this is the first time i have ever driven 4 ohm speaker loads with the XPA-5 amp and it took them and rolled with them! this is also the first time i have ever given the XPA-5 amp such a workout! it was warm to the touch after about 1 hour and with my other 8 ohm towers it would have taken at least 2 - 3 hours to get warm.
mind you the amp is not getting hot or anywhere near it. i'm just saying i can tell that the M80v3 are pulling, no, demanding some serious power for the great quality sound they are producing! i also think the amp is happier because it's being asked to do what it was designed and built to do, produce power for speakers!...and plenty of it!