Hi gang, I'm thinking of getting a GT-6B soon but i have a question regarding the preamp stage in the unit. Kinda vague, but how does the preamp stand up sound wise to a rack mount preamp like the SWR Grand Prix or Alembic F1-X? Is there a noticeable difference? As a side note, I recently saw and heard "Quantum", with Alphonso Johnson. He was using the GT-6B and it sounded just awesome, considering his basses are those beautiful Modulus basses, but his amp was the house Yorkville system, which is in need of repair.