[vince1015]

Hey everyone, I am a little confused about some ratings on my audio equipment I was hoping you all could help me out. I have the following:

HK citation 19 2ch amp- weighs about 45lbs
100wpc manufacturer rating with a 660w power supply (330wpc rating)

Marantz mm500 4ch amp -weighs about 25lbs
80wpc manufacturer rating with a 210w power supply (52wpc rating)

Integra DTR 40.1 11ch receiver -weighs about 30lbs
100wpc manufacturer rating with a 744 power supply (67wpc rating)

Now, I understand that there is nowhere near a 100% efficiency rating for these power supplies. And all of these items are what I would consider upper mid grade quality. (Maybe the HK was top notch in the 80's) but even at 100% efficiency, these guys, save the HK, are not even approaching their started power rating.
Is the HK under rated? Are newer power supplies significantly more efficient, or are integra and marantz full of crap(rated at 1ch only for a fraction of a second)?

Vincent

 

[JHAz]

As near as i can tell, at least with real signals where max power is needed for less than a twentieth of a second, steady state power draw is simply irrelevant to power output. Otoh I believe manufacturers' power ratings precisely zero. Give me third party measurements, preferably from multiple third parties. Maybe, just maybe, I will start to get suckered in to mfr claims if 3-7 of their devices come close to specs when measured by independent parties. Otherwise it's all bs.

 

[Knucklehead90]

Manufacturer's specs don't exactly lie - what they are doing is obfuscation. Most multi channel receivers will give you the specs for 2 channel output - often using a mono-tone 1kh tone. I'll give you an example using an Onkyo Tx-NR-708 since its handy. The 2 channel power specs are highlighted by me. Onkyo specs that AVR with 2 channels driven per Federal Trade Commission rules established in the 70's - this after so many receivers and amps made some spectacular claims that couldn't be measured and found to produce said specs/watts. Current FTC rules are antiquated at best since there are so many multi channel AVRs and amps these days.

Reading the Onkyo specs it tells me they bump (fluff) the power specs by running a 1khz test tone at 6 and 4 ohm loads. Per FTC rules it had better put out 110wpc into two channels into an 8ohm load with 2 channels driven at 20-20,000hz - and probably does. But FTC rules don't forbid fluffing the specs - so Onkyo uses the 1khz tone to further fluff the specs. A novice reading these specs might conclude the 708 is capable of 170wpc. It sorta is - if you don't mind listening to a 1khz test tone! And only one speaker at a time.

For years the only honest AVR manufacturer was Harman Kardon - their AVRs and receivers were rated all channels driven. Since it makes their AVRs appear to be underpowered when compared to other AVR products they quit doing that. A shame really. IMO the FTC should require all manufacturers to rate their products all channels driven into a load the amp section can maintain for a certain time period.

From the manual:
==================
Amplifier Section

Audio Inputs
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)
120 watts minimum continuous power
per channel, 8 ohm loads, 2 channels
driven at 1 kHz, with a maximum total
harmonic distortion of 0.7% (FTC) (A little fluffing going on here)
130 watts minimum continuous power
per channel, 6 ohm loads, 2 channels
driven at 1 kHz, with a maximum total
harmonic distortion of 0.1% (FTC)
(Others)
7 ch ~ 170 W at 6 ohms, 1 kHz, 1 ch driven (lots of fluff/lying here!)

Caveat emptor!

 

[vince1015]

Wow knucklehead, I learned a lot about how the numbers are conjured with regard to wattage. If I am understanding correctly, everyone is playing the same dirty game. If that's true, then the wattage ratings still give a way to accurately compare. For instance, marantz may say 80w, while integra says 100w, and even though they're both full of it, I would still be able to conclude that the integra really does put out more wattage. Is that a fair statement?

 

[Knucklehead90]

The spec that I put in bold is two channels driven - you'll see that in about every manufacturers claims for their power output as mandated by the FTC. Its the most honest numbers you are going to get from the manufacturer. After all - who sits around and listens to a 1khz test tone? Makes that spec useless. Everything past the 'two channels driven' is what I call fluff specs. Looks good but doesn't tell you anything - which is exactly what they want you to look at - after all the bigger the numbers the better - right?

There is a lot more to those number but just remember to look at the 'two channels driven' for an honest spec. I don't think there are very many AVRs made today with printed specs listing all channels driven. There are two I can think of off hand are the Emotiva Fusion 8100 and the Arcam AVRs.

To figure out how much an AVR is capable of with 5 or 7 channels driven you have to look at the power supply - but this is an inexact science. If the AVR has a total power draw of say 6 amps then you can multiply that by the voltage which in the USA is 120v - comes out to 720w. Since not all of that power is going to the amp section - the video section takes a bit of power too - lets say that leaves 600w for the amp section. 600/7=85wpc. So now we're down to 85wpc but since no A/B amp is 100% efficient due to heat loss you're probably down to 60w give or take with all channels driven. As I said - not an exact science - which is why some online AVR reviewers have bench tests to find out what an AVR can deliver.

 

[Glen B]

There is no audible difference between 80W and 100W, so not worth the time debating. Most mass market multichannel amps will meet rated power with two channels driven. Its already a given that power falls off when all channels are driven at the same time. However, in real world use, all channels are never called upon to deliver their maximum power at the same time, or you would be paying for all-channel capability you don't need. When you're watching a movie, the front channels and sub require the most power. The surrounds have little information, and the sub is self-powered. By skimping on the power supply, manufacturers are able to deliver units with the latest bells and whistles (surround modes, HDMI, networking, etc) at a more affordable cost by re-directing the savings that would have gone into the power supply into those features. This is putting more units into the hands of a wider market.

 

[MichaelJHuman]

Like many people, I often wondered at the real world limits of lower powered AVRs

I bought one of the cheapest Yamaha receivers for the sole purpose of dealing with the power question once and for all. I only care to convince myself, but will share...

I had no problems hitting any volume level I would listen at with a 400 series Yamaha AVR.

Consider average room, 8 ohm (probably well behaved) speakers, listening to maybe a max of -10 to -6 dB below reference level and a typical movie ( I believe, Cars 2.) You have a powered sub ( I hope) to handle bass duties. Your receiver's amp all draw from the same power supply well, but perhaps they are not all drawing max power at once. Also, a bit of clipping on loud scenes may not be too noticeable.

I have stopped worrying about power in quality receivers. Most people won't run out of power

Buy receivers for features, buy last years model to save money, stick with Denon, Yamaha and other quality brands, and don't worry about it. Some will (worry), of course

Even if you buy a $2000 Yamaha AVR, and I have owned a few, maybe you will get 3 to 5 dB more SPL. Heck, to save a lot of money, easy enough to drop 6 dB, it's not a lot of drop in perceived loudness

Large rooms, hard to drive speakers, routine reference level listening, desire to ruin ears with concert level volumes - maybe consider external amps

YMMV

 

[KidHorn]

For reasons stated above, i don't consider the wpc when buying a receiver. I only look at features. I have maybe 100 speakers. Some 4 ohm, some 8. I have about 10 receivers. I can drive any of my speakers with any of my receivers as loud as is tolerable. Unless you have a very large room or really want to go deaf, any receiver can play loud enough.

 

[M Code]

There are many threads and internet articles about amplifier power ratings..
But keep in mind there have been many changes in the AV market over the last 15 years..
1. On-board channels of power output in an AVR have increased, from 5 channels up to 11..
2. Today for home theater systems, 87% of the market are using a subwoofer/satellite system minimizing the low frequency demands on the AVR..
3. In the race for market share, over the last 8 years the average price of an AVR has decreased 52% forcing the brands to cut corners on internal amplifier and power supply components that drop the output power capability big-time..

Just my $0.02...

 

[FMW]

Back in the day when most hi fi amps had power ratings of 5-10 watts, people worried about power ratings. I can't imagine why they worry about it today. Amplifier power is one of the least important aspects of home audio.

 

[vince1015]

You guys obviously know more than i do, so this isn't meant to be argumentative, its an honest question: If wattage is so irrelevant, what gives with power amps then? I always thought that a larger amount of wattage was like horsepower, sure I can't blow out the speed limit sign, but i can get up to that speed much faster in a big block, than i can in a prius. I though that likewise, if you have a tremendous amount of wattage, that reduced compression and clipping while improving dynamics. So if all this is a thing of the past, and a watt is a watt, why would someone go buy a $2k pre/pro, and a $2k power amp, or any product made by McIntosh for that matter, when they can just get a Marantz SR7008 for $1600 and call it a day? I am absolutely NOT trying to stir up an endless debate of separates vs receivers, I just don't understand what the point is. MichaelJHuman is essentially saying that there is no sonic difference between the HTIB receivers and the Pioneer Elite, given similar bells and whistles.

FWIW i own a TX-NR525 (80w) as well as the DTR 40.1 (100w), both made by Onkyo, both have powered my Def Tech BP8's in the past. Not what i would call a power hungry set of towers at a sensitivity of 91db, but I can tell the power difference between the two when i throw in my Inception Bluray. Not in terms of volume, but in terms of clarity. Am i experiencing a placebo?

 

[MichaelJHuman]

You guys obviously know more than i do, so this isn't meant to be argumentative, its an honest question: If wattage is so irrelevant, what gives with power amps then? I always thought that a larger amount of wattage was like horsepower, sure I can't blow out the speed limit sign, but i can get up to that speed much faster in a big block, than i can in a prius. I though that likewise, if you have a tremendous amount of wattage, that reduced compression and clipping while improving dynamics. So if all this is a thing of the past, and a watt is a watt, why would someone go buy a $2k pre/pro, and a $2k power amp, or any product made by McIntosh for that matter, when they can just get a Marantz SR7008 for $1600 and call it a day? I am absolutely NOT trying to stir up an endless debate of separates vs receivers, I just don't understand what the point is. MichaelJHuman is essentially saying that there is no sonic difference between the HTIB receivers and the Pioneer Elite, given similar bells and whistles.

FWIW i own a TX-NR525 (80w) as well as the DTR 40.1 (100w), both made by Onkyo, both have powered my Def Tech BP8's in the past. Not what i would call a power hungry set of towers at a sensitivity of 91db, but I can tell the power difference between the two when i throw in my Inception Bluray. Not in terms of volume, but in terms of clarity. Am i experiencing a placebo?

The main thing, IMO, to know about power is the law of diminishing returns. If 100 watts of power gives you 90 dB SPL ( sound pressure) then 200 gives you 93 dB, a small gain in SPL for a doubling of power. The difference between an AVR that can put out 50 watts and a heavy duty power amp that can put out 200 watts, is 6 dB, which is more noticeable than 3 dB, but not a big difference as memory serves.

There are some benefits to beefy amps vs. lighter amps. For example, you might have one amps that can do 180 watts into 4 ohms ( 100 into 8) and another that can do 110 watts into 4 ohms ( 100 into 8.) Clearly some amps will underperform into 4 ohm loads. There's speakers that are hard to drive, due to their nature, as speakers are not fixed resistor loads. Some speakers have a rep for needing pricey power amps.

I have swapped out receiver power for 250 watts / channel of pro amp power and never heard a difference. You could say I have a tin ear, if you want, or you could also consider that I never needed the extra power.

To use the overused car analogy, a 400 HP Vette won't get you anywhere faster than an air cooled 1.6L VW bus IF you are stuck in traffic, or in a 20 MPH zone, etc.

 

[JHAz]

At any given spl (loudness) your speakers nerd a specific voltage input. More voltage is louder. Less voltage is quieter. During the silences between songs on a cd the perfect amp puts out silence- zero voltws zero watts. So by definition sometimes you really want the amp to put out zero watts.

When a movie or music is around 65dB, the average level of conversation in your room, the amp probably needs to put out hundredth of a watt. More would be louder. If you play movies at reference, a really loud movie might have dialog around 85 dB. If 65 dB needs hundreth of a watt, with your speakers in your room at your listening distance, 85 dB will require 1 watt. If the movie hits the max, in very loud moments, that's 105 dB. A hundred watts. Unless you have a subwoofer, in which case the nonsub amp might only need 50-70 watts.

 

[RayDunzl]

... Not in terms of volume, but in terms of clarity. Am i experiencing a placebo?

That is my experience too. You aren't alone.

 

[MrBobb]

what gives with power amps then

A POWER AMP does not mean it weights 300 LB and needs 220v to operate. A "separate" Power Amp just means to me a dedicated box for one purpose, and folks who care about that, tend to build it with that objective in mind, although am sure you can find cheap and ****ty power amps.

 

[Billy Boden]

I always thought that a larger amount of wattage was like horsepower, sure I can't blow out the speed limit sign, but i can get up to that speed much faster in a big block, than i can in a prius. I though that likewise, if you have a tremendous amount of wattage, that reduced compression and clipping while improving dynamics.

Sorry amplifiers don't have torque. A 100W amp will get to 20W just as fast as a 500W amp.

So if all this is a thing of the past, and a watt is a watt, why would someone go buy a $2k pre/pro, and a $2k power amp, or any product made by McIntosh for that matter, when they can just get a Marantz SR7008 for $1600 and call it a day?

They are pretty.

I am absolutely NOT trying to stir up an endless debate of separates vs receivers, I just don't understand what the point is. MichaelJHuman is essentially saying that there is no sonic difference between the HTIB receivers and the Pioneer Elite, given similar bells and whistles.

Not quite true. Different amps handle clipping differently, have different output impedance and can work better or worse with a specific speaker. There are a lot of variables.

FWIW i own a TX-NR525 (80w) as well as the DTR 40.1 (100w), both made by Onkyo, both have powered my Def Tech BP8's in the past. Not what i would call a power hungry set of towers at a sensitivity of 91db, but I can tell the power difference between the two when i throw in my Inception Bluray. Not in terms of volume, but in terms of clarity. Am i experiencing a placebo?

Maybe, but one amp may work better with your speakers than another. The amp and the speakers form a system. Some will work better than others and every combination is different.

 

[highfigh]

Back in the day when most hi fi amps had power ratings of 5-10 watts, people worried about power ratings. I can't imagine why they worry about it today. Amplifier power is one of the least important aspects of home audio.

Why would someone be interested? Ego, driving stupidly insensitive speakers and trying to hit incredible SPL, mainly.

Largely, Wattage is academic, but the ability to drive difficult loads, component quality/tolerances, circuit topology and other build materials can make a difference but sonic differences are more easily heard from a better source or preamp, IMO.

 

[turnne1]

. Most mass market multichannel amps will meet rated power with two channels driven. Its already a given that power falls off when all channels are driven at the same time..

Many higher end amps are rated at all channels driven and dont drop in multichannel operation

My Sherbourn 5/1500A benches a true 200x5...and the other two I was considering at the time...the Rotel 1095 and B&K reference( dont recall the model number) amp all would do this as well
There are many separates amps and definitely higher end ones that will bench their power rating with all channels driven
Whether you need that power is another issue..I was just making the point that there are several amps that will

Like many people, I often wondered at the real world limits of lower powered AVRs

Even if you buy a $2000 Yamaha AVR, and I have owned a few, maybe you will get 3 to 5 dB more SPL. Heck, to save a lot of money, easy enough to drop 6 dB, it's not a lot of drop in perceived loudness

A $2000 Yamaha AVR is only benching about 60-65 wpc with 5 channels driven
Yamaha's of the last 5 years, or so, are not know to be powerhouses
What was the rating of the low priced Yamaha you purchased?

The fact could have been that its rating was within 15-20 wps of a $2000 Yamaha...and so that difference in SPL possibility, with a $2K Yamaha AVR, would be negligible

There are several receivers in the $2000-2500 range that will bench 2x what the Yamaha will with 5 channels driven
Whether or not you need ( or want ) it..I guess YMMV

Warren

 

[turnne1]

3. In the race for market share, over the last 8 years the average price of an AVR has decreased 52% forcing the brands to cut corners on internal amplifier and power supply components that drop the output power capability big-time..

Just my $0.02...

true

all the Asians have left the flagship AVR market

Warren

 

[turnne1]

For reasons stated above, i don't consider the wpc when buying a receiver. I only look at features. I have maybe 100 speakers. Some 4 ohm, some 8. I have about 10 receivers. I can drive any of my speakers with any of my receivers as loud as is tolerable. Unless you have a very large room or really want to go deaf, any receiver can play loud enough.

depending on what speakers paired to what AVR and what SPL...some will clip sooner than others

I once had a Denon 4310 clip and shut down with some speakers and SPL's level that the Onkyo 875 handled just fine

Warren