How do I know the true wattage output of my receiver?

[Zman2k2]

Yeah, I figured that I'd need to get it tested, but that is of course rather expensive. Big Daddy, thanks for the formula. I may give that a shot, as I already have a decent voltmeter, so I may go searching for a few test tones to download and try out.

I don't really know why this came up, but I was just curious. I guess as Zixxer said, I wonder how alot of companies come up with the rated power of a certain receiver. I was reading the magazine, and then last night, I was flipping through the manual on my receiver, and I wondered if I'm really getting the 150W @ 6ohms that I'm currently set-up for.