DIY Mic Pre Kits, Lunchbox Mic Preamp Kits, Power Supply Kits

If I wanted to add a hi-z input to the sc-1 for plugging an instrument directly, could I build an unbalanced to balanced circuit (like Owel's listed here):

http://www.fivefish.net/diy/balanced/default.htm

And just wire the outputs in parallel with the XLR connector or will that introduce a bunch of noise? I thought maybe hooking it up like the insert jack for the sc-1 might work too...

I'm building an IO-Module (X-module) that will add the Hi-Z inputs and other features to the SC-1 pre.

The circuit you linked to won't exactly work like a Hi-Z... this is more for line level unbalanced to balanced conversion... not Hi-Z to low-Z conversion which is what you need for using guitars/bass plugged into the SC-1.

Ah ok. I look forward to the module