LeftyBassist.com

im thinking about adding a compressor to my live rig SVT 2 or GK1001rb + boogie diesel 4x10s, also sansamp di, I am looking at a dbx 160 or a mxr bass comp. Any thoughts, advice? i do want agressive compression, not necessarly transparent as they say. I dont know much about it, but when I recorded last year in a studio it made it so much tighter and punchier! I was in a rushed, didnt talk to to the engineer about what they used.

I'm not a huge compression user myself but I can tell you that you can't go wrong with the MXR that you mentioned. It's very musical. Another one that might be up your alley is the T-Rex Squeezer. It has a tube in it and can actually add quite a bit of gain as well. Lots of versatility from very mild peak limiting to full on tube growl funk squish.

I love compression on bass and have been through a few of them. I currently have the Empress and it really is worth the $259 I spent on it. I had the Diamond prior to the Empress and really liked it as well but I never used the eq function and like some of the features on the Empress a bit better. I have head good things about the MXR but haven't tried it. I'm not a pedal snob but at $175 for a Chinese made MXR, I would rather spend a bit more and go with a boutique small builder. The Diamond is about $199 I believe.The 3Leaf Pinzor looks really cool as well if you need it to be small. A good comp is a great investment regardless.

I not a fan of compression when playing live but the MXR would be the way to go. Keep in mind the type of compressors used in Studio are rack format and usually go for over $1000. They can be used in a pretty subtle way and usually used when recording most sources.
If I were you I would try one in store to make sure it is what you want. A cheap/bad compressor can ruin your sound too