Are power ratings of A/V receivers directly comparable? (Article)

[gadgtfreek]

Answer:
The short answer to your question is...not enough information to give you a satisfying answer. The specifications you provide are incomplete, and may not be the same at all.

Let's discuss how to read power ratings for A/V receivers (AVRs) and separate amps more generally. Customarily, power rating for stereo amplifiers are specified as follows: continuous power output per channel into 8?, with both channels driven from 20Hz-20kHz, with 0.1% distortion or less. However, AVR manufacturers often provide power ratings that, while both legal and technically accurate, deviate from the customary standards to make their amplifiers appear more powerful. Some common differences:

listing "peak" or "dynamic" power rather than continuous power:
listing power at 6? rather than at 8?;
measuring power at just one frequency, typically 1kHz, rather than over the whole 20Hz-20kHz bandwidth;
measuring power with just one channel driven; and
relaxing the distortion threshold to 1% or higher.

http://www.hometheaterhifi.com/secr...ngs-of-a-v-receivers-directly-comparable.html

 

[jevans64]

A pretty good indicator of how much amplification an AVR will REALLY put out is what the actual power-handling is on the UL plate on the back of the receiver. Older amps and receivers list it as volts and amps while a lot of receivers made today list it in watts, which is basically volts times amps. There is no way a 7-channel AVR " rated " at 480 watts on the back panel will ever put out 100 watts x 7. The receiver I have lists 120 volts at 11 amps, so I know it is good for the 150 watts x 7 with all channels driven at 8 Ohms with THD of 0.05%.

There really does need to be a standard used by all manufacturers. The boutique and ID manufacturers are more truthful in their specs because they have to sell a unit costing upwards of $2000.

I know most of the high-volume manufacturers fudge on the specs but they at least make them available on-line or in the back of the user manual, which should be consulted before the bold print on the outside of the box.

 

[raoul5788]

What unit do you have? Those are pretty decent numbers.

 

[lparsons21]

Harman-Kardon used to rate theirs with all channels driven for 20-20Khz. But that made their power ratings very accurate, but it also made them look to be underpowered.

My HK AVR-247 was rated at 40W/channel under those parameters yet would blow the doors off other amps rated much higher because they used just 2-channels driven in theirs. Unfortunately HK how now changed how they present the power ratings.

 

[raoul5788]

I've noticed several manufacturers doing that. They use only the two front channels when stating power output.

 

[jevans64]

What unit do you have? Those are pretty decent numbers.

I forgot about this post with Scott working on the upgrade and all. I have the Denon AVR-5308ci with the 3D/XT32 upgrade. HT Labs rated the 7 channel output at 142 watts / channel into 8 Ohms at 0.1% THD. If that wasn't enough, I'm also running an Emotiva XPR-5 rated at 400 watts/channel into 8 Ohms at 0.1% THD. The Denon does very little heavy lifting now with most of the content still being 7 channels with the exception of a handful of Neo:X titles.

Those little Class T amp manufacturers are even worse than the mainstream AVR manufacturers. Nearly all of the Class T OEMs list their power ratings at 4 Ohms with 10% THD.

 

[mike123abc]

It is one of those marketing things where a higher number must be better... Watts per channel is one of the last things I look at when selecting a receiver.

 

[gadgtfreek]

IMO, if you are running a nice home theater or FP room and have 7.1 or 7.2, 9.2 whatever, I'd just buy an amp(s) and use my avr as a pre pro. That it just my 0.02. I do not intend on using an AVR for power again after buying my outlaw.

Sure, there are AVR's with plenty of juice, but the cost is ridiculous. I have $1600 in the X4000 and the Outlaw, plenty of juice and XT32 with dual sub EQ.

 

[jevans64]

IMO, if you are running a nice home theater or FP room and have 7.1 or 7.2, 9.2 whatever, I'd just buy an amp(s) and use my avr as a pre pro. That it just my 0.02. I do not intend on using an AVR for power again after buying my outlaw.

Sure, there are AVR's with plenty of juice, but the cost is ridiculous. I have $1600 in the X4000 and the Outlaw, plenty of juice and XT32 with dual sub EQ.

Yep. My days of shelling out $5000 for a robust AVR are over. I'll be picking up an Outlaw 7900 or Emotiva XPR-7, if it ever becomes a reality, to add to the XPR-5 when Dolby Atmos processing becomes a reality. Denon probably won't have a pre-pro but Marantz will probably follow up on the AV-8801 or maybe the X5200 will have Atmos.

 

[gadgtfreek]

Even the pre pro prices made me choke a little, which is why I grabbed an open box X4000. I wanted XT32 and no way was I spending $2000+ for just a pre pro, and if my amp fails and needs to be repaired, the X4000 can power the speakers while I wait!