Positive ground big muff

[pnadora]

I am currently building a "mother of all fuzz"-pedal with a fuzz face a mk3 tonebender and a big muff in one enclosure. I was originally planning to build the germanium ff and tb from scratch and rehouse my big muff into the new enclosure, but on the way I decided to mod it. Turns out the big muff pcb is horrible and I got lifted traces as soon as I touched the board with my soldering iron. Now I will just build the muff on vero as well and just use most of the old components. I have 2n5087s laying around that get good reviews in a big muff and since the other 2 fuzzes are positive ground as well I figured that changing the muff to pnp will not be a problem, since the negative voltage inverter is installed anyway. So my question just to be sure: I simply orient the new transistors poperly and change the orientation of the led and the electrolytic caps to turn the nyc big muff layout into pnp/positive ground, right? Does anyone of you have experience with changing a circuit from negative to positive ground or the other way around?

Thanks!!

[Travis]

You will also need to flip the battery/power supply so that the black wire (negative) connects to what is originally called "9V" and the red wire goes to ground.

[pnadora]

http://tagboardeffects.blogspot.de/2012/05/negative-voltage-inverter.html

I used this little helper to convert the voltage. Using it do I connect ground to ground and -9V to the usual 9V cable?

Thanks for the response!!

[Travis]

Yep, you've got it right!

[Muadzin]

If memory serves me right there were a few positive ground Muff schematics on the Kitrae site. Both a late Triangle and a late Rams Head.

[motterpaul]

I just built a tonebender 3 followed up by an Em-Drive in the same enclosure. In order to avoid having two volume and two gain pots I just replaced the gain & volume on the tonebender with links (like full-on pots) - it works great.

The main thing to remember when stacking pedals is that you want to make sure you don't overload the second circuit.

I suggest putting the two circuits together first and deciding whether you need have two gain controls, or if you only want one, you might want to install a pot first, and then set it for optimal sound and then measure to resistance and think about then replacing the pot with a fixed resistor of the same value.

Also - that power inverter will allow you to tap both -9v or +9v, and ground for both circuits, depending on what you need. My Tonebender used -9, but the Em-Drive is +9, but they work together just fine.