I had one of those for a while and it sounded okay with the double bass. I was using an Underwood pickup through a Fishman Pro-EQ at the time. The amp's graphic EQ came in handy and I usually shut the horn off. Some of the other features like the noise gate and the compressor were not very useful in IMO. That amp had some reliability issues for me so I sold it a while back. I now use a Gallien-Krueger MB150S or a SWR Workingman's 12 combo and I like them both better than the Carvin with a preference for the former.
BTW the new Fender Bassman 100 combo looks like it might be worth checking out (100 watts, 25 lbs.). Fender even says it's designed for upright or electric (a new marketing approach for Fender) and I have been impressed with their new Bassman series for bass guitar.
- Steve
http://kaybass.home.att.net
- Steve