hey people ive got 3 guitar cabinets all 8 ohms and my amp has 2 out puts one 8 and one 4 ohms so ive got 2 wired in parellel wired to to the 4 ohm jack and i was wondering if id damage my amp if i plugged the last 8 ohm cab to the 8 ohm output? can you use bopth out puts? or will this rob me of volume?
volume won't the issue...performance will. as in the life of your amp.

i would not run out of both of those jacks at the same time. the amp wants to see a nice simple one to one relationship as far as a load goes. running a 4 ohm tap and an 8 ohm tap at the same time just does not sound healthy to me. i know there are exceptions to the rules though....what amp is this?