If you can hear reverb on it, it's from the physical spaces I was in. (No digital reverb present at any point.)
Good examples would be the starting gong sound (recorded in a brewing kettle) and the filing cabinet jam around 14:30.
The piece was then assembled from hours or source material in cool edit pro. Some things, like the drums and guitar drones were recorded in my bedroom. At the very end you can hear garbage trucks passing outside, 20-30ft from my bedroom window - that's how sensitive the mics are.
I could have gone back and recorded the final mix in one of the buildings used, but I generally don't like applying one constant effect on a dynamic piece of music. If it was a pure drone, perhaps. I wanted the percussive elements to stay dry.