This is a follow up to another thread, but I can't remember which one so I'm starting a new one. I did a comparison between the GK 700RB, the 1001RB, and the 2001RB. These were the pre production lab units of the upgraded models. Tomorrow, I'll compare the current 700RB to the 1001RB. The reason for this test was that we had reports that the 700RB was warmer than the 1001RB. That may still be true with the current model, but with the new ones, this was my finding. First I compared the 1001 and the 700. Once I got the volume between the two about even, I could not tell a difference between them at low to moderate levels. At high levels, I could guess the amp I was playing through about 60% of the time. The 700 had a slight loss in the high frequencies with a slight bump in the lows. It was really difficult to tell the difference. Next, I compared the 700 to one channel of the 2001. In this case i had a much more difficult time picking the amp I was hearing in the blind test, but ultimately found the same thing as with the 1001. Our theory is that with the 700 you're hitting the rails at a lower volume producing a "stressed amp" sound that could be construed as "warmer". I was able to produce the same kind of tone with the 1001 and 2001, but at higher volumes. In the end, the tonal differences were so minute even at high volumes, that I could not truely say that one amp was warmer than the other. So that's my findings. I'll let you know about the older amps tomorrow.