[pit]

What about a recording versus a live performance? Isn't a MIDI essentially a super-low-resolution digital recording, minus any spatial acoustic noise? Is soul then contained in space, or the presence of those souls present?

Here's an idea for a test: start with a song recorded at 44100Hz (standard CD quality) that has soul. We can debate the actual piece of music, but I'll use "Clap Your Hands" by A Tribe Called Quest in this example. Give a bunch of people a randomly-downsampled version of the song (at 12500Hz, 800Hz, 220Hz, etc), and have them answer a simple question: "Does this have soul?"

The song is 93BPM, or 1.55 beats per second. At a sample rate of 1.55Hz, we're looking at one sample per beat. Let's use a standard 16-step sequencer and say that a MIDIfied approximation is going to have four samples per beat (quarter notes). So, at about 6.2Hz, we've got a recording that has no better resolution than MIDI (potentially even worse).

Ultimately, I guess I agree with you: "soul" is in the ear of the beholder.

(Disclaimer: I don't actually know anything about digital audio.)