Any experience with Q-Filter by Bill Lawrence?

[eutgard]

Does anybody have experience using Q-Filter by Bill Lawrence?



It is an LCR Network to reduce the impedance of pickups.

http://www.billlawrence.com/Pages/Pi...w/Q-Filter.htm

And at http://p082.ezboard.com/fguitarsbyfe...tart=1&stop=20 I can read many posts about it, but there is no bass Q-Filter review.

[GlennW]

No experience, but it's main use is to thin the sound with high output guitar pickups. If you have a regular pickup you'd probably be better off looking at capacitors.

[DavidRavenMoon]

I used to have one of these back in the 80's. It's sort of like a Varitone control, but at one frequency. It notches out the upper mids and mellows the tone.

I didn't have any problem using it with standard output pickups. I had it in my Fender Mustang with Lawrence L-250's. I didn't find it very interesting and removed it.

[BassJunkie730]

The way i understand it (I have a q-filter too that's been bascially sitting in a box for years)

the Q filter reduces the inductance of a pickup - and it's effects are specific to the pickup - NOT a specific frequency point.

If you happen to have to high inductance pickups with the same frequency response - then it will appear that the filter notches out something - but that's not what it's designed to do and anything that relates to a frequency being attenuated or accentuated is indirectly a result of applying the filter to a pickup.

[DavidRavenMoon]

Originally Posted by BassJunkie730

The way i understand it (I have a q-filter too that's been bascially sitting in a box for years)

the Q filter reduces the inductance of a pickup - and it's effects are specific to the pickup - NOT a specific frequency point.

If you happen to have to high inductance pickups with the same frequency response - then it will appear that the filter notches out something - but that's not what it's designed to do and anything that relates to a frequency being attenuated or accentuated is indirectly a result of applying the filter to a pickup.

Now he says it lowers the impedance. But when they came out he said it made a sweeter top end. It was supposed to replace your tone control, to mellow the tone without making it muddy. So clearly is was creating a notch in the mids.

I'm not sure how an inductor will lower either the impedance or inductance of a pickup.

If you short an inductor to ground, it will roll off the low end. If you make an LC network, it will create a notch at some frequency.

He used to sell two different filters.. one made a humbucker sound like a single coil, that was the L-filter I believe. That was clearly just an inductor, and in fact you could add a cap to make it a varitone.

As with any passive tone tone control, the hotter the pickup, the more effect it has.