I really like the Tube Driver as an overdrive effect, but yes, you have to boost the Lows and the Contour to maintain low end. I find that you can get fairly close to the same amount of the clean low end in this manner, but you cannot really boost lows. Conversely, the Blue Tube is more appropriate for use as a bass preamp, as it will allow you to actually add lows. But, the Line Driver can dial in a more aggressive overdrive. I tend to think of the Tube Driver as more of an effect, and the Blue Tube as a preamp. Both are great units, though. Tom.