Whats this mean, at 4 ohms it runs 40X4, but at 2 ohms it runs 50x4, how do you detirmine the ohms it runs at?

 

The amp is capable of running at those 2 impedences when it "sees" it. In other words if the speaker is pushes has a 2 ohm impedence than the amp will run hotter and push more wattage, if the speaker is 4 ohm then it will run 40 watts to it to each 4 ohm speaker.

Let's say you tried to run this amp at 1 ohm impedence and it was not rated at that low stable.. you can kiss the amp good bye.

speakers voice coils determine ohm impedence and amps adjust to that impedence.

hope that helps

 

The amp may go into protection and just shut down or could blow a fuse. Doesn't nessessarily mean the amp will blow but its definatly not good for it. Oh yeah the difference between 50w and 40 isn't gonna be great. Id run it at 4 ohms so it runs cooler and probably less distortion. 10 w isn't worth it to me unless you have no choice.