AVR power output S&V test bench - Would the results affect your decision on you next AVR purchase?

[PENG]

Any one want to guess which HDMI avr had the highest numbers ever measured by S&V or AH, for 2 and 5 channel into 4 ohms at 0.1% thd?

 

[KEW]

Any one want to guess which HDMI avr has the highest numbers ever measured by S&V or AH, for 2 and 5 channel into 4 ohms at 0.1% thd?

I'll go with the Denon 3805! I'd be surprised if it actually is, you would think they would be some exotic high-end item that was a total level better, but who knows?
Oh, I guess you do!

 

[lovinthehd]

Any one want to guess which HDMI avr had the highest numbers ever measured by S&V or AH, for 2 and 5 channel into 4 ohms at 0.1% thd?

The usual tests I've seen from S&V don't do a 5ch/7ch test for 4 ohm, just 2ch. Was this something they did in the past?

 

[Alex2507]

Any one want to guess which HDMI avr had the highest numbers ever measured by S&V or AH, for 2 and 5 channel into 4 ohms at 0.1% thd?

It's been so long that I almost forgot the numbers but 4311 is my guess. The 4520 might be the answer.

 

[mtrycrafts]

...but I still amped 'em up because whatever this disease is, it's likely terminal. ...

Yes, it is terminal so don't bother seeing a doc to help you.

 

[M Code]

Funny you mentioned this one, it's the only Yamaha AVR I have ever owned. It is still working, though only lightly used for all those years.

My experience has been in later generation Yamaha AVRs & amplifiers they are have revised their protection circuits to a smart type.. When driven in a lab test setup into a Dale bench resistor load, they can sense this and actually put out less power into the load resistor. When driving an actual loudspeaker(inductive load) the Yamaha amplifier puts out more power...
To me this was for me hard to understand but I came across this recently when installing 1 of Yamaha's highly rated integrated amplifiers into a system. Its bench power output tests were marginal but when installed in a live system driving a loudspeaker it cranked out tons of power & SPL. There was no shortage of watts..
In the near term, having access to an AP cascade system I will try and run more tests to substantiate the data...

However knowing the Yamaha design team quite well and with their extensive experience in consumer & pro-audio applications. Here they may have outsmarted the competition by designing amplifier protection circuitry that knows the difference between a load resistor and actual inductive loudspeaker... This is another reason why I caution consumers by reading too much into bench measured specs..

Just my $0.02...

 

[PENG]

Its bench power output tests were marginal but when installed in a live system driving a loudspeaker it cranked out tons of power & SPL. There was no shortage of watts..

That is interesting but I am afraid it makes no technical sense at all. You can't put more "real power, i.e. watts" into inductive load than into resistive load. Power = V*I*Cos Ø, VI in VA, and V*I*Cos Ø in watts so for example, so if the load is purely inductve, power dissipation will be zero because cos +/-90 degree = zero and all the "watts" would be dissipated in the amplifiers. @Steve81 (unless I got the Steve mixed up..) and I have had a lengthy discussion on the power dissipation thing related to the phase angle due to reactive loads and he can explain everything better in simpler terms.

A reactive (reactive or capacitive) load that has the same impedance ohmic value as a resistive load will result in more power dissipated in the amplifier output stages and less power dissipated in the reactive load itself, but for a loudspeaker, the spl produced will be more related to the current, not the wattage dissipated in the voice coil.

If Yamaha's protective system would actually allow the real loudspeaker load that is typically reactive, to draw more current than it would allow a resistor load, then it is not smart at all, as it would put the amplifier at higher risk. I believe your findings and observations, but I am quite sure it is not because Yamaha amps can push out more "power", or current (I=V/Z period..)to an inductive load than to a resistive load if the impedance values are the same.

 

[PENG]

HD got it right, there weren't many 5 or 7 channel into 4 ohm measurements. That's why I asked people to guess.. I think the reasons the reviewers wouldn't do the 5,7 channel into 4 ohms could be:

1) Most AVR and integrated amps (even some power amps) won't do well in 7 or even 5 channel driven into 4 ohms.

2) For a few that could handle such load, the tester would still be reluctant to do it in fear of causing damage, or they don't want to bother doing it on a dedicated 20 A outlet and regulate the voltage.

Based on the data I have collected so far, my guess is that it would either be the Denon AVR-5805 CI, or the Yamaha RX-Z11. S&V did manage to do the 7 channel 4 ohm test on the RX-Z9 that is less powerful than the RX-Z11. It was able to do 207 watts at clipping. S&V most likely used a regulated power supply to hold the voltage constant.

Below is Gene's editorial notes on his AVR-5805 review:
https://www.audioholics.com/av-receiver-reviews/denon-avr-5805/denon-avr-5805-measurements-cont

In any event, I was able to achieve a 170wpc at 0.1% THD with four channels driven but noted that my dedicated 20A line sagged from 124V to 119V under this test. In reality, the AVR-5805 probably could have delivered an extra 10wpc or so in a more sterile lab environment. This test certainly proved the AVR-5805 was a true powerhouse. For the fun of it I reran this test for five channels driven and was able to achieve about 145wpc at 0.1% distortion but again watched the line voltage sag down to 110V during this test. Thus again, this amp is certainly able to deliver the full capabilities of a 15A outlet and then some! Based on the amount of power reserves available in this receiver I would venture to say if you had a stabilized dedicated line to run this receiver, it could probably drive up to 7 channels simultaneously at full bandwidth unclipped at its rated 170wpc into 8 ohms assuming an internal fuse doesn't blown first. Before you actually declare your set-up can achieve this power, consider this: The efficiency of a typical class A/B amp, such as the ones found in this receiver, is around 35-40%. Let's assume 40% in this instance. In order to deliver 170wpc x 7, it would require: 170*7/.4 = 2975 watts! For a 120VAC system your line would be required to deliver 25 amps! Unless you are running 3 phase power, or convince the power company to run 6AWG romex and up the circuit breaker from a standard 15A to a hulking 25A, this simply isn't gonna happen (no, not even with name brand separates). Not to mention the fact that UL certified products such as this one are limited to 15A power consumption at the interface connector for safety reasons. Remember this next time your friend boasts about his dedicated 7CH 200wpc Class A/B amp which sports a single line cord connection.

 

[M Code]

That is interesting but I am afraid it makes no technical sense at all. You can't put more "real power, i.e. watts" into inductive load than into resistive load. Power = V*I*Cos Ø, VI in VA, and V*I*Cos Ø in watts so for example, so if the load is purely inductve, power dissipation will be zero because cos +/-90 degree = zero and all the "watts" would be dissipated in the amplifiers. @Steve81 (unless I got the Steve mixed up..) and I have had a lengthy discussion on the power dissipation thing related to the phase angle due to reactive loads and he can explain everything better in simpler terms.

A reactive (reactive or capacitive) load that has the same impedance ohmic value as a resistive load will result in more power dissipated in the amplifier output stages and less power dissipated in the reactive load itself, but for a loudspeaker, the spl produced will be more related to the current, not the wattage dissipated in the voice coil.

If Yamaha's protective system would actually allow the real loudspeaker load that is typically reactive, to draw more current than it would allow a resistor load, then it is not smart at all, as it would put the amplifier at higher risk. I believe your findings and observations, but I am quite sure it is not because Yamaha amps can push out more "power", or current (I=V/Z period..)to an inductive load than to a resistive load if the impedance values are the same.

Can't respond now, but I will investigate further and advise back my findings..
However I will say that today...
For Europe products they are requiring certain smart functions as to monitor/control power consumption. To achieve this they are not only monitoring output amplifier load specs but input levels to the driver stages. So if a power output test is being done by feeding a constant sine wave as its input the smart software can detect this and adjust input driver stage voltages and even power supply voltages/current.

Think about it...
Works in a similar way as the VW diesel gate software did to pass emission laws...
If the amplifier is being tested into a load resistor or a loudspeaker, and the processor is smart enough to recognize either, then it can make certain software changes in driver levels.

Just my $0.02...

 

[PENG]

Not sure why you specify "past" here!

I am being cautious, because some may believe manufacturers have been cutting cost and thereby sacrificing qualities. To me, there are no clear sign of that happening, but it could be true to certain extent, or not..

 

[PENG]

Can't respond now, but I will investigate further and advise back my findings..
However I will say that today...
For Europe products they are requiring certain smart functions as to monitor/control power consumption. To achieve this they are not only monitoring output amplifier load specs but input levels to the driver stages. So if a power output test is being done by feeding a constant sine wave as its input the smart software can detect this and adjust input driver stage voltages and even power supply voltages/current.

Think about it...
Works in a similar way as the VW diesel gate software did to pass emission laws...
If the amplifier is being tested into a load resistor or a loudspeaker, and the processor is smart enough to recognize either, then it can make certain software changes in driver levels.

Just my $0.02...

Okay, that can make some sense, thanks for clarifying. So it is possible that the "smart" system knows if it is driving a loudspeaker, then even though the load is more difficult than a resistive load, but because it is not a test, but a real world music or movie enjoyment, so the current draw will be much lower on average, though the peaks could be higher, something like that anyway.............

Edit: On the other hand, then there is nothing "smart" about this because naturally most music and movie contents do not put a constant demand on the driving amp. Yamaha and NAD both bank on the dynamic nature of real world applications.

 

[M Code]

HD got it right, there weren't many 5 or 7 channel into 4 ohm measurements. That's why I asked people to guess.. I think the reasons the reviewers wouldn't do the 5,7 channel into 4 ohms could be:

1) Most AVR and integrated amps (even some power amps) won't do well in 7 or even 5 channel driven into 4 ohms.

2) For a few that could handle such load, the tester would still be reluctant to do it in fear of causing damage, or they don't want to bother doing it on a dedicated 20 A outlet and regulate the voltage.

Based on the data I have collected so far, my guess is that it would either be the Denon AVR-5805 CI, or the Yamaha RX-Z11. S&V did manage to do the 7 channel 4 ohm test on the RX-Z9 that is less powerful than the RX-Z11. It was able to do 207 watts at clipping. S&V most likely used a regulated power supply to hold the voltage constant.

Below is Gene's editorial notes on his AVR-5805 review:
https://www.audioholics.com/av-receiver-reviews/denon-avr-5805/denon-avr-5805-measurements-cont

Nice old-school information..
But doesn't really apply for the latest products and designs...
Those are dated products in the above example are >10 years old and before the availability of certain low-cost processors... Later, newer processors now available @ lower costs provide a new opportunity for the audio design engineers.
Another example, are the later technologies implemented in the Class D solutions and PWM power supplies. But note that alot of the amplifier performance improvements are more voltage related rather than current related... Largely enhanced by later HD hi-res, high dynamic range audio sources that didn't exist just a few years back....

Just my $0.02....

 

[Steve81]

That is interesting but I am afraid it makes no technical sense at all. You can't put more "real power, i.e. watts" into inductive load than into resistive load. Power = V*I*Cos Ø, VI in VA, and V*I*Cos Ø in watts so for example, so if the load is purely inductve, power dissipation will be zero because cos +/-90 degree = zero and all the "watts" would be dissipated in the amplifiers. @Steve81 (unless I got the Steve mixed up..) and I have had a lengthy discussion on the power dissipation thing related to the phase angle due to reactive loads and he can explain everything better in simpler terms.

It's the right Steve. We had talked about it for an old (2013) article on Ohms Law as it relates to audio. Some key information on the subject came from Rod Elliott, of Elliott Sound Products, who had peer reviewed the article. He provided a handy chart to show the relationship of phase angle and power dissipated at the amplifier:

Obviously more power being dissipated at the amp means a higher the likelihood that the output transistors will exceed their SOA. Of course, that may or may not be a bottleneck, and it's plausible that a smart system that recognizes its being tested vs being used under real world scenarios may cut things off earlier than expected.

 

[PENG]

Nice old-school information..
But doesn't really apply for the latest products and designs...
Those are dated products in the above example are >10 years old and before the availability of certain low-cost processors... Later, newer processors now available @ lower costs provide a new opportunity for the audio design engineers.
Another example, are the later technologies implemented in the Class D solutions and PWM power supplies. But note that alot of the amplifier performance improvements are more voltage related rather than current related... Largely enhanced by later HD hi-res, high dynamic range audio sources that didn't exist just a few years back....

Just my $0.02....

Well then, if you have the new school information, would you please link us to more 7 channel driven into 4 ohm lab measurements of any AVRs? I found one, and that was for the Yamaha RX-X9, done but S&V, but that would be old school, according to you..

 

[lovinthehd]

The difference between an ACD test of power (on the Yamaha mentioned) and actual usage just reinforces the idea that ACD ratings are only so useful, such as available power to a particular channel in real life usage compared to what's available to it in ACD situation, whether limited by power supply or protective circuitry design.

 

[PENG]

More observations from my list of 60 units tested by S&V.

- Yamaha, Onkyo and Denon, also Pioneer but only the Elite VSX94THX, were at the top in terms of 4 ohm capability, two channels driven. For 5,7 channel driven into 8 ohms, the same group would dominate the top 10, but Yamha would be squeezed out and one Rotel would squeeze in.

- Denon has the best THD figures (at the knee point of the curve) in general, but it is a moot point because we are comparing 0.042 (Onkyo RZ-610) to 0.0021 (Denon AVR-4308CI), i.e. most likely an inaudible difference by itself. Also, when interacting with different loudspeaker loads, the variance will most likely vary too.

- Ranked by SN, Denon dominates the top 20 list, 9 out of 20 were Denon, including the top 3, but again they were all excellent, the top spot AVR-4810 -112.63, vs the 20th Anthem MRX-710's 107.73. Interestingly the cheap AVR-1913 did better than the Anthem.

Overall, I think most D&M, Onkyo, Integra, Rotel, Arcam and Yamaha's AVRs measured better than the others over the years. Yamaha (flagship models excluded) did not do as well in the 5,7 channel driven test in general, but that does not seem to be an issue for real world use.

Interestingly, not that it matters, I just realize the top end Burr Brown DAC, namely the DSD1792 and PCM1792A are found in only two AVRs tested by S&V. The second best PCM1796, 1795 and AK4490 are found in the most recent flag ship models.

 

[M Code]

Well then, if you have the new school information, would you please link us to more 7 channel driven into 4 ohm lab measurements of any AVRs? I found one, and that was for the Yamaha RX-X9, done but S&V, but that would be old school, according to you..

AVRs capable of driving 7 channels continuously into 4 Ohms is a dying category..
The home theater market is changing..
If 1 wants to have the power output capability of driving multiple channels into 4 ohms they need to go with separate components, or an AVR with pre-outs and external power amplifier....
To me I like old-school components...
In fact, in my inventory I have several samples of various AVRs we have developed for major clients/brands over the last 25 years. And the majority are of the old school thinking & design, my personal favorite is a Marantz 2600, 400W x 2 into 4 ohms, scope and incredible phono preamp as I still frequently listen to vinyl.

As the market is shifting toward cinema sources rather than music sources, the loudspeakers are getting smaller along with the satellite/subwoofer loud speaker systems. Yet old school loudspeaker thinking still is attached and reserved for full-range floor standing systems. I am attached to the old school audio components just as I am with my classic muscle cars. But I fully recognize the changes the audio-video/multimedia biz is going through. In fact, I would say in another 3-5 years the majority of AVRs will all have Class D solutions, smaller footprints, loudspeakers will be invisible being in-wall or ceiling with on-board Class D amplifiers. The bulky, larger AVRs with Class A-B amplifiers will be history as now the majority of video & audio sources are being streamed.

Just my $0.02...

 

[Johnny2Bad]

That is a good point, but in many cases, both Gene's and S&V's test do show distortion numbers at very low output level.

Below are two examples:

Note that it says "The distortion level remained at or below 0.002% across all power levels until it reached about 165 watts."

Read more at https://www.soundandvision.com/content/denon-avr-4308ci-av-receiver-measurements#tZGKX051SIrqwsbb.99

https://www.audioholics.com/av-receiver-reviews/denon-avr-x3300w-1/measurements

That was just one example. If you hear something, and measurements don't reveal it, you need to explore further measurements. Static (single frequency, whether at a fixed value (1 KHz, the easiest frequency for any audio device to drive) or swept (eg 20 to 20KHz) distortion measurements combining all harmonics is of very limited value. It will only reveal the grossest of aberations. In other words simply verifying you have a very poor Device Under Test (DUT). A Intermodulation Distortion test is far more illustrative, but then again the two standard test measurements for IMD are only two static frequencies. Real music contains much more (by orders of magnitude) Intermodulation opportunities, but is far too complex to set out a measurement regimen.

The Audio Precision test instrument has a more complex IMD function available, still far from real music in complexity, but Gene does not posses one. The image you cited from Sound & Vision may have been taken from an AP or not. Faking an AP readout is common, unfortunately. But it does not look like a genuine AP test printout (see example) so at a minimum it's been massaged by the Graphics Department.

But regardless, it's not simply about distortion. There are other areas that may cause sonic issues; the point being that if you don't test for it, you won't see it, and choosing the test that reveals an audible issue is rarely done by reviewers for the reasons I cited in my post (cost, desire to limit tests to a standard suite so readers can make basic comparisons with other gear, etc).

Image:
Genuine AP Test Printout - Multi-Tone Intermodulation Distortion Test

 

[Johnny2Bad]

RE: Audio Precision Test Equipment
Just for those that are unfamiliar with the company and it's products, AP revolutionized the audio test industry with their first product, which combined the electronics required to make measurements with a PC to crunch the numbers and provide output. Prior to that, all Distortion Analyzers and other related test gear were standalone devices. For output you recorded the values shown on the machine and presented them as you saw fit. The AP outputs a distinctive readout that can be saved or printed from the PC to a standard printer.

Because it is the Gold Standard of audio test equipment, it's not unheard of to print out a result made from some other device, or even some other DUT and presented as the device being marketed, and add an AP logo to the top right corner. (Note that the Sound & Vision chart does not use a genuine AP logo, but just the letters "AP"). Since every AP device offers excellent one-click printable output, you have to actually go out of your way to present it any other way.

I am not implying that other test equipment has no value (CLIO, which is less than one tenth the cost of the lowest priced AP machine, does excellent test measurements, for example) but just that it's a matter of trust and if you don't use an AP, why would you bother implying you do, and if you do use one, why would you not print out the readily available chart? It raises doubts about the authenticity of the results. Those doubts may be unfounded, but none the less they are there.

Trust is a critical component of any audio (or anything, really) review. The whole "Snake Oil" debate, or the "DBT debate", or even the "all amplifiers sound the same" debate, are perfect examples of how both audiophiles and the general public have a trust discord with audio specialty reviewers.

 

[gene]

HD got it right, there weren't many 5 or 7 channel into 4 ohm measurements. That's why I asked people to guess.. I think the reasons the reviewers wouldn't do the 5,7 channel into 4 ohms could be:

1) Most AVR and integrated amps (even some power amps) won't do well in 7 or even 5 channel driven into 4 ohms.

2) For a few that could handle such load, the tester would still be reluctant to do it in fear of causing damage, or they don't want to bother doing it on a dedicated 20 A outlet and regulate the voltage.

Based on the data I have collected so far, my guess is that it would either be the Denon AVR-5805 CI, or the Yamaha RX-Z11. S&V did manage to do the 7 channel 4 ohm test on the RX-Z9 that is less powerful than the RX-Z11. It was able to do 207 watts at clipping. S&V most likely used a regulated power supply to hold the voltage constant.

Below is Gene's editorial notes on his AVR-5805 review:
https://www.audioholics.com/av-receiver-reviews/denon-avr-5805/denon-avr-5805-measurements-cont

No doubt the Denon AVR-5805 was the most powerful and best measuring AV receiver we've ever measured. It was an engineering marvel and elegant piece of AV gear for a much more civilized era

No way S&V did 7CH driven @ 4 ohms, nobody to my knowledge does that (including us) as it would demand too much power from the outlet and shut down virtually any multi-ch receiver. Most pubs, including us will test up to 2CH driven, 4 ohms on AV receivers.