Balanced output from audio shield

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Beavis

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I've been looking over the Audio System Design Tool, and under the Mixer section, the gain command says ,"Negative numbers may also be used, to invert the signal." If I have a mono signal on the left output channel, could I then use a mixer element to invert the signal to feed the right output channel and have a balanced output? Often equipment uses TRS phone plugs to carry balanced signals instead of/in addition to XLR connectors, would this method do the same? Would I need to have the mono signal feed two mixers (one unchanged, one inverted) to avoid timing errors, or would just the one mixer (for inverting) be OK?

I've got all the hardware for my project chosen, so I'm going to order an audio shield and a Teensy, but I'm wondering if a T3.2 will be adequate if I'm just going to use: USB input > mixer (for stereo to mono and gain adjustment) > filter (to roll off the bass) > mixer (for balanced output) > analog output (L & R channels) and also: analog input > mixer > USB output.
 
IIRC, each audio block device adds a delay of 512 samples or 11.6ms. Thus you'd have to use 2 mixers in parallel, one inverting and one non-inverting.
 
OK, thanks, and the 11.6ms number is good to know. And by "audio block device", do you mean any/every item that gets dragged from the left side menu into the editing area? So if I just had, say, USB input > spdif output that would be 23.2ms of latency? Or does "audio block device" only apply to things that actually perform some kind of manipulation on the audio stream?

Would the Teensy 3.2 handle most basic audio projects (ones that don't use AudioFilterBiquad or AudioFilterFIR)? And with my simple [stereo to mono] + [gain adjust] + [high pass filter] project, I can also use digital pins to read "up" & "down" button presses from the user to control audio parameters (like the level on a channel in the mixer) in real time? I know these questions must seem obvious (ie dumb), but I need to nail down the details and avoid any surprises since this project is for my employer.

Thanks for the quick reply and your robust patience! :)
 
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