#1
I'm looking for an amp that has good cleans for jazz, and I know one of the standards is the roland jc. Aside from the cleans, I hear it works great with effects. What exactly makes a solid state amp work well with effects?

I found a carvin sx200 solid state for $100 (cant quite afford the JC), and after doing some research, and based on what I know about carvin, I might get it. Will effects work good with this amp do you think?
#2
The JC is good with effects because it has a nice, round clean sound, not the fact that it's solid state. I can't speak for the Carvin, but used JCs can be had for very cheap (many times around $400). There's even one on the used Guitar Center website for $250 right now.
Board:
Pitchblack - Fulltone Octafuzz - Hardwire OD - Blakemore Effects Deus Ex Machina - MXR Micro Chorus - Diamond Memory Lane Jr - EHX SMMH - Neunaber Wet