Negative ground positive ground same box?

[dennism]

Like the subject line says, I'd like to put a positive ground fuzz circuit in the same box with a more modern negative ground fuzz circuit.   Two footswitchs to choose either/or both.  Planning on just running them off batteries, so no power supply issues.   Will I still have problems with the grounds to the jacks/casing?

[trjones1]

It won't work as you described it.  However, you can get a MAX1044 chip and make a polarity reversing circuit like the one described here: http://geofex.com/circuits/+9_to_-9.htm and you'll be able to use a common ground for both your negative and positive ground circuits.

EDIT: I actually prefer the TC1044 to the MAX1044.  It works the same, it's cheaper (at least it was last time I bought one) and it's max input voltage is slightly higher at 12V.

[seedlings]

I believe you can.  Wire the PnP like this http://www.muzique.com/lab/fuzzface.htm and your NpN like normal.  You will need a 1000uF across the power on the PnP.  Also you may need a 100R~220R between the + of each pedal, so they are isolated.  I build PnP fuzz wired this way and after adding the 1000uF and an isolation resistor, they play very well with other pedals. So, it should be able to happen inside the same box.

CHAD

[Kesh]

can you not use 2 batteries to build what is in effect a +9V, 0V, -9V dual rail supply, and have each effect off each rail, with a DC blocking cap between them?

[nascarbean_97]

If you use plastic jacks, and don't connect any grounds to the box, it should work, correct?

[Gurner]

I've not built any circuits with positive grounds, so I googled it & came up with an example top see what the gig is...

http://www.muzique.com/lab/fuzzface.htm

I don't any issues if using batteries for a positive ground circuit like that ....the sleeve on the jack input for that positive ground circuit is true ground (0V)...therefore, the positive terminal of your second battery could connect to true ground (0V), this will put it's negative terminal at -9V.