skyriderWhile I don't own the NFB 11 but I do own the 2R2 11, the Audio GD is well above the 02 catergory. Having said that I also own the EL Dac and the EL amp combo, they are the beasts in term of power but the El DAC and the EL AMP are designed for clean , fast and transparent sound while the Audio GD 2R2 is warmer and a bit slower ( more euphonic ) as tubes.
andrewdoanI too own an r2r11 and agree entirely with everything said. I would add that the current gain audiogd stuff is especially great if you need to power planars.