HK vs. Denon receiver power rating

VSchneider

I have been looking for a new receiver to replace my Onkyo 502, but I am struggling to understand power ratings put out by manufactures.

I was checking some Denon and HK models going for less bright and more accurate sound. But is HK the only mainstream company that truthfully quotes their power specs?

HK AVR 245 is rated at 50 Watts into 5 channels, which makes sense given its max 540W consumption.

Denon AVR-887 or its AVR-2307CI twin is advertised as being 100 Watts into 7 channels, which is even less than the power it consumes (!!!) – max 5.5 A or 660W. Am I misreading the numbers or they are so dramatically inflated? Is Denon just plain lying in our faces?
Even my meager $250 Onkyo’s power is quoted more realistically as 75Wx7 with max 550W consumption.

All power numbers I saw were quoted 20-20k Hz with .08% or less distortion into 8 Ohms, so no games here at least.

Any advice?

Regards,
Val.

Porter

You're misreading the numbers because they don't apply. Maybe in a current-tap style Class A amp, but that's not what you're looking at.

Wattage from the wall at 60Hz has no almost no relationship to output musical program wattage at variable frequency 20hz to 20khz.

The thing you SHOULD look out for is rated wattage at only one peak frequency, i.e. 100W @ 1khz rather than 100W across the full audio spectrum. I see you've already noted that, but it's worth saying again for the folks that may be reading.

Peak-to-peak amperage is a more significant number, anyway.


And just to throw another wrench into the thought process... I've heard tube amplifiers of less than 10Wpc that would play loud enough to pressurize the air in a room. There are "200Wpc" home receivers that can't do that.

McLoki

VSchneider wrote:

All power numbers I saw were quoted 20-20k Hz with .08% or less distortion into 8 Ohms, so no games here at least.

Another part of the spec is that power number is with how many speakers running? My onkyo 777AVR was rated at 110wpc, but that was with one channel running a 2k test tone. Not very realistic in my book. Of course, before I actually knew what that meant, my opportunity to return the AVR was already over so I guess the marketing worked.

oh well - both are good recievers. I would say HK has the edge on power, Dennon has the edge on user interface and usability.

Those are just my opinions though.

Michael

VSchneider

I was looking more for cleaner power, than more of it, since Onkyo can already play loud, but I thought if the receiver (or amp for that matter) is rated higher it should be able to play cleaner below its max, correct?

My receiver doesn't have pre-outs, so the only way up for me is a new one.

Porter wrote:

You're misreading the numbers because they don't apply... Wattage from the wall at 60Hz has no almost no relationship to output musical program wattage at variable frequency 20hz to 20khz.

I thought Watts are Watts as in "Voltage times Current", or since speaker resistance tends to change with frequency played (I think this is where you are comming from), I should say "Current sqared over Resistance". In any case, don't you need energy from the wall for sound amplification? I am pretty sure they use class AB amps with 50-75% efficiency, so they output at most 75% of what they consume?

Porter wrote:

Peak-to-peak amperage is a more significant number, anyway.

Could someone ellaborate?

- Val

VSchneider

McLoki wrote:

Another part of the spec is that power number is with how many speakers running?

I have looked at that, too. HK AVR 245 is a 7 channel receiver obviously, but its power is rated with 5 speakers playing.

aba4430

Read this. There is also a pdf file (Pioneer article) on Power ratings.
http://www.polkaudio.com/forums/showthread.php?t=43094&page=2&highlight=aba4430

jakelm

Look at my H/K power ratings. Notice with 2 channels driven it 90watts per channel 20-20k @ 8ohms. Then notice with all seven channels driven its 75watts 20-20k @ 8ohms. That is what I look for.

Stereo Mode
Continuous Average Power (FTC) per Channel : 90 Watts per channel, 20Hz – 20kHz, @ <0.07% THD, both channels driven into 8 ohms
Seven-Channel Surround Modes, Power per Individual Channel,
All Channels Operating at Full Power :
Front L & R Channels : 75 Watts per channel @ <0.07% THD, 20Hz – 20kHz into 8 ohms
Center Channel : 75 Watts @ <0.07% THD, 20Hz – 20kHz into 8 ohms
Surround Channels (L & R Side, L & R Back) : 75 Watts per channel @ <0.07% THD, 20Hz – 20kHz into 8 ohms

Ron Temple

HK does there numbers differently than most receiver companies. It is indeed 50 X 7 simultaneously, through the entire spectrum 20-20k. They actually do a bit better than rated. The 235 drew 890 watts, not 540. Either the Denon or HK will be a step up from the 502.

jakelm

Ron..lol...Looks like dejavue when I was comparing my onk 502 to my H/K635 not long ago.

VSchneider

Thank you everyone for replying.

Jake, I found your HK vs. Onkyo 502 thread. This should be an interesting lunch read!

That Pioneer pdf article should be mandatory for all new Polkies. I remember seeing something similar but less detailed here in the FAQ section, too.

Ron Temple wrote:

... Either the Denon or HK will be a step up from the 502.

Thanks Ron, I see a definite step up in features and price, but was hoping not to move sideways in performance.

Val

Refefer

I guess the question I have is why not go separates? That will certainly give you much cleaner power for an acceptable amount of money with far more flexibility than a receiver alone will give you.

John K.

Val, yes you're misreading the numbers, basically due to the fact that power consumption figures aren't maximum consumption(as you seem to assume)unless specific language such as "maximum" or "full power" is used. Otherwise, the consumption rating is an average consumption at less than full power. For example, the most common average is taken with all channels driven at 1/8th of full power. That may seem odd, but its from a UL(Underwriters Laboratory)required safety test for overheating which is taken at that power and is said to roughly correspond to the average power used over the entire course of a CD. Class AB amplifiers which most receivers use are about 50% efficient at full power, but efficiency is less at lower output levels and is around 20% at 1/8th power. So, looking at a 7x100 watt unit with a 450 watt power consumption rating, we see that 1/8th of 700 is about 90 watts and since efficiency is about 20%, 450 watts are consumed, and there's no inconsistency between the numbers.

All receiver/amplifiers sold in the U.S. have to comply with FTC(Federal Trade Commission) regulations for power ratings, which basically require that at least two channels are driven simultaneously at full power for at least 5 continuous minutes. Manufacturers would be foolish to violate the law, and the published power ratings are accurate, although some manufacturers(e.g. HK) are conservative in stating their test results.

Your 502 is excellent within its designed power limits and provides audibly transparent amplification. If you're looking for clean power, rather than more power, you've already got it. Receiver/amps with higher maximum power ratings don't provide benefits at lower power; unused maximum power capacity is simply that: unused.

reeltrouble1

Anti Hi-Fi Insurgent sighting.

The power supplies, printed boards, circuits, etc. found in the receivers you mention are a compromise to convienence. Although they actually sound pretty good for the cost, if you want more clean power you need to consider the ampre rating of the amplfier, how much current can flow.

You will do better with a seperate pre/pro and multi-channel amp, or at least a two channel amp to run the fronts, if you must get a receiver ,yes as you said, get one with with pre-outs and you will be able to add a more powerful amplifier later.

For practical experience I have a 502 onk and a H&K 240 serving as bedroom units, the H&K has a bit better sound to my ear with my gear in my room. And yes you need the power even at moderate listening levels.

What speakers are you using? How effecient are they? How large of a room? All figures into the mix.

RT1

VSchneider

Thanks, John, this clarifies a lot.

RT1 and Refefer, I have thought of using separates, but that’s a little more than I wanted to spend right now. I wouldn’t mind a separate 2 channel amp for stereo, and then I will definitely need another receiver.

My room is 19x20x8.5, and the speakers are RTi6, CSi3 and FXi3 + a Mirage S10 sub. I did use another speaker in the back, but with FXi3 I actually prefer the sound in 5.1. The most I have gone on the volume dial is about 12 o’clock (maybe 1-2 once or twice), but I do occasionally wish I had just a little more for music.

The other reason I was thinking of a Denon or an HK is that I find I usually turn down highs and raise lows by 1 or 2 dB each on my Onkyo for most music and movies; that’s the only EQ option it provides. From what I have listened and read, either of those other two will sound slightly less bright. I have yet to do a direct demo with Onk, HK and Denon in the same room on the same speakers. My local Circuit City is finally getting the listening room that once finished should be able to do just that.

With your good compliments to the 502, I think I am better off using it for now, and will move on to one with pre-outs once I get a 2 or 5 channel amp. My wife, as much as she’s supportive of my hobby, will be glad I am not bringing home more hardware. I just bought an upconvering Denon DVD player, which is my favorite new toy for now

Again, thank you everybody for help!

Val