AVR rated with two channels driven.

[artto]

 

 

When in doubt, look at the weight of the unit.  

 

I know this has been brought up before, but what about the listed amps on the back where the power plugs in. The UL listed amps. Take this 9 channel amp (Onkyo/Integra DTA-70.1) with a listed power output of 150 W/Ch at 8 Ω 20 Hz-20 kHz, 0.05%; 2 Channels driven, FTC.  When the UL listed amps on the back is 11.7 amps.  11.7 x 120 = 1404 watts in MAX. 

 

1404 divided by 9 channels is 156 watts per channel. That extra 6 watts could be overhead...

 

In summary, amps on back of unit times 120 volts = total watts it can sustain (non-burst).   Have I missed something here??

 

"Have I missed something here??"

 

Yes. Just like the volume control on an amplifier has nothing to do with the actual power output (it's all relative), the same goes for how much current it's drawing.

 

The word "volume" control is a misnomer. It's actually a "gain" control. As the loudness of the sound goes up or down the "gain" stays the same, but the loudness (output) level changes with the input level.

 

An amplifier can easily put out more power than it's designed/rated for, or draw more current than it's rated for. The question then becomes how much, and for for how long, before audible distortion or  failure occurs. And that depends on the design and quality of the amplifier.

 

 

OK. But still, how can you have a sustained amount of output greater than the total input once the caps are discharged?

 

I'm not talking about sustained output. Music & movie soundtracks are not sustained output, they are dynamic and the peaks in any given channel are/can be sustained intermittently for short period of time, in which case the amplifier can indeed draw more current that what it says on the back of the unit. That info is primarily there so you know if the electrical circuit it's running on, generally speaking, has enough power (along with anything else that might be running on the circuit. Even the electrical circuit itself, fuse or circuit breaker included, can pass more than the rated current for short periods of time without blowing the fuse or tripping the breaker. It's more a a matter of how much and how long. The total output is never greater than the total input as that implies greater than 100% efficiency which apparently everybody except John Bedini knows isn't quite possible, at least not under these conditions.

[mustang guy]

 

 

 

When in doubt, look at the weight of the unit.  

 

I know this has been brought up before, but what about the listed amps on the back where the power plugs in. The UL listed amps. Take this 9 channel amp (Onkyo/Integra DTA-70.1) with a listed power output of 150 W/Ch at 8 Ω 20 Hz-20 kHz, 0.05%; 2 Channels driven, FTC.  When the UL listed amps on the back is 11.7 amps.  11.7 x 120 = 1404 watts in MAX. 

 

1404 divided by 9 channels is 156 watts per channel. That extra 6 watts could be overhead...

 

In summary, amps on back of unit times 120 volts = total watts it can sustain (non-burst).   Have I missed something here??

 

"Have I missed something here??"

 

Yes. Just like the volume control on an amplifier has nothing to do with the actual power output (it's all relative), the same goes for how much current it's drawing.

 

The word "volume" control is a misnomer. It's actually a "gain" control. As the loudness of the sound goes up or down the "gain" stays the same, but the loudness (output) level changes with the input level.

 

An amplifier can easily put out more power than it's designed/rated for, or draw more current than it's rated for. The question then becomes how much, and for for how long, before audible distortion or  failure occurs. And that depends on the design and quality of the amplifier.

 

 

OK. But still, how can you have a sustained amount of output greater than the total input once the caps are discharged?

 

I'm not talking about sustained output. Music & movie soundtracks are not sustained output, they are dynamic and the peaks in any given channel are/can be sustained intermittently for short period of time, in which case the amplifier can indeed draw more current that what it says on the back of the unit. That info is primarily there so you know if the electrical circuit it's running on, generally speaking, has enough power (along with anything else that might be running on the circuit. Even the electrical circuit itself, fuse or circuit breaker included, can pass more than the rated current for short periods of time without blowing the fuse or tripping the breaker. It's more a a matter of how much and how long. The total output is never greater than the total input as that implies greater than 100% efficiency which apparently everybody except John Bedini knows isn't quite possible, at least not under these conditions.

 

 

OK, then using the whole total watts in compared to total watts out is relevant if you want to know pink noise max on all channels for a sustained period.

 

On the other hand, RMS is derived from a fluctuation of frequency or averaged sort of. Burst and peak can far exceed that depending on the size of the caps and capacity of the amplifier circuitry.

 

I know amplifiers and AVR's use different methods/standards for published ratings. As I understand, amplifier rating reports are regulated, where AVR's are not.  

 

Does all that sound right?

[artto]

From what I've seen the same ratings apply to the amplifiers in AVR as in integrated or power amplifiers. FTC specs are FTC specs. Either you meet them or don't. Also from what I've seen recently, at least with consumer grade products, manufacturers often pick & choose which "FTC" rating(s) the wish to show us. Pro audio is a little different, more stringent (and honest?). The FTC doesn't appear to be too head strong in policing these issues as I'm sure they have more than enough to do with more important of today's issues.

 

Total watts in compared to total watts out tells you nothing about pink noise max on all channels for a sustained period, and it really doesn't matter. What matters is what the amplifier is delivering, in terms of total watts (per channel if pertinent), all channels driven, what the frequency or bandwidth this was performed at, and for how long. And that's where some of the magazine publications can come in handy, like Sound & Vision, because they have consistent test conditions according to FTC standards give you a better idea of what the amplifier is really capable of, and you can then make some reasonable and valid comparisons, apples to apples, oranges to oranges, instead of steak to cheese.

 

I think you might be misunderstanding what "gain" is. Different amplifiers have different amounts of "gain". Some amplifiers are more, or less efficient at producing "gain" (amplification). Gain is simply how much "in" is required to produce how much "out". A "rated" one watt amplifier can easily be driven to put out more than one watt. The question is, how much more, how much increase in distortion, at what frequency and frequency bandwidth, and for how long, driving what kind of load?

 

Here's an example, from the "old days", before the FTC got involved:

Reputable companies like McIntosh or Crown would publish honest, guaranteed performance specifications. When they said model X amplifier would deliver 100 watts per channel they meant it, and guaranteed it. Then you had the low-end "Hi-Fi" companies like Zenith that made compact portable & console units (remember those?). I had one. Zenith advertised the one I had as 140 watts. Well, that was 140 TOTAL watts. Watts per channel is actually 70. But wait, that was what was then called "peak music power". Peak music power tended to be .707 times higher than the RMS power. So now we have only about 50 watts per channel. Then, we find out they measurement was made at 1KHz. But measured at full bandwith (20-20KHz) the output was only 2/3 of that or about 30 watts. Then I found out that the measured distortion at 30 watts is several percent. At the same distortion levels that McIntosh or Crown were quoting, the Zenith (assuming it could even achieve those low distortion levels) the Zenith console's amplifier is now to half or 15 watts per channel. All the time Zenith is advertising 140 watts while a diminutive little Crown D60 could stomp its ***. And that's pretty how & why the whole FTC thing got started.

Edited February 6, 2015 by artto

[mustang guy]

Thanks artto. 

 

Speakers and amps seem to suffer from the same spin. I suppose that's why PWK carried around the BS buttons.  I wonder if McIntosh carried some BS buttons.  

[wvu80]

I also have the Onk 717, and I tried some time ago without success to find out how much power was available to my 5.1 setup, all channels driven, and using the bi-amp mode (uses the surround rears for bi-amp, so in bi-amp mode 5.1 is all that you can do)

 

From the manual:

 

> Rated Output Power
All channels: (North American)
110 watts minimum continuous power per
channel, 8 ohm loads, 2 channels driven
from 20 Hz to 20 kHz, with a maximum
total harmonic distortion of 0.08% (FTC)
125 watts minimum continuous power per
channel, 6 ohm loads, 2 channels driven at
1 kHz, with a maximum total harmonic
distortion of 0.7% (FTC)
(Others)
7 ch × 170 W at 6 ohms, 1 kHz, 1 ch driven
of 1% (IEC)

 

Dynamic Power*
* IEC60268-Short-term maximum output power
250 W (3Ω, Front)
220 W (4Ω, Front)
130 W (8Ω, Front)

Edited February 7, 2015 by wvu80

[willland]

I also have the Onk 717, and I tried some time ago without success to find out how much power was available to my 5.1 setup, all channels driven

 

This is the best I could find for you.

 

Onkyo TX-SR706 

 

 

 

Now I know we are not talking exactly apples to apples here considering the 706 preceded your 717 by four models(707,708,709).  But, the weights of each are about the same(706 = 26.9lbs vs 717 = 26.7lbs) which may indicate a similar performance with the same or similar power supplies.

[artto]

Thanks artto. 

 

Speakers and amps seem to suffer from the same spin. I suppose that's why PWK carried around the BS buttons.  I wonder if McIntosh carried some BS buttons.  

Exactly!

 

McIntosh wasn't quite so bold. LOL. But their approach to prove their point was to conduct "amplifier clinics" at their dealers where anyone could bring in their amplifier or receiver, any brand or model, & they would do a performance test on it and give you a written documented report of the results. As amplifiers got better and better at ever lower prices, not to mention the then new FTC regulations McIntosh stopped doing the clinics.

[artto]

I have an Onkyo TX-NR636 in the system right now (testing) & have to tell you I'm very impressed. I also have in hand Denon AVR-X1100W which is also pretty good but for the same price the Onkyo has more power & is more future proof regarding 4K UHD, and their own (new) room compensation routine. The Denon has Audyssey. I prefer the Onkyo. The Onkyo results are more natural sounding without as much of that exaggerated weird sound that these movie processors seem to produce. I also have a Pioneer SC-63 for comparison and an Onkyo TX-NR838 is arriving on Tuesday. I haven't really been interested in Onkyo in this price class for decades but right now they seem be the most bang for the buck/best in class.