Merlot — sound before / after
The same cue, played through the old signal path and the new one.
Use headphones. The new path uses HRTF, which is a model of a head —
it works by the tiny timing and filtering differences between your two ears,
and speakers hand both ears both channels, which throws most of it away.
Before: volume by distance, left/right pan, nothing else.
After: the same, plus a lowpass that closes as the sound gets further
away and a send into a synthesised room that opens as it does.