Cosmopolitan increased voltage for line level use

[pdub]

Hi

I love the sound and functionality of the Cosmopolitan and would like to modify the circuit to use with line level sources. Ideally I'd make 2 in a box to use in stereo.

First I'd like to raise the operating voltage to 15V and then adjust the input and output impedance if necessary. I assume I need to change the 9v zeners to 15v? I would also change the input resistors to better deal with line level impedance?

Here's the schematic link. Any help is greatly appreciated. Thanks!

http://www.madbeanpedals.com/projects/Cosmopolitan/docs/Cosmopolitan.pdf

[stecykmi]

it would probably be easier to attenuate line level signal to instrument level and boost it back up afterwards. this avoids the hassle of having to remake the power supply. you could use a simple booster on the output, the SHO would probably work.

[pdub]

Hi. Thanks for your response.

Since the new unit will be built from scratch with the new voltages in mind I'd rather figure out how to run it off 15V and not attenuate the input signal too much. The input stage is very similar to the Jack Oram MOSFET booster. There's are mods section on the booster page that states it can run safely up to 18V as is. If the 9V Zener is ok with the higher voltage I don't see it being a problem for the AC127 and BC109.

Any thoughts on this?

I'm going to test 15V on my Thunderpuss and then on my Cosmo pedal. I'll report back.

Thanks

[pdub]

I'm happy to report the Cosmo runs great off of 15V without any mods. Much more headroom available for higher level signals.