I run everything into a small Behringer mixer - 
out to a BBE sonic Maximizer and then send the 
two signals to two small Hartke kickbacks.  The 12"
model easily covers the 5th string of my bass guitar 
w/out distorting at all.
The fidelity would be better if I chose the small keyboard
amps, which I'll prob upgrade to but, the BBE cleans
it all up amazingly.  Presto - a tiny PA I have no
trouble moving around.  
The great part is that the Hartke has everything in it;
EQ, tone and a limiter! And of course w/ the Kickback 
cut of the box, it's easy to position for any situation.
I'm even thinking about drilling holes in the bottom for 
stand mounts.  
Andy