Ibanez JD9 Jet Driver clone help

[nognow]

Hey!
I recently built a replica of the Ibanez JD9 Jet Driver(which is basically a TS9 with a little more gain and a mid control) as seen here:
http://tagboardeffects.blogspot.co.il/2014/07/ibanez-jd9-jet-driver.html

It works fine but I have some small problems:
1.first,the mid frequency controlled by the mid knob is WAY too low for me ,it is unusable past 10-11 o'clock. Can I change the 47nf cap across the 2 leg of the mid pot to a lower value? (http://s27.postimg.org/ki94w634j/Ibanez_JD9_Jet_Driver.png)

2.I have a set of OPA2134 in it, can I run the pedal at 18v from a regulated,stable power supply?(all the caps are rated at 25v or more,1/4w resistors)

Thanks!

[nognow]

anyone?

[duck_arse]

as for 1), have a look here, you might find an answer:
http://www.muzique.com/lab/tstone.htm
ahh, mid control. do you have a circuit diagram?

and as for 2), the datasheet says they're good for +/-2V5 to +/-18V, so yes.