I have the above 10" combo. Great little thing, sounds great, loud and has served me well. I've just bought an extension Mibass 8ohm 250w cab to run with it. Whilst the extension was on its way, I did a bit of reading up. Turns out according to what other owners say about their contact with Ashdown that, some of the combo units were shipped with 250w 4ohm drivers instead of the correct 8ohm. Sure enough, I've checked mine and it's 4ohm! So now I can't use the extension for the purpose I bought i