[KeithEmo]

You seem to insist on treating certain generalizations as facts - while discounting others disproportionately.

As a few other people have noted, you can't get a true square wave out of digital audio at all - due to band limiting.
However, in order to be potentially dangerous, you don't actually need an especially good approximation.
For example, many popular speakers have a crossover between 1 kHz and 3 kHz, and second order, and even third order high-pass filters, are actually quite common.
So, if I start with a 1.5 kHz tone, as a pure tone it will be handled by the midrange, but even the first harmonic present in a vague approximation of a square wave (the third harmonic - at 4.5 kHz), will fall squarely into the tweeter.
And, since it is also relatively common for tweeters that are used above 3 kHz, with a third order filter, to have rather low power handling capabilities, this can be significant.
And, yes, you do have to clip the signal "pretty hard" to generate any significant power in the harmonics...
Because of this, it probably is far more likely that a speaker will be damaged by the high average power level of a heavily clipped signal than because of its spectral content.

The general way I've heard the assertion is "people with low powered amplifiers, who turn them up until they clip, in an attempt to get them to play loudly, are more likely to blow tweeters than people with more powerful amplifiers".
The assertion I'm familiar with is NOT that people with more powerful amplifiers are less capable of blowing tweeters if they make bad decisions - just that they are statistically less likely to do so.
And, while that may not always, or even necessarily, be the case, most people in the industry agree that it often is.
Incidentally, most companies are not able to collect data about exactly why tweeters get blown (customers tend to avoid admitting that they drove their amplifier into hard clipping, because that would count as abuse, and might void their warranty).

The reality is that people routinely harbor the belief that "if they have a 100 watt amplifier and 200 watt speakers they don't have to worry about how loud they turn up the amp because it isn't powerful enough to hurt their speakers".
And this frequently ends up being proven wrong by the practical lesson of a blown driver.

I would also disagree with your assertion about amplifier power (unless you're simply suggesting that "most people have at least a reasonable amount of power these days - which I tend to agree with).
We still routinely see AVR and smaller amplifiers in the range between 20 watts/channel and about 50 watts/channel.
The amplifiers we currently make here at Emotiva range from 50 watts/channel to 650 watts/channel into 8 Ohms... up to about 1000 watts into 4 Ohms.

In discussions like this - test data ends up being not much better than anecdotal data.
I could easily find a specific example where a 100 watt amplifier, driven into hard clipping at a certain frequency, would burn out the tweeter in a certain speaker.
While a more powerful amplifier, operating cleanly with that same test signal, at a higher power level, would not.
However, since continuous sine waves aren't especially typical of music, it would prove very little - other than that the possibility exists.
(And, if it's simply a matter of boosting the average power level, without clipping, then the danger will always be to the driver handling the primary frequency of the test signal.)

The actual operation of various software limiters varies quite widely (and depends on how you set them).
Some will allow you to clip, or "soft clip"; others will absolutely prevent clipping, but will cheerfully allow you to turn music into a solid wall of full-amplitude sine waves.
However, since, statistically, with typical music, the average power level is usually around 10% of the peak power, raising the average power level significantly above that is going to increase the risk of overheating all the drivers in a speaker.
And, while tweeters often receive a relatively small percentage of the total power, they are also often only able to tolerate a very low average power level long-term.
(So, if your music has a lot of high frequency content, raising the average power level is going to be more likely to damage the tweeter than the other drivers, independent of any spectral shift due to the clipping itself.)
In the old days, various types of deliberate limiting were also commonly found in the "protection circuitry" of amplifiers - but most modern amplifiers avoid this because it tends to compromise sound quality unacceptably.

I welcome you to show, with data, how the actual measurements I posted do not encompass common conditions. Just saying they don't doesn't count.

Hmmm.....perhaps you need to check up on what a square wave actually is. I've already shown what clipped audio looks like, and already given you actual levels of clipping at which you start to get pseudo-square waves with continuous sine waves as input, but you can't get a square wave at all out of actual music audio, nor does clipped audio approximate the spectrum of a square wave. I've already shown proof of this.
But the claim of the myth is that if you changed to an amp that does not clip but provides adequate drive, you won't damage your tweeters. To do that you need a higher power amp with similar gain. Then, if you want to turn that amp up, you can. But for comparison, we have to establish common factors, so with gain held constant we can then compare the effects of clipping on output power. I've shown that in the initial graph where you can see without doubt that a higher power non-clipping amp provides more RMS power to the load. Always.
Agreed.
No, I don't have that data at all. What I have is a lot of assumption based on unconfirmed data collected anecdotally. Do you, as a speaker manufacturer, have actual test data that confirms anything?
What I'm seeing these days is amplifiers have leveled at somewhere between 80 and 120 wpc, which lands pretty much every amp within a 1.8dB range of power output. It's actually hard to buy an underpowered amp given today's typical speaker efficiency. I would think a speaker/amp manufacturer would recognize this. Before you go to the high end exceptions, note that in the above you're talking about "the sort of people who buy under-powered amplifiers".
PLEASE DO THAT! You may learn a few things rather quickly.
Absolutely NOT. PLEASE TRY IT!
Nor have I.

OMG. Would you PLEASE read my other posts and look at the graphs? What, exactly, do you think I've been doing and posting????

 

[castleofargh]

do we all at least agree that to blow up a membrane or melt a coil(2 very different issues!), we need power reaching the limits for the driver, so obviously it's directly dependent on the specific driver and the specific output of the signal?
or are we really talking about a driver with specs giving, let's say 125dB for 4seconds as max output(or whatever way they have to define a working limit). and claim it will blow up without other defect because we played clipped music at 80dB? because I could be wrong but that seems silly to me and I certainly would like some evidence or nice electrical simulation showing me why it would happen.

should we bring in drivers that aren't mostly resistive in behavior? just to add some fun to the conversation. is it alright if I use the same paranoia to argue that high amplitude ultrasounds hurt my drivers(and my ears). so much energy, such rapid changes in direction for the poor membranes. let's all sue High Res sellers. (too far?)

 

[analogsurviver]

You seem to insist on treating certain generalizations as facts - while discounting others disproportionately.

As a few other people have noted, you can't get a true square wave out of digital audio at all - due to band limiting.
However, in order to be potentially dangerous, you don't actually need an especially good approximation.
For example, many popular speakers have a crossover between 1 kHz and 3 kHz, and second order, and even third order high-pass filters, are actually quite common.
So, if I start with a 1.5 kHz tone, as a pure tone it will be handled by the midrange, but even the first harmonic present in a vague approximation of a square wave (the third harmonic - at 4.5 kHz), will fall squarely into the tweeter.
And, since it is also relatively common for tweeters that are used above 3 kHz, with a third order filter, to have rather low power handling capabilities, this can be significant.
And, yes, you do have to clip the signal "pretty hard" to generate any significant power in the harmonics...
Because of this, it probably is far more likely that a speaker will be damaged by the high average power level of a heavily clipped signal than because of its spectral content.

The general way I've heard the assertion is "people with low powered amplifiers, who turn them up until they clip, in an attempt to get them to play loudly, are more likely to blow tweeters than people with more powerful amplifiers".
The assertion I'm familiar with is NOT that people with more powerful amplifiers are less capable of blowing tweeters if they make bad decisions - just that they are statistically less likely to do so.
And, while that may not always, or even necessarily, be the case, most people in the industry agree that it often is.
Incidentally, most companies are not able to collect data about exactly why tweeters get blown (customers tend to avoid admitting that they drove their amplifier into hard clipping, because that would count as abuse, and might void their warranty).

The reality is that people routinely harbor the belief that "if they have a 100 watt amplifier and 200 watt speakers they don't have to worry about how loud they turn up the amp because it isn't powerful enough to hurt their speakers".
And this frequently ends up being proven wrong by the practical lesson of a blown driver.

I would also disagree with your assertion about amplifier power (unless you're simply suggesting that "most people have at least a reasonable amount of power these days - which I tend to agree with).
We still routinely see AVR and smaller amplifiers in the range between 20 watts/channel and about 50 watts/channel.
The amplifiers we currently make here at Emotiva range from 50 watts/channel to 650 watts/channel into 8 Ohms... up to about 1000 watts into 4 Ohms.

In discussions like this - test data ends up being not much better than anecdotal data.
I could easily find a specific example where a 100 watt amplifier, driven into hard clipping at a certain frequency, would burn out the tweeter in a certain speaker.
While a more powerful amplifier, operating cleanly with that same test signal, at a higher power level, would not.
However, since continuous sine waves aren't especially typical of music, it would prove very little - other than that the possibility exists.
(And, if it's simply a matter of boosting the average power level, without clipping, then the danger will always be to the driver handling the primary frequency of the test signal.)

The actual operation of various software limiters varies quite widely (and depends on how you set them).
Some will allow you to clip, or "soft clip"; others will absolutely prevent clipping, but will cheerfully allow you to turn music into a solid wall of full-amplitude sine waves.
However, since, statistically, with typical music, the average power level is usually around 10% of the peak power, raising the average power level significantly above that is going to increase the risk of overheating all the drivers in a speaker.
And, while tweeters often receive a relatively small percentage of the total power, they are also often only able to tolerate a very low average power level long-term.
(So, if your music has a lot of high frequency content, raising the average power level is going to be more likely to damage the tweeter than the other drivers, independent of any spectral shift due to the clipping itself.)
In the old days, various types of deliberate limiting were also commonly found in the "protection circuitry" of amplifiers - but most modern amplifiers avoid this because it tends to compromise sound quality unacceptably.

Guys... - and @pinnahertz in particular - have you EVER connected to the speaker output terminals of the power amplifier any real measurement setup , that can - actually - detect the clipping while playing music ? Like an oscilloscope and/or peak hold meter ?

If you did - or do - then you will have no other choice but to concur with the fact that at least some of the time most audio SPEAKER setups are driven into clipping.

After adjusting the listening level to the level that actually is below clipping point all of the time, most speaker system setups will simply play at insufficient loudnes ...

The cruel fact is hidden here : https://en.wikipedia.org/wiki/Decibel_watt Although no longer permitted to be used in SI measuring units system, it is no less relevant because of that - since it DOES give a real world perspective - because it expresses the power in direct proportion to hgow we perceive loudness from a dynamic driver ( vast majority ) speakers. .

If you punch in the numbers, you get that 50 W amp has ( rounded to reasonable extent ) 17dBW, 100 W power amp has 20dBW, 200W amp has 23 dBW and 400 W has 26dBW . And 1000 W amp has 30 dBW . So, the difference in attainable SPL from these amp ( provided that the speakers can tolerate that much power ) is only 13 dB ...

Now... imagine you are in an audio shop. Say that all the amps with the above respective power ratings have identical sound quality ( they don't, as much as some would like you lead to believe ... ). I have no idea of the exact price of say Emotiva amps - but instead of the actual price in $, some ratio(s) would be enough. Long story short - MOST people do not have the money to purchase the amps they would actually really need for clipping free reproduction of uncompressed recordings. That's why in studios compressors/limiters are used - as most of the people simply do not have the capability to play them back on speakers at home. And if anyone is naive enough that this compessing/limitting bussiness does not apply to classical music on most major labels, should take off their rosy sunglasses and see the truth for a change.

Yes, people like Telarc's recording of Ouverture 1812 - but uncompressed/unclipped reproduction of those cannons exceed 130 dB. Only a handful of highly efficient igh power rating proffessional speakers can play this back correctly. And no one would enjoy just a smidge below real cannon fire levels in living room.

Now, let's say we use a speaker system with sensitivity of 88dB/W/m - a reasonable, if slightly above the average sensitivity speakers. . That means we need 100 W amp for 108 dB SPL from the speaker at 1m in an anechoic chamber. Room with normal reverberation adds to this another 3dB - and another speaker from the stereo pair another 3dB to the total of 114 dB SPL at 1 m from the speakers. As most dynamic speakers are approximately point sources, their SPL output falls off by the SQUARE of the distance from the speakers - so, at only 2 metres from the speakers, that means only 1/4 of the attainable SPL output at 1 m distance ... That can be compensated with both amps and speakers that can supply the necessary SPL at the listening position, which is hardly ever closer than 2 metres ...

If you followed to here, one can imagine a real world scenario : somebody has heard at his friend (boss ? ) a truly outstanding reproduction on speakers. Forget cannons, uncompressed recording of Mahler's 2nd symphony is more than it takes even best TOTL audio systems to clip. But let's say the system in question has been indeed capable of - just, by carefully checked well in advance of the "demo" that it stays below audible distress - playing back that recording - say, from a CD.

The person who heard this demo was thrilled with enthusiasm; bought the said CD ASAP. But, that person does not have the speakers as efficient as those of the boss, and instead of active driven speakers of the boss ( where bass clipping of the amp, even if and when it occurs, can not possibly bleed trough harmonics to tweeter ... ) only has a mid tier speakers with say 85dB/W/m real ( not brochure...) sensitivity and a receiver of say 65 W/ch. And would like to hear the same majestic finale as heard in that other "just slightly better system"... requiring at least 114 dB CLEAN peaks SPL in the finale.

Now, please do the math ... and see for how much time the poor power amp section of the receiver would be required to perform way above any reasonable level.
And ask yourself if you would risk it with a vintage set of speakers with tweeters that are no longer in production and by now costlier than their weight in gold.

 

[colonelkernel8]

If you punch in the numbers, you get that 50 W amp has ( rounded to reasonable extent ) 17dBW, 100 W power amp has 20dBW, 200W amp has 23 dBW and 400 W has 26dBW . And 1000 W amp has 30 dBW . So, the difference in attainable SPL from these amp ( provided that the speakers can tolerate that much power ) is only 13 dB ...

There is literally no way this is true. This completely ignores gain and the dB/watt efficiency of the speaker.

 

[TheSonicTruth]

Then make your point more succinctly. Either way, I think you are ignoring the reality of where technology is heading. The IoT is already a reality.

Your choices may not reflect everyone else’s, so no need to denigrate people who choose to adopt new technology. How many people have converted from physical media to media servers due to ease of use?

I used to have to wait for the news to get a weather forecast - now I use a smartphone or computer
I used to have to call a restaurant to place a takeout order or make a reservation - now I use an app most of the time for accuracy.
Still flushing my own toilet at home, but who hasn’t seen an auto flush toilet in a public place or business?

Not denigrating anyone. I just see *certain applications* of technology as 'reinventing the wheel' so to speak. Look at the 2009 DTV transition: was that just a ploy to sell more TVs or what? We had a perfectly functional broadcast TV system for neary 70 years by that point!

 

[Zapp_Fan]

Not denigrating anyone. I just see *certain applications* of technology as 'reinventing the wheel' so to speak. Look at the 2009 DTV transition: was that just a ploy to sell more TVs or what? We had a perfectly functional broadcast TV system for neary 70 years by that point!

Not just TVs, (although I am sure the TV companies appreciated it,) the government's motivation was selling spectrum. The FCC was able to re-sell rights the 700Mhz analog spectrum to new customers after the transition, IIRC the rights went for billions.

 

[KeithEmo]

In general, physically "breaking" a tweeter is quite uncommon... I've heard claims that occasionally certain particular metal dome tweeters can be overdriven badly enough to actually cause the dome to buckle - but I've never seen it happen.
(Since they dent very easily if you touch or bump them, which you might not even notice happening, I'm always inclined to take those stories with a grain of salt.)
Usually, with domes or cones, the voice coil will overheat and either burn through, fall apart into separate coils of wire, or separate from the rest of the driver (all fatal).
With planar ribbon drivers and folded ribbon drivers, the voice coil itself is a flat strip of foil covering most of the surface of the membrane.
It is a relatively common failure mode on those for part of the membrane to overheat and scorch or melt if the voice coil is overloaded.
When that happens, the metal may come loose from the membrane, or the membrane itself may melt and buckle, or both.
(The yellow plastic used in many planar tweeters is Kapton, which can stand a lot of heat; if you overheat it thoroughly enough, it will usually actually burn or blister.)

Drivers that actually move a significant distance can also fail because the flexible wire connecting the moving parts to the non-moving parts fails.
While this CAN happen with tweeters, it's much more common with woofers.)

In general, all of this damage results from heat.
Some tweeters, especially those with ferrofluid, and planar ones with a lot of area, can tolerate a lot of power for quite some time.
For those, a massive overload can burn them out in a few seconds, but less extreme overloads may be tolerated for many minutes, with the temperature rising gradually.
As a very wide generalization, older tweeters tended to be more susceptible to burning out more quickly, but it varies widely between individual drivers.
Also, because the amount of content in typical music drops rapidly as you go up in frequency, the crossover point makes a major difference.
Tweeters that are crossed over at a higher frequency, and those with a higher-order crossover (sharper filter), which more effectively keeps low frequencies out of the tweeter, are much more difficult to overheat.
The design of the speaker also plays a major role in other ways.
For example, on some speakers, the tweeter is more efficient than the other drivers, so its level may be reduced in the crossover by a series resistor...
(if so, 1/2 or 2/3 of the power you think is going into the tweeter, may be simply dissipated by that resistor).

I should also point out that the damage that results from "blasting the amp until it clips" is often not directly related to the fact that it's clipped.

A commonly used, and widely accepted, approximation is that, with typical music, unclipped, the average power level is usually between 1/10 and 1/20 of the peak level.
So, for example, if you have a 100 watt amplifier, which can deliver 200 watts peak, and you turn it up until clipping just starts, the average power output is probably between 10 and 20 watts.
However, if you ignore the clipping, or simply don't notice it, you can easily double or triple the AVERAGE output level by simply continuing to turn up the Volume.
How this affects our PERCEPTION varies between individuals.
In general, more distorted music is perceived as louder...
However, our ears adapt to loud sounds by reducing their sensitivity...

In combination, it is not uncommon for someone who "is trying to make the music play really loud" to turn it up until it distorts...
Then, after their ears adapt to the new level, it again "doesn't seem very loud", so they continue to turn it up...
Since they're already gone past the point where someone else would be warned by the onset of clipping that "they're playing it too loud"...
They can easily continue to turn the Volume up until finally something fails.

With few exceptions, the major factor is how much power reaches the voice coil of a given driver, and the time it continues (or the duty cycle).

do we all at least agree that to blow up a membrane or melt a coil(2 very different issues!), we need power reaching the limits for the driver, so obviously it's directly dependent on the specific driver and the specific output of the signal?
or are we really talking about a driver with specs giving, let's say 125dB for 4seconds as max output(or whatever way they have to define a working limit). and claim it will blow up without other defect because we played clipped music at 80dB? because I could be wrong but that seems silly to me and I certainly would like some evidence or nice electrical simulation showing me why it would happen.

should we bring in drivers that aren't mostly resistive in behavior? just to add some fun to the conversation. is it alright if I use the same paranoia to argue that high amplitude ultrasounds hurt my drivers(and my ears). so much energy, such rapid changes in direction for the poor membranes. let's all sue High Res sellers. (too far?)

do we all at least agree that to blow up a membrane or melt a coil(2 very different issues!), we need power reaching the limits for the driver, so obviously it's directly dependent on the specific driver and the specific output of the signal?
or are we really talking about a driver with specs giving, let's say 125dB for 4seconds as max output(or whatever way they have to define a working limit). and claim it will blow up without other defect because we played clipped music at 80dB? because I could be wrong but that seems silly to me and I certainly would like some evidence or nice electrical simulation showing me why it would happen.

should we bring in drivers that aren't mostly resistive in behavior? just to add some fun to the conversation. is it alright if I use the same paranoia to argue that high amplitude ultrasounds hurt my drivers(and my ears). so much energy, such rapid changes in direction for the poor membranes. let's all sue High Res sellers. (too far?)

There is literally no way this is true.

 

[KeithEmo]

Errrr... yes it is.
The sensitivity of our hearing is logarithmic.

Doubling the power increases the output by 3 dB... which, to most people, sounds "a little bit louder".
In order to make something "seem to be twice as loud" you typically require about ten times as much power (actually delivered to the air).

Note that this does NOT include accounting for the way the sensitivity of our hearing decreases when our ears are exposed to very loud noises for a period of time.
That effect tends to make the perceived difference of increasing the power even less.

And, yes, all else being equal, a speaker with 95 dB efficiency, playing at 10 watts, will be about as loud as a speaker with 95 dB efficiency, playing at 100 watts.

There is literally no way this is true. This completely ignores gain and the dB/watt efficiency of the speaker.

 

[analogsurviver]

Errrr... yes it is.
The sensitivity of our hearing is logarithmic.

Doubling the power increases the output by 3 dB... which, to most people, sounds "a little bit louder".
In order to make something "seem to be twice as loud" you typically require about ten times as much power (actually delivered to the air).

Note that this does NOT include accounting for the way the sensitivity of our hearing decreases when our ears are exposed to very loud noises for a period of time.
That effect tends to make the perceived difference of increasing the power even less.

And, yes, all else being equal, a speaker with 95 dB efficiency, playing at 10 watts, will be about as loud as a speaker with 95 dB efficiency, playing at 100 watts.

Errata corrige ( sure it was only typo )
:
And, yes, all else being equal, a speaker with 95 dB efficiency, playing at 10 watts, will be about as loud as a speaker with 85 dB efficiency, playing at 100 watts.

 

[pinnahertz]

You seem to insist on treating certain generalizations as facts - while discounting others disproportionately.

I've shown real data. Nobody has shown any data at all that proves my assertions wrong, including yourself.

As a few other people have noted, you can't get a true square wave out of digital audio at all - due to band limiting.
However, in order to be potentially dangerous, you don't actually need an especially good approximation.
For example, many popular speakers have a crossover between 1 kHz and 3 kHz, and second order, and even third order high-pass filters, are actually quite common.
So, if I start with a 1.5 kHz tone, as a pure tone it will be handled by the midrange, but even the first harmonic present in a vague approximation of a square wave (the third harmonic - at 4.5 kHz), will fall squarely into the tweeter.

True, but you haven't stated the power level, in RMS, of that harmonic. That's the key. Secondly, you're not EVER getting a square wave into the system at 1kHz without it being a complete accident. You need to drop this square-wave nonsense, it's not working to your favor.

And, since it is also relatively common for tweeters that are used above 3 kHz, with a third order filter, to have rather low power handling capabilities, this can be significant.
And, yes, you do have to clip the signal "pretty hard" to generate any significant power in the harmonics...
Because of this, it probably is far more likely that a speaker will be damaged by the high average power level of a heavily clipped signal than because of its spectral content.

"Pretty hard" is not data. So, here's how it actually works in real life. The graph set below shows the RMS spectrum of a pop tune, fully loudness-war processed, driven into hard clipping in 2dB steps.
NOTE:
1. Where's the highest amount of energy? Below 1kHz. That's true of most music, but in particular, that of the type that is processed enough to stay above clipping longer than a few peaks worth.
2. Does the spectrum chance with clipping, and if so, how much? Answer: The spectrum does not change, except for ultrasonics that are made visible by the 15kHz mp3 filter.
3. If the amp clips at a voltage that corresponds to 100W, at what level are the "harmonics", inclusive of actual music content, above a 3kHz 3rd order crossover? Answer: the energy at 3kHz and up is down at least 15dB from the highs energy area, or just over 3W.

If anything you're saying were even slightly true, wouldn't we see it in graphs such as this? The data is going the opposite direction of your assertions, and you still offer no data to support them.

The general way I've heard the assertion is "people with low powered amplifiers, who turn them up until they clip, in an attempt to get them to play loudly, are more likely to blow tweeters than people with more powerful amplifiers".
The assertion I'm familiar with is NOT that people with more powerful amplifiers are less capable of blowing tweeters if they make bad decisions - just that they are statistically less likely to do so.
And, while that may not always, or even necessarily, be the case, most people in the industry agree that it often is.

So, now you're revising the myth? Please review your original post regarding this. Nothing has ever been said or implied that people with higher power amps make better operating decisions. And I know of no professional that would agree with that at all, and I am acquainted with just a few.

Incidentally, most companies are not able to collect data about exactly why tweeters get blown (customers tend to avoid admitting that they drove their amplifier into hard clipping, because that would count as abuse, and might void their warranty).

So, you don't take a tweeter or three and put them in the lab, set up an amp for clipping, and just see what smokes? You guys have more facility than anyone else to do this. I guess perpetuating the myth must serve your company better than busting it.

The reality is that people routinely harbor the belief that "if they have a 100 watt amplifier and 200 watt speakers they don't have to worry about how loud they turn up the amp because it isn't powerful enough to hurt their speakers".
And this frequently ends up being proven wrong by the practical lesson of a blown driver.

Proven wrong? How? Do you have proof or not? If not, then stop making unsupported claims. If so, post the proof.

I would also disagree with your assertion about amplifier power (unless you're simply suggesting that "most people have at least a reasonable amount of power these days - which I tend to agree with).
We still routinely see AVR and smaller amplifiers in the range between 20 watts/channel and about 50 watts/channel.

Please post the model number of one...just one... 5.1 AVR from any of the big AVR companies (Denon, Pioneer, Sony, Yamaha) that has a maximum of 20WPC. And if you do find one, you'll have found the exception. I stand by my claim, anyone is welcome to check.

The amplifiers we currently make here at Emotiva range from 50 watts/channel to 650 watts/channel into 8 Ohms... up to about 1000 watts into 4 Ohms.

You're not making a single 50wpc AVR, are you?

In discussions like this - test data ends up being not much better than anecdotal data.
I could easily find a specific example where a 100 watt amplifier, driven into hard clipping at a certain frequency, would burn out the tweeter in a certain speaker.
While a more powerful amplifier, operating cleanly with that same test signal, at a higher power level, would not.

IF that's so incredibly easy to do, then you need to do it ASAP.

However, since continuous sine waves aren't especially typical of music, it would prove very little - other than that the possibility exists.

Other than to illustrate the spectral change of a sine way caused by clipping, I've never cited sine waves. My graphs were all made with actual music, and a hit record at that.

The actual operation of various software limiters varies quite widely (and depends on how you set them).
Some will allow you to clip, or "soft clip"; others will absolutely prevent clipping, but will cheerfully allow you to turn music into a solid wall of full-amplitude sine waves.
However, since, statistically, with typical music, the average power level is usually around 10% of the peak power, raising the average power level significantly above that is going to increase the risk of overheating all the drivers in a speaker.

Why are you now bringing software limiters into this discussion? Nowhere have I mentioned or used a software limiter. Amplifiers are not software, or hardware limiters.

And, while tweeters often receive a relatively small percentage of the total power, they are also often only able to tolerate a very low average power level long-term.
(So, if your music has a lot of high frequency content, raising the average power level is going to be more likely to damage the tweeter than the other drivers, independent of any spectral shift due to the clipping itself.)

Reputable driver manufactures state power handling as a function of frequency, power and time. My analysis includes all of those parameters.

In the old days, various types of deliberate limiting were also commonly found in the "protection circuitry" of amplifiers - but most modern amplifiers avoid this because it tends to compromise sound quality unacceptably.

Really? Ever looked at current product from QSC? Crown? Any current professional amp? Yeah, didn't think so. Protection is not only built in, but configurable as to what level it operates, how it operates, etc. All of those and many more have on-board DSP that does..well, a lot. Built in. And very effective. And sounds better than clipping!

 

[pinnahertz]

Guys... - and @pinnahertz in particular - have you EVER connected to the speaker output terminals of the power amplifier any real measurement setup , that can - actually - detect the clipping while playing music ? Like an oscilloscope and/or peak hold meter ?

Yes, but it's been a while, probably at least 48 hours ago.

If you did - or do - then you will have no other choice but to concur with the fact that at least some of the time most audio SPEAKER setups are driven into clipping.

Let me as you the same question, then. Have YOU ever scoped an amp driving a speaker? I didn't think so, your you'd know the above is nonsense.

After adjusting the listening level to the level that actually is below clipping point all of the time, most speaker system setups will simply play at insufficient loudnes ...

Well, these days, with AVRs hovering around 100wpc, and an industry-wide target reference SPL at the LP of 80dB SPL with 20dB of headroom, most decent speakers are designed so that at the typical listening distance they can come within 3dB of that reference level, and most hit it at all but extreme bass frequencies.

The cruel fact is hidden here : https://en.wikipedia.org/wiki/Decibel_watt Although no longer permitted to be used in SI measuring units system, it is no less relevant because of that - since it DOES give a real world perspective - because it expresses the power in direct proportion to hgow we perceive loudness from a dynamic driver ( vast majority ) speakers. .

If you punch in the numbers, you get that 50 W amp has ( rounded to reasonable extent ) 17dBW, 100 W power amp has 20dBW, 200W amp has 23 dBW and 400 W has 26dBW . And 1000 W amp has 30 dBW . So, the difference in attainable SPL from these amp ( provided that the speakers can tolerate that much power ) is only 13 dB ...

Ok, let me punch in some real numbers for you. In fact, you can do it yourself here: http://myhometheater.homestead.com/splcalculator.html
Speaker sensitivity of 90dB/W/m, LP at 8', amp at 100W, two speakers...DING! you hit industry reference for maximum peak at 0dBFS. How hard was that?? There are many 90dB speakers, some above that, a few below by a few dB. It's not hard to make it loud enough without clipping your amp.

Now... imagine you are in an audio shop. Say that all the amps with the above respective power ratings have identical sound quality ( they don't, as much as some would like you lead to believe ... ). I have no idea of the exact price of say Emotiva amps - but instead of the actual price in $, some ratio(s) would be enough. Long story short - MOST people do not have the money to purchase the amps they would actually really need for clipping free reproduction of uncompressed recordings.

First of all, nobody in their sane mind would tollerate the nonsens in an "audio shop". Horrible places. I stay away. Second, your coupling of price per watt makes no sense at all. Keiths company does pretty well with the value of a watt. But there are others the do even better. It's absolutely not difficult at all for anyone to get what they need for clip-free sound. I've not yet heard such a wild and meaningless assertion, though, so kudos on that.

That's why in studios compressors/limiters are used - as most of the people simply do not have the capability to play them back on speakers at home.

As a practitioner in this venue, I object to your completely wrong statement above. That's NOT why compressors and limiter are used. You have no idea of what you are speaking!

And if anyone is naive enough that this compessing/limitting bussiness does not apply to classical music on most major labels, should take off their rosy sunglasses and see the truth for a change.

Lets not go down this road. There are examples of processed classical music, but the majority is minimally processed, or not at all. You'll find most of the processed and limited classical music on vinyl, the processor was a Fairchild limiter...known industry wide.

Yes, people like Telarc's recording of Ouverture 1812 - but uncompressed/unclipped reproduction of those cannons exceed 130 dB. Only a handful of highly efficient igh power rating proffessional speakers can play this back correctly. And no one would enjoy just a smidge below real cannon fire levels in living room.

Wrong...again. You cannot state the SPL of any sound source without including a distance to the source. A nuclear explosion is inaudible if you're on the other side of the world, but the highest possible SPL on earth of you're down the street.

Now, let's say we use a speaker system with sensitivity of 88dB/W/m - a reasonable, if slightly above the average sensitivity speakers. . That means we need 100 W amp for 108 dB SPL from the speaker at 1m in an anechoic chamber. Room with normal reverberation adds to this another 3dB - and another speaker from the stereo pair another 3dB to the total of 114 dB SPL at 1 m from the speakers. As most dynamic speakers are approximately point sources, their SPL output falls off by the SQUARE of the distance from the speakers - so, at only 2 metres from the speakers, that means only 1/4 of the attainable SPL output at 1 m distance ... That can be compensated with both amps and speakers that can supply the necessary SPL at the listening position, which is hardly ever closer than 2 metres ...

Except for the anechoic chamber, that's fairly reasonable.

If you followed to here, one can imagine a real world scenario : somebody has heard at his friend (boss ? ) a truly outstanding reproduction on speakers. Forget cannons, uncompressed recording of Mahler's 2nd symphony is more than it takes even best TOTL audio systems to clip. But let's say the system in question has been indeed capable of - just, by carefully checked well in advance of the "demo" that it stays below audible distress - playing back that recording - say, from a CD.

The person who heard this demo was thrilled with enthusiasm; bought the said CD ASAP. But, that person does not have the speakers as efficient as those of the boss, and instead of active driven speakers of the boss ( where bass clipping of the amp, even if and when it occurs, can not possibly bleed trough harmonics to tweeter ... ) only has a mid tier speakers with say 85dB/W/m real ( not brochure...) sensitivity and a receiver of say 65 W/ch. And would like to hear the same majestic finale as heard in that other "just slightly better system"... requiring at least 114 dB CLEAN peaks SPL in the finale.

Now, please do the math ... and see for how much time the poor power amp section of the receiver would be required to perform way above any reasonable level.
And ask yourself if you would risk it with a vintage set of speakers with tweeters that are no longer in production and by now costlier than their weight in gold.

I'll have to address your peak/average SPL confusion at a later time, but it will throw you off.

I've already addressed the core of your last issue in a previous post. You can always cherry-pick a situation that underscores your statement. But how real is it? Not very.

 

[analogsurviver]

Yes, but it's been a while, probably at least 48 hours ago.
Let me as you the same question, then. Have YOU ever scoped an amp driving a speaker? I didn't think so, your you'd know the above is nonsense.

Well, these days, with AVRs hovering around 100wpc, and an industry-wide target reference SPL at the LP of 80dB SPL with 20dB of headroom, most decent speakers are designed so that at the typical listening distance they can come within 3dB of that reference level, and most hit it at all but extreme bass frequencies.

Ok, let me punch in some real numbers for you. In fact, you can do it yourself here: http://myhometheater.homestead.com/splcalculator.html
Speaker sensitivity of 90dB/W/m, LP at 8', amp at 100W, two speakers...DING! you hit industry reference for maximum peak at 0dBFS. How hard was that?? There are many 90dB speakers, some above that, a few below by a few dB. It's not hard to make it loud enough without clipping your amp.
First of all, nobody in their sane mind would tollerate the nonsens in an "audio shop". Horrible places. I stay away. Second, your coupling of price per watt makes no sense at all. Keiths company does pretty well with the value of a watt. But there are others the do even better. It's absolutely not difficult at all for anyone to get what they need for clip-free sound. I've not yet heard such a wild and meaningless assertion, though, so kudos on that.
As a practitioner in this venue, I object to your completely wrong statement above. That's NOT why compressors and limiter are used. You have no idea of what you are speaking!
Lets not go down this road. There are examples of processed classical music, but the majority is minimally processed, or not at all. You'll find most of the processed and limited classical music on vinyl, the processor was a Fairchild limiter...known industry wide.
Wrong...again. You cannot state the SPL of any sound source without including a distance to the source. A nuclear explosion is inaudible if you're on the other side of the world, but the highest possible SPL on earth of you're down the street.
Except for the anechoic chamber, that's fairly reasonable.

I'll have to address your peak/average SPL confusion at a later time, but it will throw you off.

I've already addressed the core of your last issue in a previous post. You can always cherry-pick a situation that underscores your statement. But how real is it? Not very.

1. Good for you.

2. Many times - but, most recently, for electrostatic amps and transformers. As ESLs are voltage and not power sensitive devices, different math is involved - but scope remains the same, only probes have to withstand the KVs required.

3. Well, the figures you posted are good enough for typical commercial compressed/limited releases. "Only" some 10-20 dB short of the real thing.

4. Where does one go to purchase audio ? Or, to be more precise, to listen to some gear that nowadays people then go shamelessly afterwards to order online, for a small difference in price - if not audio shop ?

5. Play some recordings from Telarc and Reference Recordings - which have not been squashed iinto something palatable on equipment of your description. And see if your whatever attached to the amp output does not show clipping ...
But definitely do not try that with my demo pieces - at least if you want to retain any credibility that modern day amp/speakers combos do not clip - at least sometimes.

For this reason, I absolutely hate any Magico or Avalon speaker - no way there is an amp powerful enough to coax anything approaching live dynamic range - even if they were actually capable of taking enough power.

6. You can spin why and how compressors and limiters are used any way you like - part of the reason is as I have stated. Remember, the 1812 record you like exists in 3 versions because of this - if no one but greatest fanatics can use and enjoy it, it is not a good commercial product. So, a moderated version had to be created.

7. Yes, VERY quickly into - let's call it "turntable research" - I figured out that all kinds of things better left unnamed have been done to records - for the precisely the samee reasons as above . I know analogue record is limited, but those limitations are nowhere as severe as in some commercial releases.

8. SPL vs distance is debatable ... that's why line source speakers are used for big rooms, as their SPL falls not by a distance squared ( as in point source ), but linearly - and so on and so forth.
A bomb on the other part of the world is - strictly speaking - not inaudible; only has to be big enough. The Tzar Bomb shockwave went 4 times around the globe ... and at least some effects of that were audible long, long away from the epicentre.

 

[71 dB]

The reality is that people routinely harbor the belief that "if they have a 100 watt amplifier and 200 watt speakers they don't have to worry about how loud they turn up the amp because it isn't powerful enough to hurt their speakers".
And this frequently ends up being proven wrong by the practical lesson of a blown driver.

The problem is perhaps that people don't realize the 200 W speaker rating is for peak power, which means the program power handling is maybe only 100 W and continuous power handling only 50 W. A clipping 100 W amp gives maybe 150 W which exceeds program power not to mention continuous power!

 

[analogsurviver]

Something for the Doubting Thomases :

https://www.hifiengine.com/manual_library/technics/sh-9020.shtml

https://kenrockwell.com/audio/technics/sh-9020.htm

The thing requires only A SINGLE HALFWAVE UP TO 10kHz
to display - correctly to within specs etc given in the link above - peak hold ; that peak is then held to within fraction of a dB - for hours ...

FAR more accurate than any oscilloscope could ever be; humans can see approx 40-60 frames per second as separate, non continuos image - at best. No way a human being can see on the scope a SINGLE halfwave of 10 kHz - clipped or unclipped - during normal music reproduction.

And it is THE reason why it is the most sought after component from the Technics' Proffessional Series; no serious analogue recordist can afford to be without one. And if you can't figure out why it is indispensable with digital recording too - it is your loss.

As you can see, it can monitor - with the very same accuracy - also output from power amp, up to 1000 W. Something EVERY person serious about quality reproduction should have - at least once in a lifetime - see with very own eyes, in very own system.

The only comparable unit was from Aurex ( Toshiba ) . So rare that I never saw it anywhere else than on Japan Audio Heritage site http://audio-heritage.jp/AUREX/etc/pm-55.html

 

[bigshot]