Alright - beng the know it all that I am, not knowing the corret answer to this is beginning to get to me. Here's the question: If an amp is rated at 300w @8 ohms, and 600w @ 4ohms, why is a very simlilar amp by another manufacturer rated 300w @ 8ohms and 450w @ 4ohms? This is purely theoretical, but I have seen such examples far too many times to count. I have a few guesses such as efficiancy and cap/transformer size, but I am looking to the more tehnically inclined in this forum (i.e. MikeyD, BGavin) for a technical, mathematically supported answer (if possible). Thanks for any help!