Power ratings and speakers. Can you explain this one?

Y

yepimonfire

Audioholic Samurai
Klipsch uses pink noise bandlimited to the f3 of the speaker (IIRC similar to the IEC standard) with a 6dB crest factor to derive continuous/peak power handling.

Sent from my LM-X210(G) using Tapatalk
 
P

PENG

Audioholic Slumlord
Klipsch uses pink noise bandlimited to the f3 of the speaker (IIRC similar to the IEC standard) with a 6dB crest factor to derive continuous/peak power handling.

Sent from my LM-X210(G) using Tapatalk
Thank you, if true, Klipsch deserves the credit to providing more details than simply one or 2 numbers for their power ratings.

I did a search and found two more pieces of info, more credits for Klipsch.

http://www.klipsch.ca/education/speaker-specification
http://assets.klipsch.com/files/Dope_770100_v16n1.pdf

One issue I have with the info in the first link is:

"RMS as a measure of power is a misnomer. Technically it is continuous power, which represents the average power when reproducing a single tone."

The first sentence is excellent leading into hopefully more, but unfortunately they added their own misnomer in the second sentence that will likely result in further confusions. It also appeared to be contradictory to what Yepi quoted, that is, pink noise vs single tone.

We know what RMS means for voltage and current, but for power the correct term is "average power", or just "power" as stated (by Rod Elliot if I read it right) in one of many Audioholics.com article:

"When I refer to power in any of my articles, common usage shall prevail, and I (like many others in audio) will reluctantly accept the term RMS Power to mean power. All amplifier power ratings in the project pages (and elsewhere) are 'RMS' unless otherwise stated."

https://www.audioholics.com/audio-amplifier/amplifier-power-ratings

So if Rod Elliot and supposedly Gene, could reluctantly accept that, so could I, but I take issue with the word "technically, and "continuous". Klipsch has a large customer base, they shouldn't have made things worse and now we can expect when people see the so called RMS power rating of other speakers (not by Klipsch) they might be led to believe those are literally "continuous" power ratings.

Even for Klipsch speakers, they could do even better if in addition to what yepimonfire quoted, by also providing the type (is it really pink noise, or a sine wave?) and duration of the applied test signal. Without the duration, say 1 second, 2 minutes...etc., are we to interpret that as literally continuous (like forever), one cycle of a sine wave at 1 kHz, or 50 ms using a pink noise tone, what is it anyway?? Again, to be fair, the information Klipsch has provided on the power ratings of their speakers over the years are plenty, compared that of many if not most of their competitors.



 
Last edited:
CB22

CB22

Senior Audioholic
Thank you, if true, Klipsch deserves the credit to providing more details than simply one or 2 numbers for their power ratings.

I did a search and found two more pieces of info, more credits for Klipsch.

http://www.klipsch.ca/education/speaker-specification
http://assets.klipsch.com/files/Dope_770100_v16n1.pdf

One issue I have with the info in the first link is:

"RMS as a measure of power is a misnomer. Technically it is continuous power, which represents the average power when reproducing a single tone."

The first sentence is excellent leading into hopefully more, but unfortunately they added their own misnomer in the second sentence that will likely result in further confusions. It also appeared to be contradictory to what Yepi quoted, that is, pink noise vs single tone.

We know what RMS means for voltage and current, but for power the correct term is "average power", or just "power" as stated (by Rod Elliot if I read it right) in one of many Audioholics.com article:

"When I refer to power in any of my articles, common usage shall prevail, and I (like many others in audio) will reluctantly accept the term RMS Power to mean power. All amplifier power ratings in the project pages (and elsewhere) are 'RMS' unless otherwise stated."

https://www.audioholics.com/audio-amplifier/amplifier-power-ratings

So if Rod Elliot and supposedly Gene, could reluctantly accept that, so could I, but I take issue with the word "technically, and "continuous". Klipsch has a large customer base, they shouldn't have made things worse and now we can expect when people see the so called RMS power rating of other speakers (not by Klipsch) they might be led to believe those are literally "continuous" power ratings.

Even for Klipsch speakers, they could do even better if in addition to what yepimonfire quoted, by also providing the type (is it really pink noise, or a sine wave?) and duration of the applied test signal. Without the duration, say 1 second, 2 minutes...etc., are we to interpret that as literally continuous (like forever), one cycle of a sine wave at 1 kHz, or 50 ms using a pink noise tone, what is it anyway?? Again, to be fair, the information Klipsch has provided on the power ratings of their speakers over the years are plenty, compared that of many if not most of their competitors.
So if Rod Elliot and supposedly Gene, could reluctantly accept that, so could I, but I take issue with the word "technically, and "continuous". Klipsch has a large customer base, they shouldn't have made things worse and now we can expect when people see the so called RMS power rating of other speakers (not by Klipsch) they might be led to believe those are literally "continuous" power ratings.


When I read this I though ok we can says that "RMS = Continuous power" great! That would make it a lot easier to understand.

But then was like wait NO, RMS literally means the Root-Mean-Square, which if I understand correctly is the area in the sine curve. Or technical definition the "the effective value of the total waveform," which I still can't seem to get visual grasp on.

Very cool find on the Dope From Hope article! Great find!
 
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P

PENG

Audioholic Slumlord
RMS literally means the Root-Mean-Square, which if I understand correctly is the area in the sine curve. Or technical definition the "the effective value of the total waveform," which I still can't seem to get visual grasp on.

Very cool find on the Dope From Hope article! Great find!
Not quite, the area in the sine wave divided by the time gives you the average value, not RMS. As you said, RMS literally means root mean square, that is, the square root of the average of the square of the ordinates under the curve and note that average = mean. You can do it graphically, or mathematically using integral calculus.

For more details:
https://www.electronics-tutorials.ws/accircuits/rms-voltage.html

For a quick and simple one:
https://electronics.stackexchange.com/questions/40341/why-v-rms-instead-of-v-average
 
CB22

CB22

Senior Audioholic
Not quite, the area in the sine wave divided by the time gives you the average value, not RMS. As you said, RMS literally means root mean square, that is, the square root of the average of the square of the ordinates under the curve and note that average = mean. You can do it graphically, or mathematically using integral calculus.

For more details:
https://www.electronics-tutorials.ws/accircuits/rms-voltage.html

For a quick and simple one:
https://electronics.stackexchange.com/questions/40341/why-v-rms-instead-of-v-average
Hey thanks! I'll be sure to read up on this. Just curious did you get a degree in electrical engineering or have a science background? This is some pretty tricky stuff.
 
P

PENG

Audioholic Slumlord
Hey thanks! I'll be sure to read up on this. Just curious did you get a degree in electrical engineering or have a science background? This is some pretty tricky stuff.
Degree in EE.

If you read everything linked so far, including the audioholics.com ones, you will understand why I really don't like the term RMS power. Power (or avg. power) = Vrm*Irms, or Vrms^2/R, or Irms^2*R for a resistor load, but Prms, in it's true mathematical form would not be useful at all. For non technical discussion, there is no harm to interchange the terms power, average power, rms power because it is one of those widely accepted errors. As soon as you get technical, like start throwing calculations/formula around, that's when confusion arises.

Another short, simple, but good read for you:
http://eznec.com/Amateur/RMS_Power.pdf

By the way, did you read the last sentence in the dope and hope article by that klipsch chief engineer back in 1977?

"The "official KLIPSCH recommendation is still to use amplifiers rated at no more than 100 watts per channel on our systems, but that deviations are permissible in some circumstances for the knowledgeable user if he wants to suffer the consequences and be liable for the results ! So--Watch out !

D. (don) B. Keele, Jr.
Chief Engineer
Klipsch and Associates, Inc.

http://assets.klipsch.com/files/Dope_770100_v16n1.pdf
 
CB22

CB22

Senior Audioholic
Degree in EE.

If you read everything linked so far, including the audioholics.com ones, you will understand why I really don't like the term RMS power. Power (or avg. power) = Vrm*Irms, or Vrms^2/R, or Irms^2*R for a resistor load, but Prms, in it's true mathematical form would not be useful at all. For non technical discussion, there is no harm to interchange the terms power, average power, rms power because it is one of those widely accepted errors. As soon as you get technical, like start throwing calculations/formula around, that's when confusion arises.

Another short, simple, but good read for you:
http://eznec.com/Amateur/RMS_Power.pdf

By the way, did you read the last sentence in the dope and hope article by that klipsch chief engineer back in 1977?

"The "official KLIPSCH recommendation is still to use amplifiers rated at no more than 100 watts per channel on our systems, but that deviations are permissible in some circumstances for the knowledgeable user if he wants to suffer the consequences and be liable for the results ! So--Watch out !

D. (don) B. Keele, Jr.
Chief Engineer
Klipsch and Associates, Inc.

http://assets.klipsch.com/files/Dope_770100_v16n1.pdf
I did, you, "SUFFER THE CONSEQUENCES" if you put more than 100 watts into the speaker! I have read the articles here on audioholics.com and have learned a good bit. Since joining the forum, I've bought an SPL, calibrated my speakers to reference level, and leaned a lot about audio brands that I never knew existed. I totally understand why you don’t like the term RMS on the forums. For my purposes, I'm going to think about RMS like the article said, "The importance of RMS voltage and current are that they can be directly used to calculate the average power."

Random side note this article go me thinking about ham radio. That's how my interest in audio began a long time. As a kid my dad was always really into ham radio. I saw that he had bought a $120 tube for his ham radio amplifier recently. I asked him, so you like tube amplifiers better than solid-state amplifiers? He told me that solid-state amplifier are the way to go in ham radio but cost about $5000 new. Also, I remember long time ago helping them properly grounded his antenna. We had to get these 20 foot copper rod’s and get them deep into the ground. I learned a lot about grounding on that project. LOL I’ve always found it interesting how stuff works but I think I learn better when I actually see it and do it. + I’m never been the best at math either so that doesn’t help :(
 
Verdinut

Verdinut

Audioholic Spartan
Nowadays, power rating of speakers mean the maximum power you can put into them, and not continuously.

But at the time that Altec Lansing were manufacturing their transducers, they were very conservative in their power ratings. As an example, in the 1970's they released the Model 19. a two-way enclosure featuring a 15 inch 416-8A woofer and a 802 compression driver outputting sound in a 811B sectoral horn with a passive crossover at 800 Hz. While the woofer had a power rating of only 30 watts, Altec specified that this loudspeaker model could handle peaks up to 350 watts, delivering an SPL of 124dB at 4 feet then!

On the same line of thought, JBL have been stating that their speakers can handle peak amplifier inputs up to 4 times their power ratings.

However, with the audiophile stuff, it is safer not to push sound levels much higher than the specified power rating, or as stated by Klipsch people, damage to the drivers are indeed possible.
 
Y

yepimonfire

Audioholic Samurai
@PENG it would be nice if they mentioned it in their spec sheets. It would also be nice if their sensitivity specs weren't so exaggerated, although they do mention "typical in room sensitivity" in fine print.

IEC 268-5 uses pink noise for 8hrs continuous with a 6dB crest, filtered at 12dB/octave below 40hz and above 5khz (since this is representative of real music/movie content). I was assured by the engineer I spoke to (itsmyforte on avs forum) that all klipsch speakers absolutely will safely handle their continuous/peak ratings without reaching thermal or mechanical failure down to their specified f3.

Sent from my LM-X210(G) using Tapatalk
 
CB22

CB22

Senior Audioholic
@PENG it would be nice if they mentioned it in their spec sheets. It would also be nice if their sensitivity specs weren't so exaggerated, although they do mention "typical in room sensitivity" in fine print.

IEC 268-5 uses pink noise for 8hrs continuous with a 6dB crest, filtered at 12dB/octave below 40hz and above 5khz (since this is representative of real music/movie content). I was assured by the engineer I spoke to (itsmyforte on avs forum) that all klipsch speakers absolutely will safely handle their continuous/peak ratings without reaching thermal or mechanical failure down to their specified f3.

Sent from my LM-X210(G) using Tapatalk
Why do you think their sensitivity specs are exaggerated? You think they lied and said oh ya the sensitivity is -93db but really it's like 70db or something. In a perfect world you'd think they'd all just tell the truth.

"Typical room sensitivity" - how would the room affect how sensitive the speakers are?

Not sure how you'd calculate sensitivity but I've saw Gene say something about how manufactures can easily trick you into thinking the speakers/ AVRs are higher rated than what they really are as a marketing ploy. So you gotta watch out for the lingo they throw around.
 
M Code

M Code

Audioholic General
"Typical room sensitivity" - how would the room affect how sensitive the speakers are?
A typical room has its own unique acoustic footprint made up of various dips, peaks, nodes of frequency response.. So the listening room's footprint summed with the loudspeaker's frequency response is what the listener will hear. For example, the shape of the room vs loudspeaker placement, wall/floor materials hard and reflective or soft and absorbent.. In our years of experience doing home & commercial AV system installs we have often measured frequency peaks & nodes as much as +/-15dB. Often the listener thinks that running a Room EQ scheme such as Audyssey will smooth these out but in certain cases the EQ software reduces the available headroom within the DSP processor.. So in the end the listener trades off EQ correction for signal headroom..
Another example, if one is running certain Klipsch loudspeakers that utilize a horn tweeter this can tend to sound peaky with too much treble boosted high frequencies.. But if the room has drapes and carpeting this can tend to absorb and dampen the high frequencies..

Bottom line..
When setting up your listening room and positioning loudspeakers including subwoofers be open to adjust their position as to deliver the target frequency response.. Whats important in the end is what sounds best to the listener..

Just my $0.02... ;)
 
CB22

CB22

Senior Audioholic
A typical room has its own unique acoustic footprint made up of various dips, peaks, nodes of frequency response.. So the listening room's footprint summed with the loudspeaker's frequency response is what the listener will hear. For example, the shape of the room vs loudspeaker placement, wall/floor materials hard and reflective or soft and absorbent.. In our years of experience doing home & commercial AV system installs we have often measured frequency peaks & nodes as much as +/-15dB. Often the listener thinks that running a Room EQ scheme such as Audyssey will smooth these out but in certain cases the EQ software reduces the available headroom within the DSP processor.. So in the end the listener trades off EQ correction for signal headroom..
Another example, if one is running certain Klipsch loudspeakers that utilize a horn tweeter this can tend to sound peaky with too much treble boosted high frequencies.. But if the room has drapes and carpeting this can tend to absorb and dampen the high frequencies..

Bottom line..
When setting up your listening room and positioning loudspeakers including subwoofers be open to adjust their position as to deliver the target frequency response.. Whats important in the end is what sounds best to the listener..

Just my $0.02... ;)
To me it sound like the tweeters on over drive mode. So getting a good mid-range in my room seems to be some what hard even with the ARC room correction. I have in-fact noticed that using ARC does limit the head room but I still don't "need" the extra-head room.

With the software on the anthem. I've actually set the treble to -4db with the quick adjustments feature and this seemed to help a good bit on toning down the treble. The real solution would be to get a larger acoustically treated room but I'd don't see much point now as I'm planning on getting a bigger house in the next couple of years. Like you mention loudspeaker place is crucial. Due to my lack of space it's hard to get a perfect speaker placement for the 5.1 but maybe one day. :)
 
KEW

KEW

Audioholic Overlord
@CB22 ,
I have read a couple of bench tests where the sensitivity measured about 4dB less than what Klipsch claims. They are still quite high in sensitivity (compared to most speakers), but it is disappointing they chose to part company with the most common convention.
Clap your hands in the middle of your yard, then clap your hands in the bathroom for a demonstration of how the room effects sensitivity!
 
M Code

M Code

Audioholic General
To me it sound like the tweeters on over drive mode. So getting a good mid-range in my room seems to be some what hard even with the ARC room correction. I have in-fact noticed that using ARC does limit the head room but I still don't "need" the extra-head room.

With the software on the anthem. I've actually set the treble to -4db with the quick adjustments feature and this seemed to help a good bit on toning down the treble. The real solution would be to get a larger acoustically treated room but I'd don't see much point now as I'm planning on getting a bigger house in the next couple of years. Like you mention loudspeaker place is crucial. Due to my lack of space it's hard to get a perfect speaker placement for the 5.1 but maybe one day. :)
We have experience and access to many, many loudspeaker brands..
So we have our preferences but I tend to hold back my opinion pushing this subject on the forums since everyone has different ideas what sounds best to them..

To my ears, in consumer, residential loudspeaker systems horn tweeters simply too bright and I prefer the softer sounding, cloth tweeters.. But as I have commented previously the end-choice is up to the consumer. In our AV install biz we have had customers with all types of preferences so typically we will set the system up and then adjust accordingly. Also since the choice of the system components we are selling and installing is usually chosen by me, I try to steer things toward the listener's final expectations after checking out his listening room and finding out his priority for source material....

Just my $0.02... ;)
 
P

PENG

Audioholic Slumlord
@PENG it would be nice if they mentioned it in their spec sheets. It would also be nice if their sensitivity specs weren't so exaggerated, although they do mention "typical in room sensitivity" in fine print.

IEC 268-5 uses pink noise for 8hrs continuous with a 6dB crest, filtered at 12dB/octave below 40hz and above 5khz (since this is representative of real music/movie content). I was assured by the engineer I spoke to (itsmyforte on avs forum) that all klipsch speakers absolutely will safely handle their continuous/peak ratings without reaching thermal or mechanical failure down to their specified f3.

Sent from my LM-X210(G) using Tapatalk
If that's what they do that's excellent, and I do consider 8 hours as continuous for all intents and purposes. JBL apparently do the same with the pro speakers.
 
P

PENG

Audioholic Slumlord
Often the listener thinks that running a Room EQ scheme such as Audyssey will smooth these out but in certain cases the EQ software reduces the available headroom within the DSP processor.. So in the end the listener trades off EQ correction for signal headroom..
Audyssey does impose limits on the boost.

https://audyssey.zendesk.com/hc/en-us/articles/212347563-Subwoofer-setup-and-MultEQ?page=4

"Chris Kyriakakis October 04, 2011 00:07
@Bob: Yes, there are limits to the amount of boost that Audyssey will apply. These are based on the measured response of the speaker. Boosting below the roll off point is never done. Also, boosting to fill holes in the response due to normal modes is not done--it would be pointless."

It also deals with issues in the time doman/phase, so it does not rely on magnitude boost and cuts. As for trade off, yes that's expected, you don't getting something for nothing. That's also true with manual parametric EQ, or any EQ really.
 
M Code

M Code

Audioholic General
Audyssey does impose limits on the boost.

https://audyssey.zendesk.com/hc/en-us/articles/212347563-Subwoofer-setup-and-MultEQ?page=4

"Chris Kyriakakis October 04, 2011 00:07
@Bob: Yes, there are limits to the amount of boost that Audyssey will apply. These are based on the measured response of the speaker. Boosting below the roll off point is never done. Also, boosting to fill holes in the response due to normal modes is not done--it would be pointless."

It also deals with issues in the time doman/phase, so it does not rely on magnitude boost and cuts. As for trade off, yes that's expected, you don't getting something for nothing. That's also true with manual parametric EQ, or any EQ really.
Keep in mind..
Room EQ schemes do more than boost/cut, such as applying delays, creating filters.. All of these tasks draw down the available resources of the DSP decreasing its headroom.. Thats one reason, quite frequently that many listeners prefer the sonic performance with the EQ scheme switched off..

Just my $0.02... ;)
 
P

PENG

Audioholic Slumlord
Keep in mind..
Room EQ schemes do more than boost/cut, such as applying delays, creating filters.. All of these tasks draw down the available resources of the DSP decreasing its headroom.. Thats one reason, quite frequently that many listeners prefer the sonic performance with the EQ scheme switched off..

Just my $0.02... ;)
That's possible, but again, if they are half honest they wouldn't do it unless there is a net gain but you never know..
 
CB22

CB22

Senior Audioholic
Audyssey does impose limits on the boost.

https://audyssey.zendesk.com/hc/en-us/articles/212347563-Subwoofer-setup-and-MultEQ?page=4

"Chris Kyriakakis October 04, 2011 00:07
@Bob: Yes, there are limits to the amount of boost that Audyssey will apply. These are based on the measured response of the speaker. Boosting below the roll off point is never done. Also, boosting to fill holes in the response due to normal modes is not done--it would be pointless."

It also deals with issues in the time doman/phase, so it does not rely on magnitude boost and cuts. As for trade off, yes that's expected, you don't getting something for nothing. That's also true with manual parametric EQ, or any EQ really.
Wow never knew it ran the signal through phase and delays. Might as well get some guitar pedals and plug em in while your at.
 
CB22

CB22

Senior Audioholic
Maybe acoustical treatments should move up the list in the purchasing priority. Then just kill the EQ. But I remember in one of Jean's video's he did say ARC room correction "is like gold," actually one of the reasons that nudged me towards getting the Anthem. I'll try tuning it on and off tonight as see what hear.
 
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