mid boost

[dscottguitars]

Hi,  I have a question about the resistor used in this mid boost circuit and if there is any reason it can be eliminated in mine.  I took the circuit from a Fender Concert I had, see the schematic.  It uses a 10 meg resistor across the switch, but I can't see any reason for it being there.  I also have my preamp schematic with and without the resistor and would like to know if it can be used without it.  It seems to me I am just switching in another capacitor in parallel with the one on the treble pot.  It would make the total capacitance 2270pF vs 2000pF.

Thanks,

Daniel

[zendragon63]

You often see large resistor across switches to minimize the 'pop' that can occur when engaging or disengaging the switch. Discharges the adjacent capacitor. If you don't need it--you don't need it. You can get away with lower value--4.7M if you need though. Regards

dennis

[dscottguitars]

Didn't think of that, thanks...

[HotBluePlates]

... It would make the total capacitance 2270pF vs 2000pF.

It makes the total capacitance 2270pF vs 250pF. Which is what gives the impression of mid-boost, as upper mids are passed along with treble.

[tubenit]

I use this midboost for all 3 of my amps.  And I like it ALOT!

You can calculate the values here:  http://www.kusashi.com/series-capacitors.php

With respect, Tubenit

[dscottguitars]

typo...