Understanding Power Ratings in AV Receivers 

Ted Manasa sounds very honest and factual.

Totally agree with Ted Manasa above. I've been in telecommunications for years, and now engineer (Cellular biz) test systems that test communications hardware, particularly amplifiers across all radio frequency bands. After all these years I decided to get into home theater and was blown away at just how confusing the audio industry is compared to one that relies on strict FCC defined guidelines and specifications that I come from. Clearly some of this is marketing. Even "horsepower" was a marketing ploy to give farmers an idea how strong a steam engine would be compared to something the farmers understood better such as a horse. But it appears marketing has gotten a little overly creative, I can say the same thing when it comes to figuring horsepower on a lawnmower these days since a number of the manufacturers no longer apply a horsepower rating to their mowers, so I have to resort to watching videos and gather other peoples experiences using a particular mower when the grass is a foot high to determine if it is going to cut my yard. I really like that Audioholics tests these units under load and across a wide band of frequencies, even to mention the extended duty cycles imposed on the power supply by lower frequencies. Perhaps what we really need to see is an all channels loaded and driven, and power measured at each output, to 1% THD in the various modes the amplifier operates. I realize that would entail a lot of testing permutations, which could easily be handled by an ATE (Automated Test Environment) system. But probably a simpler method would be to measure the input power to the amplifier while putting it through its paces from a few to all output channels, and note where the input power seems to start clipping to determine the MCP (Maximum Composite Power) of the amplifier(s) (and the power supply limitations as well), and particularly amplifier efficiency.

Very kind. thank you.

I just purchased a 720 and they make my speaker loud and clean, first I play some songs without running the ARC. An then i run the ARC and o boy you can tell the difference right away, The only bummer is I cant play my old iPod through USB.which is i missed on my Yamaha receiver

Abbey king yea Ive heard great things about There room correction. I really want the 720 !

My rule of thumb is very simple. Divide the power supply wattage (if stated) to 3/4, (typical conventional iron plate transformer efficiency) as power supplied to the processing and amplification circuitry. Reduce the remainder to 3/4, as typical npn/pnp transistor efficiency. Eg: 800 watt power supply = 600 watts output. 600 watts x 3/4 = 450 watts total. In other words, you get slightly more than half the rated power consumption as final total output. The rest is space heating. Therefore, one would expect 90 watts rms per channel continuous, from a 5.1 receiver with an 800 watt power supply. If the device doesn't state power consumption treat all claims with caution. Toroidal transformers (up to 90% efficiency) and Class D output (typically 85% efficiency) might deliver a further 15-20% maximum output, depending on the quality and efficiency of the switching circuitry. No one listens to single channel output, so its claim should be rejected as pointless window dressing. No one would use a 5.1 receiver as a mono amp. That is a PA or bass reinforcement application only, for which one might buy a 1000-2000 watt mono or bridged stereo amp.

Great feeback, you made a great choice. Thanks Marcus.

Most manufacturers prefer to show their products in the best possible light either by massaging the specs or not showing the conditions in which the specs were taken (most usual).

Both are shit

@@ArthaxtaDaVince777 Yup. Avoid both hehe.