Capacitor on a Mid Control in an Active Preamp

[KennysFord]

Hi Folks,
I recently upgraded the Preamp in my Lakland 44-01 from the Bartolini MK1 (which isn't really a Bartolini) to the Bartolini NTMB jobbie. All in it's an improvement however the Mid frequency is set at 250 hz. That in itself is causing me a bit of a problem in that 250hz is a frequency range that I have a particular dislike for.

However, not all is lost, according to the Bartolini wiring diagrams I can put a 0.33uf Cap in series on one of the wires going to the Mid pot and get a much more pleasing to my ear 500hz boost and cut.

Link to PDF on the Bart site
http://www.bartolini.net/wp-content/uploads/2014/07/NTMB+-Mid-Switch-Configuration-min.pdf

Now I think I'm right in saying ( please tell me if i'm wrong) that "In Series" will mean simply cutting the wire and soldering the cap into the wire but I'm unsure if it would have to be a particular way round, ie, + - . Also, I know the Cap in a passive system gets soldered to the tone pot outer casing, is there a need to do this on this active circuit ?
If any of you knowledgeable folks could assist me I'd be eternally grateful.
Thanks in advance.

Edited February 2, 2015 by kennyrodgers

[Woodinblack]

There is no way round, just one 330nF capacitor and no, don't solder it to the tone pot casing, as that would classify as bad

[Guest]

We don't want Bad
Many thanks for that, I have a couple here I can try out, a .22 and a .47, either or should get me close enough for the time being.
Thanks again.

[Guest]

Sorted.....for now.
Just popped a .22uf in there and much more pleasing to my ear now.
I can see a bit of experimentation looming...... I could possibly get a stacked Bass / Treble then I could add a switch for selectable mids.
Ooh what fun.