That adafruit ADC has an I2C bus, not and I2S bus and will be too slow for digital audio processing. Why not use the audio shield from PJRC which provides 16bit audio inputs and outputs?
Ahh thanks for clarifying, must have picked up mis-info from seeing people mention i2c and i2s seemingly interchangeably. Or maybe because the wording seems so similar:
"Integrated Inter-IC Sound Bus" and "Inter-Integrated Circuit"!!
Both made by Phillips, kudos to them!!
I do have (as of today) multiple audio shields, the one I've been using thus far, before getting the 3.6, was stupidly soldered straight to a 3.2, no easy interchange when the .6 arrived. So I'd just explored to see if I can get a jump on the next stage by running the same code on the 3.6 without the audio shield, albeit at a reduced bit rate, but alas I found the hidden perils of trying to read a pot and get an adc listening to an audio stream at the same time!
I'm always keen to find drawbacks and limitations and figuring out how to deal with or work around those limitations.
To the ada adc, I had a suspicion it wouldn't be great for sampling audio after reading it was capable of a whopping 860 samples per second! vs audio's 44.1k might be horrible or might have that super lofi sound everyone's looking for today
After a load of reading last night one solution seemed to use this Pedvide ADC library:
https://github.com/pedvide/ADC, but having not tested it yet or read more than a few pages of forum posts I'm yet to figure out if it could be a viable solution to the analogRead blocking problem. One post about merging audio lib and Pedvide's seemed optimistic that it's possible.
I tested the code from exactly the same synth on 3.2 with audio shield and 3.6 with no a/s, I actually preferred (and not just me, I did a test with others as well) the 12bit 3.6 sound, seems fatter, more character. I wanted to carry on the experiment and see how the sound of a looper would differ, I predict there would be a similar effect and would similarly crunchify the sound in a pleasant way.