Demand Honest Power Ratings in AV Receivers. Join our TiP Movement!

[William Lemmerhirt]

Hey if you need 10,000 watt speakers, check with me when you're done shopping! I have a GREAT deal for you! I'm in the white van parked outside...

I’m there! Do you have sleepy candy too?

 

[panteragstk]

I’m there! Do you have sleepy candy too?

I dunno. That van looks sketchy...

 

[gene]

Going live on our Youtube Channel tonight at 11:30pm EST to discuss Inflated Power Ratings in AV Receivers and how we can combat them.

 

[William Lemmerhirt]

I dunno. That van looks sketchy...

Holy FUKK!!!!!!!!!!!!!!

 

[iraweiss]

I also signed. Please also begin testing all receivers and power amps with the standards you suggest and publish the results. By the way, having come from amplifiers and receivers where 17.5 watts per channel (Dynaco SCA-35),and rated 70 watts per channel (Marantz 2270),etc were considered more than adequate, how much power with today's speaker efficiencies is really enough? Is that 1155 watt receiver that really delivers 65 wpc ACD with low distortion adequate in today's world?

 

[hk2000]

I agree, but most audiophiles know enough not to be fooled by the inflated specs. The rest of the consumers meanwhile, wouldn't know clipping if it hit them in the ears.

 

[Verdinut]

Is that 1155 watt receiver that really delivers 65 wpc ACD with low distortion adequate in today's world?

Well, it all depends on the sensitivity of the speakers, the size of the listening room, your listening distance from the speakers, the type of music and films you listen to and your listening habits.
A good way to measure how much power you need is this:

http://myhometheater.homestead.com/splcalculator.html

 

[panteragstk]

I also signed. Please also begin testing all receivers and power amps with the standards you suggest and publish the results. By the way, having come from amplifiers and receivers where 17.5 watts per channel (Dynaco SCA-35),and rated 70 watts per channel (Marantz 2270),etc were considered more than adequate, how much power with today's speaker efficiencies is really enough? Is that 1155 watt receiver that really delivers 65 wpc ACD with low distortion adequate in today's world?

Short answer: probably not. Especially if the max power consumption number is much lower, which it most certainly will be.

Example: My Denon X4300H has a max power consumption of 710w. It has 9 total channels of amplification. Do some math and the MAX ACD number you can get is ~79wpc. I doubt that situation will ever come up in normal listening, and I like to listen LOUD.

For 2ch the output is rated at 125 W + 125 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.05 % T.H.D.)

 

[Verdinut]

Example: My Denon X4300H has a max power consumption of 710w. It has 9 total channels of amplification. Do some math and the MAX ACD number you can get is ~79wpc. I doubt that situation will ever come up in normal listening, and I like to listen LOUD.

For 2ch the output is rated at 125 W + 125 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.05 % T.H.D.)

The figure of 710W is what is provided by Denon on the back of the AVR and in the owner's manual. It doesn't represent it's maximum power consumption, but just a value which the manufacturer calculated but nobody else knows how. Gene mentions about this in the text of this thread.

This AVR uses amplifiers which operate in class AB with a maximum efficiency of about 65%. So, the 710W is less than the maximum power that it could consume at maximum output. This maximum value also depends on its power supply.

 

[PENG]

Short answer: probably not. Especially if the max power consumption number is much lower, which it most certainly will be.

Example: My Denon X4300H has a max power consumption of 710w. It has 9 total channels of amplification. Do some math and the MAX ACD number you can get is ~79wpc. I doubt that situation will ever come up in normal listening, and I like to listen LOUD.

For 2ch the output is rated at 125 W + 125 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.05 % T.H.D.)

As Verdinut said, and as Gene alluded to (when he asked for "maximum" power to be specified, that the 710 W consumption Denon/Marantz specified for their X4400/4500H and SR7012/13 may not be the "maxium", but for under a certain conditions that they did not disclose.

As for math, it does not work the way you described anyway because no class AB amplifier can have 100% efficiency. Under some slightly overloaded (above their rated output)conditions, efficiency may approach 80%, more likely between 65 to 78% for all intents and purposes. So if the Denon's 710 W is "maximum..", hopefully not, then you wouldn't get 79 WPC, but only about 60 to 63 WPC based on approx 78% efficiency, and for reactive loads like a moving coil loudpeaker, the wattage would drop by about 20% or more, so the ACD power output would probably be less than 50 WPC.

Based on Audiovision.de's lab measurements for 7 channel driven at 1% THD (assumed):

Marantz SR7012

90 W into 4 ohm, 92 W into 6 ohm

Denon AVR-X4400

99 W into 4 ohm, 83 W into 6 ohm

The two have identical PS rating, and amp sections so it is safe to assume the slight differences in output power measurements were just variance within the margin of errors.

Now if you do the math in reverse, the estimated "maximum" power consumption for those two units would be around 1120 to 1150 W, based on 1% THD, and that would seem in line with Yamaha's specified 1200 W at 10% THD for their A2070/3070. That's no good, because too much assumptions have to be made, and you wonder why we should all sign, in support of the request for manufacturers to include more detailed information in their specs.

 

[Zarkoff500]

Thank you Audioholics for promoting honesty in the AV world. It really bothers me that is has become "acceptable" to mislead an uniformed public. This is predatory behavior though I understand why AV businesses do it. Hopefully an informed consumer base will force AV companies to increase their transparency/honesty when they realize we won't accept being mislead. As Gene and others have stated, it is pretty difficult to manipulate an educated public. Now only if if AV companies would be honest about their speaker ohm ratings and sensitivity as well.....

 

[lovinthehd]

Short answer: probably not. Especially if the max power consumption number is much lower, which it most certainly will be.

Example: My Denon X4300H has a max power consumption of 710w. It has 9 total channels of amplification. Do some math and the MAX ACD number you can get is ~79wpc. I doubt that situation will ever come up in normal listening, and I like to listen LOUD.

For 2ch the output is rated at 125 W + 125 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.05 % T.H.D.)

Get a better idea of the actual capabilities with this bench test of the 4200, which I imagine is the same amp section in your 4300....https://www.soundandvision.com/content/denon-avr-x4200w-av-receiver-review-test-bench

 

[panteragstk]

Get a better idea of the actual capabilities with this bench test of the 4200, which I imagine is the same amp section in your 4300....https://www.soundandvision.com/content/denon-avr-x4200w-av-receiver-review-test-bench

I was looking for that. My post was just a VERY rough estimate (which @PENG and @Verdinut corrected) just to attempt to answer a question.

I wonder what the ACD would be for all 9 channels of the 4300? I looked and didn't find that measurement.

 

[Trell]

Get a better idea of the actual capabilities with this bench test of the 4200, which I imagine is the same amp section in your 4300....https://www.soundandvision.com/content/denon-avr-x4200w-av-receiver-review-test-bench

With the X4300 model Denon added two channels of amplification so I think the power supply is a little bit beefier, but should think it would perform similar. It must be getting quite cramped inside the X4300 and Denon also added HEOS (there is even extra heat sinks on the PCB, possibly on the HEOS), so I guess it can run quite hot.

 

[PENG]

With the X4300 model Denon added two channels of amplification so I think the power supply is a little bit beefier, but should think it would perform similar. It must be getting quite cramped inside the X4300 and Denon also added HEOS (there is even extra heat sinks on the PCB, possibly on the HEOS),so I guess it can run quite hot.

I bet you are likely right in theory. In practical term, the difference in 5,7 channel driven output will most definitely be negligible so I also bet you are right about them performing similarly regardless.

 

[lovinthehd]

With the X4300 model Denon added two channels of amplification so I think the power supply is a little bit beefier, but should think it would perform similar. It must be getting quite cramped inside the X4300 and Denon also added HEOS (there is even extra heat sinks on the PCB, possibly on the HEOS), so I guess it can run quite hot.

Then adding an external fan might be a thought if a unit runs very warm....good point on the power supply/channel count change....didn't think about that but seems Denon within a model series tends to keep the same amp sections for the most part. Be nice to have actual specs on power supplies used....

 

[PENG]

I was looking for that. My post was just a VERY rough estimate (which @PENG and @Verdinut corrected) just to attempt to answer a question.

I wonder what the ACD would be for all 9 channels of the 4300? I looked and didn't find that measurement.

Assuming the protection system was not designed to do something weird, based on past bench test measurements, my best guess is, about 70 WPC into 4 ohm, 65 WPC into 8 ohm, at 1% THD. I am guessing again..

 

[Trell]

I bet you are likely right in theory. In practical term, the difference in 5,7 channel driven output will most definitely be negligible so I also bet you are right about them performing similarly regardless.

With fewer sites doing benchmarking of receivers we'll have to bet that older measurements are representative for future models, which is not a given. The Denon X4200W, a 2015 year model, is the latest review on S&V that has a benchmark of a 4000-series Denon, so what are we to make of next year's model unless we have new measurements from someone else? Hopefully Gene's campaign gets some traction.

 

[PENG]

With fewer sites doing benchmarking of receivers we'll have to bet that older measurements are representative for future models, which is not a given. The Denon X4200W, a 2015 year model, is the latest review on S&V that has a benchmark of a 4000-series Denon, so what are we to make of next year's model unless we have new measurements from someone else? Hopefully Gene's campaign gets some traction.

It's actually a little better than you think. S&V tested the 2016 SR7011 and AVR-X3400H. The AVR-X4300H's output power should measure practically the same as the SR7011 (100% certainty). Audioholics.com measured the AVR-X3300W.

Other than that, you can still get a good idea from Audiovision.de's. They measured quite a few 2018 D&M, Onkyo, and Yamaha's models.

 

[sven1olaf]

Vote to get this stickied.