passive low end roll off advice?

[dan rathbun]

I've done it a couple of times and it works pretty good. You put a capacitor in series with the pickup. then you wire a pot that will bypass the capicitor when you want no roll off.

I still don't think i have found the best values for the pot and cap.

has any one found a great combo?

 

[Killed_by_Death]

G&L uses a 1 MegOhm C-taper pot & a 2.2 nanoFarad capacitor:

 

[ctmullins]

The best values for the pot and cap will vary according to which pickup, amp, cab, and ears you happen to be using.

 

[Gothic]

I put a .022 cap in series with the pickup, no extra pot to bypass. Works but doesn't roll off low enough, I'll probably get a bunch of lower value caps and try them on for size. Other than that, what the gentlemen above me said.

 

[bigtone23]

Since most bassists don't turn the passive bass cut control below about 5 (mine never goes below 8 on my El Toro), it works nicely to substitute a 250K linear pot for the 1M reverse audio taper. The pot value doesn't have any adverse effect on the circuit, and you get the same results of the original circuit's pot range from 10 to 5 spread out over nearly the whole rotation of the 250K pot. Here's a discussion on the pot change: BassesByLeo.com, est. 2009 • View topic - Bass Pot Replacememnt: 250K Linear vs 1Meg Reverse Audio
Here's a chart on the cap value and what it does. I personally use a 3.3nF (.00033uF) cap. I don't necessarily find a large, deep cut on the bass control good. The 6.8nF cap is rather subtle.

 

[Axstar]

4.7 nF is what Rickenbacker used on 4001 basses and what the current 'vintage' switch engages on 4003 basses.

 

[bigtone23]

I personally use a 3.3nF (.00033uF) cap. I don't necessarily find a large, deep cut on the bass control good.

Oops! .0033uF. Late night, tired brain post.
This is the same value as used on the "Strangle Switch" for the Bass VI.