn't have drawn it like a plain coil otherwise. The tone works as expected with the Q-filter out of the circuit and I don't care what you though about the Q-Filter 25 years ago...

[David Schwab]

The tone works as expected with the Q-filter out of the circuit

Well then I guess you have to revamp your circuit. The Q-Filter is supposed to replace the tone control. There must be an impedance interaction going on when using both at the same time.

Maybe if you put the tone control on the input of the volume pot, and the Q-Filter on the output.

Or try wiring it up like an L6-S (also designed by Bill).