Harman Kardon Power Question

[PENG]

HT mag and S&V test those receivers the same way. They tested the HKAVR630 the same way they tested the Denon, Pioneer.............etc. I remember reading from another thread where someone mentioned a 20 to 20kHz will give 10 to 15% less watts than a 1kHz test. Not sure how true that is.

Ross, the problem with this power consumption thing is that most brands do not tell you what their maximum continuous power consumption is. Example:

Denon 3805 Power consumption - 7.1A
Yamaha 2500 Power consumption - 500W/650VA
Pioneer 52TX Power consumption - 480W/630VA

None of them say the figures are for consumption under maximum allowable continuous output.

Harman Kardon is the only one I know (there may be others) that specifies power consumption for both idling and all channel at maximum output. However, when they say Power consumption 1000W, they do not say it is a continuous rating neither. It could be a one-hour rating, or shorter, or longer.

You really cannot apply the 55% rule, unless you know for sure the power consumption specified is for maximum allowable continuous output. It seems that most brands (not HK) tend to specify their rated power output as high as they can get away with, but when it comes to power consumption they tend to go low in order to claim energy efficient. It may also be possible that those S&V lab measured all channel driven power ratings are not truly continuous ratings, but continuous for, say 30 minutes.

Power supplies generally do have very good short term overload capacity, as long as the overload condition is not excessive and does not last for hours. Other than that, I agree, the numbers do not add up.

I hope someone with insider's (e.g., design engineers in the hi-fi industry?) knowledge would shed some light on this topic.

 

[Ross]

Peng, I understand exactly what you are saying. This goes to show what I'm trying to get at.

Most of the major HT rags us the 1khz test, which in most part doesn't mean much. The only reason for it, is because it sets at least some minimal standard for the majority of the readers out there. It gives us some sort of litmus that we can make general assumptions from, but assumptions only.

Some try to make definitive conclusions based of off their own personal assumptions. Power consumption, line voltage, capacitance, and other misc. marketing specs are usually spun off to fit a particular theory on how wattage is dished out. These so called "internet experts" claim to definitively derive a units capabilities based off of impartial and nonconclusive figures. Anyone can do a google search and formulate some sort of grasp on power output from the various forms of amplification...big deal...

I do not claim to have any definitive answers regarding this area. I however, have formulated my own understanding on the matter throughout the years I've been in the hobby, and it is an ever-evolving understanding.

best,
Ross.

 

[mtrycrafts]

Yes. I have a NHT SW-12. Don't see why that matters. It has it's own power. I don't see what is so hard to understand. When you are using a multi-channel source, such as a concert dvd, dvd-a, or sacd with a receiver that claims 100w X 7, but not "all channels driven", the mains WILL NOT have 100w available.

But it will deliver full power to the mains at rated power and less to the others at those instances. But not to worry, you will not see that day.
Music is too dynamic for all the stars to line up at the same instant.
So, you will have the power needed.
And, since you have subs to handle th epower demanding lows, I just don't see how you would need so much power to the other speakers as that would be well over 120dB spl in most cases?

 

[mtrycrafts]

This was a question. Note: The question mark.

As far as testing goes, I believe "all channels driven" is the best out of all listed. At least you know the amp was fully taxed. And as far as 1k, could you imagine listening to your favorite tune with only the 1k frequency being produced? Talk about a realistic situation.

Again, music is dynamic. You will never see full power needs to 20kHz, never. So you can throuw that out. No instrument will do it. Besides, you will not even hear it.

And, the other frequencies will not tax it simultaneously, never. You could skip 19kHz as well, right.

 

[zumbo]

Again, music is dynamic. You will never see full power needs to 20kHz, never. So you can throuw that out. No instrument will do it. Besides, you will not even hear it.

And, the other frequencies will not tax it simultaneously, never. You could skip 19kHz as well, right.

I am not sure I get this response, so I wanted to be sure I was clear. The 1k test is BS!

But it will deliver full power to the mains at rated power and less to the others at those instances. But not to worry, you will not see that day.
Music is too dynamic for all the stars to line up at the same instant.
So, you will have the power needed.
And, since you have subs to handle th epower demanding lows, I just don't see how you would need so much power to the other speakers as that would be well over 120dB spl in most cases?

Please show me proof of a receiver that is not rated "all channels driven" @100w X 7 to produce 100w to the mains while all 7, or even 5 channels are utilized! Let me save you the trouble. You are not going to find it!

I have said this before. I have peak output indicators on my amp. They work. Meaning, I use them. And believe me, during a concert dvd, I have all five channels lighting up like lights on a christmas tree! The stars do line up my friend!

My speakers are 4ohm with a sensitivity of 87dB. This is why I need the power!

 

[Ross]

"My speakers are 4ohm with a sensitivity of 87dB. This is why I need the power!"

No doubt buddy!

Ross.

 

[toquemon]

I recently acquired a HK AVR 70 old receiver rated at 80 watts RMS, 20-20,000hz, with no more than 0.09% THD. I paired it next to my Yammie RXV1400 (110 watts RMS, 20-20,000hz, 0.04 THD) and it sounds the same to me, with a little more defined bass extension (the HK). The Yammie supposed to have a high current design too, the transformer is bigger than the HK; no big difference at all. I'm still thinking that the "all channel driven" argument is a waste of time because you don't need it. What you need is a high current design that allows the receiver to handle some deep passages on music and movies for a sustained amount of time. That's why i'm using the HK to drive the fronts and the Yammie to drive the center channel and the surrounds, i think it provides some releaf to the Yammie.

 

[annunaki]

Back in 2001, S&V tested the yamaha rxv1000 ("320 watt power consumption) at ~80x5. How do you explain this... According to Annuaki, with his global ~55% efficiency theory, this sort of occurence should be impossible, defying the laws of physics. The tested unit would be putting out more than its "rated" power consumption, 400 > 320...

Anyone?

best,
Ross.

Ross,

In no way did I ever say that the 55% efficency figure was global, or applied to all receivers. However, for most receivers with a class A/B amplifier design, efficency (at full power) is typically around 50%-55%. Sometimes slightly higher or lower depending upon the bias. Some of the new "digital" receivers with full range class D amplifiers the efficency can be around 80%.

Power consumption, as I have read into it more definitively, is not a 'be all end all' spec. As I am found, some manufacturers are now rating the power consumption on many of their products for "typical use". Meaning watching a movie with and average volume of around 70db-80db (at the listening position). For a 7 channel receiver, when figured (with speakers of say about 88db-90db sesitivity) results in about 10-16 watts a channel if all were running. Which, in turn, results in a fairly low consumptionfigure. To me, this is not the best way to do things, but I do not make the rules. I still stick to my guns and will say that I prefer a receiver rated with all channels driven. I then know what the receiver is capable of at its limit. However, that is just one man's opinion.

 

[mtrycrafts]

[=zumbo]I am not sure I get this response, so I wanted to be sure I was clear. The 1k test is BS!

I don't think that is what I said. The 20-20khz is not really that useful as you will not get full power at 20kHz while playing music, no musical content at that level, nor at 19kHz.




Please show me proof of a receiver that is not rated "all channels driven" @100w X 7 to produce 100w to the mains while all 7, or even 5 channels are utilized! Let me save you the trouble. You are not going to find it!

Amps don't shut down their other channels if and when the front two are at full power that is also rare to occurr simultaneously. Hence, you will have power to the other channels.
Besides, full power is rated at a certain THD level. You do have life above this miniscule rated levels where usable power is available. You better believe it. So, indeed the other channels are receiving power.

I have said this before. I have peak output indicators on my amp. They work. Meaning, I use them. And believe me, during a concert dvd, I have all five channels lighting up like lights on a christmas tree! The stars do line up my friend!

All five channels indicating full power at the same instant? Are thesse meters or lights? How accurate are they? Perhaps they are not at full power when they are lit? Maybe some lag behind the others? Lots of maybe.


My speakers are 4ohm with a sensitivity of 87dB. This is why I need the power!

87 dB spl is loud. At 100 watts you would be getting 107dB spl to all speakers? At the same instant? You do like it very loud. Yes, those speakers are very demanding.

 

[zumbo]

They light up when distortion level reaches 1% indicating peak level has been reached. The mains light-up a little before the rest. But all light-up during musical peaks. To me, this indicates all channels are at their peak. I would believe this would be as close to "all channels driven" as you can get.

I have learned this information from this forum and I believe it to be correct. I am in no way trying to have a dispute. This is all a learning experience for me.

This is not a statement I made: "Amps don't shut down their other channels if and when the front two are at full power that is also rare to occurr simultaneously. Hence, you will have power to the other channels."
"Besides, full power is rated at a certain THD level. You do have life above this miniscule rated levels where usable power is available. You better believe it. So, indeed the other channels are receiving power."

I said the mains would not recieve 100w each while in 5 or 7 channel ues on a receiver that is not rated "all channels driven".

 

[PENG]

I said the mains would not recieve 100w each while in 5 or 7 channel ues on a receiver that is not rated "all channels driven".

You are right, the mains would not receive 100W each simultaneously. The question is, how often will you have music or movie program that sends signals to all 7 channels at the same time and at the strength that would drive each channels to 100W for sustained period of time.

If you are talking about "peak", doesn't it then imply it will be for short duration only. If it is for short duration, then I would say even the Yamaha RX-V1400 (tested to deliver less than 50W all channel driven) should have no problem delivering 100W to each channel at the same time. When HK specifies all channel driven power, say 55WX7, they mean 55WX7 continuously. This (continuous) is what a lot of us say is not necessary.

In fact, if it is (which it isn't) only for the sake of power, I would take a 130WX7 such as the RX-V2500 before I would take a 75WX7 HKAVR630. With the RX-V, I will get more powerful amps, each can deliver at least 130W, whereas with the HK, I will get a larger power supply, therefore more "all channel driven" power, but each amp individually will be only good for about 85W at clipping.

Zumbo, I am not trying to argue with anyone here neither. Just trying to learn something... In the example I used, the HK may have more all channel driven power, but the Yamaha will be less likely driven to clipping for most commonly available music and movie programs. Let me know if my logic is wrong. Thanks!

 

[zumbo]

You are right, the mains would not receive 100W each simultaneously. The question is, how often will you have music or movie program that sends signals to all 7 channels at the same time and at the strength that would drive each channels to 100W for sustained period of time.

If you are talking about "peak", doesn't it then imply it will be for short duration only. If it is for short duration, then I would say even the Yamaha RX-V1400 (tested to deliver less than 50W all channel driven) should have no problem delivering 100W to each channel at the same time. When HK specifies all channel driven power, say 55WX7, they mean 55WX7 continuously. This (continuous) is what a lot of us say is not necessary.

In fact, if it is (which it isn't) only for the sake of power, I would take a 130WX7 such as the RX-V2500 before I would take a 75WX7 HKAVR630. With the RX-V, I will get more powerful amps, each can deliver at least 130W, whereas with the HK, I will get a larger power supply, therefore more "all channel driven" power, but each amp individually will be only good for about 85W at clipping.

Zumbo, I am not trying to argue with anyone here neither. Just trying to learn something... In the example I used, the HK may have more all channel driven power, but the Yamaha will be less likely driven to clipping for most commonly available music and movie programs. Let me know if my logic is wrong. Thanks!

Now that answer makes sense. I am, as I said, learning. I would, however, like to know which amp section you would choose if the Yam & the H/K were both rated 130WX7? This is what I am getting at. Wouldn't the H/K have more powerful amps with a larger, or at least the same size power supply? Meaning, when H/K claims the same 130X7, isn't it more?

 

[PENG]

In that case, no question, HK. Expect to pay top dollars. A 130WX7 HK receiver, if exists, would probably run you the same price as a Denon or Yamaha flag ship model that rate their power outputs at something like 150W to 170WX7. Once price is taken into consideration, then I would again, take the Denon or Yamaha flag ship for the more powerful amps. My point is, at a given price, you either pay for the more powerful amps, or larger power supplies. More specifically, I agree with you that a HK 130X7 will give you more than a Yammie 130X7 ever will, but a HK 75X7 will not. If you want the best of both, go separates.

 

[Ross]

"Power consumption, as I have read into it more definitively, is not a 'be all end all' spec. As I am found, some manufacturers are now rating the power consumption on many of their products for "typical use". Meaning watching a movie with and average volume of around 70db-80db (at the listening position). For a 7 channel receiver, when figured (with speakers of say about 88db-90db sesitivity) results in about 10-16 watts a channel if all were running. Which, in turn, results in a fairly low consumptionfigure. To me, this is not the best way to do things, but I do not make the rules. I still stick to my guns and will say that I prefer a receiver rated with all channels driven. I then know what the receiver is capable of at its limit. However, that is just one man's opinion."

Holy $hit!!!

Big A, you and I finally reached a common ground on this issue.

I hope it only gets better from here on.

best,
Ross.

 

[armaraas]

Over the last month I have listened to a Yamaha 5790, HK 630, HK DPR 1001, and an HK 235 in home. The 5790, per Best Buy's websites, is 140w per channel. During my time spent with these receiver in home, the HK 630 was able to produce more power/volume than the 5790. Both the HK 1001 and 235 are rated at 7x50w, both of these were able to at least match if not slightly outperform the 5790 while listening to 5.1 when it came to volume. I would not discount the 630 against the 2500 if you ware looking at running 5 or 7 channels. If you are considering mostly stereo, then the 5790 has an advantage.

 

[PENG]

According the Yamaha site, the 5790 is rated for 110W per channel not 140W.

 

[armaraas]

Yah, I know. I went to their site to try to figure out where Best Buy was getting their numbers from. I still don't know.
http://www.bestbuy.com/site/olspage.jsp?id=1077626340181&skuId=6304778&productCategoryId=cat03031&type=product

 

[toquemon]

The Yamaha is rated 140W at 1Khz (not from 20 to 20,000 hertz, which is the standard)

 

[Votrax]

The Best Buy website is incorrect.
http://www.yamaha.com/yec/products/HTIB/HTR5790.htm

 

[armaraas]

I went through the 5790 manual thinking it was the 1khz rating, but I never saw a 140w figure listed. They list 145, 165, and 185, but not 140. I just found it odd that BB uses that number so much when there's no documentation for it.