Update on G-MPC with Accelerator and Precision Reference ICs:
I left the fifth Galileo MPC plugged up all week and did some extensive listening today with and without the G-MPC on the Accelerator ICs between preamp and amp.
My initial impressions hold true after today's audition. The G-MPC tends to makes the Accelerator too pedestrian in my system, although it does provide more air and bloom around performers and within the soundstage as a whole. With my system balance now just a hair toward the warm side (likely the T3 UHC on my Krell amp with an otherwise very neutral configuration), to my ears the Accelerators provide a better overall balance with the standard MPC.
Accordingly, the G-MPC is awesome with the Precision Reference ICs I have on audition as it takes a bit of the edge off of the fast and aggressive sound of the PR and opens it up. Without the G-MPC, the PR produces a sound that is smaller and less expansive, much like turning off the REL sub with its magical effect on the soundstage and 3-D imaging.
It is a tough call between the Accelerator with standard MPC and the PR with the G-MPC. The sonic difference is certainly easily discernable, it's just a matter of preference. The Accelerator is just as fast, but a bit less razor sharp and a smidgeon more congested than the PR. The PR has better bass taughtness and improved immediacy but is not as musical as the Accelerator. More listening required to make a call.