.5 ohm question

if a amp says it is 1 ohm stable does that mean it is also .5 oh stable?

no .5 ohm is twice the load of 1 ohm, it may cut out on you or trip the protection circuit. You can always try it out and see.

ok i found another amp it is a mtw thunder 8001d and i know that mtx under-rate there amps, but i was wondering if you or anyone on you/ are on here have own that the birth sheet says how much they really are.

I'm not really into MTX. Best thing to do when matching amps and subs is know what you are looking for. Most class D amps are most efficient at 1 ohm, so if that's what you want to buy then look at a sub that is dual 2 ohm OR a pair of subs that are dual 4 ohm.