Klipsch's Law and Corollaries

[Chris A]

Recently, I found that once again there is a pernicious and persistent desire to rewrite Hofman's Iron Law...

 

"It is not possible to combine high efficiency with compact enclosure size and adequate low frequency response: only two of the three parameters can be optimized when designing a loudspeaker system."

 

PWK found (empirically) that:

 

higher efficiency loudspeakers = lower distortion loudspeakers

 

Put the two observations together and you get what I am calling Klipsch's Law:

 

"It is not possible to achieve low-distortion output with a compact loudspeaker enclosure size and also have adequate low-frequency response."

 

Adding PWK's empirical observation that horn-loaded drivers have ~25 dB less distortion than those same drivers used in a direct-radiating enclosure, you get what I call Klipsch's First Corollary:

 

"Horn-loaded drivers will always have lower distortion output than if used in a direct-radiator enclosure."

 

Turning this back around using Hofman's Iron Law yet again, you get Klipsch's Second Corollary:

 

"All other factors being equal, the larger the horn-loaded low frequency speaker enclosure, the lower its low-frequency distortion."

 

 

Adding the observation that loudspeaker distortion is a function of output SPL, then you get Klipsch's Third Corollary (actually, a permutation of the First Corollary):

 

"All other factors being equal, drivers used in a direct-radiating enclosure will have much less dynamic range for a given output distortion level than the same drivers used in a horn-loaded enclosure."

 

 

You want small, aesthetically pleasing loudspeakers? You trade away low distortion and dynamic range. Any time that you see a high-priced loudspeaker with direct-radiating drivers (e.g., Wilson, etc.) - think "high distortion" and "limited dynamic range" vs. a fully horn-loaded speaker--even those that use much lower cost drivers.

 

I believe that PWK started his company on this principle.

 

Chris 

[Guest " "]

I think we can generalize this further, which will illustrate, applications where these"law's" don't make any sense....take the diaphragm in a pair of headphone's....light weight...small...wide dynamic range...efficient...high spl (relative to the listening position)...regardless of the manufacture of the headphones.

compare headphones to horns and you would get the same mis interpretation of the laws as you would comparing horns to direct radiators.

you can take this furthur by comparing output transformers that do use helicoil windings vs those that don't.....the trannies with helicoil windings are smaller, lighter, more efficient, wider dynamic range, cooler operating, and the rest of the associated invertible characteristics that exists in normally wound trannies. you kind of have to establish fundament assumptions......you can't really compare across different technologies with out some constants.

a better analysis would be to compare apples to apples and oranges to oranges....or horns to horns or direct radiators to direct radiators...or headphones to headphones

[Chris A]

Law of Unhappy Peculiarities (p. 42, An Introduction to General Systems Thinking, Weinberg, G., 2001, Dorset House):

 

Any general law is bound to have at least two exceptions; OR If you never say anything wrong, you never say anything.

 

Law of Conservation of Laws (p. 41):

 

When the facts contradict the law, reject the facts or change the definitions, but never throw away the law...

 

I think that I'll stand by what is written...I think most people will find it useful...(maybe not everyone...)

 

[DizRotus]

I think that I'll stand by what is written...I think most people will find it useful...(maybe not everyone...)

As well you should. I find it interesting as well as useful.

It's counterintuitive. Most people incorrectly assume that the big Klipschorns require more power than my small BBC LS3/5As, when, in fact, the opposite is true.

The LS3/5As are excellent speakers for their intended use as mobile monitors. A premium was placed on a compact foot print. Nonetheless, they require a prodigious amount of power to prouduce limited bass and limited dynamic range and increased distortion, as compared to Khorns, but Khorns would be miserable as mobile monitors.

[BEC]

I think I heard this law stated a bit differently. I don't know where this came from.

1. You can have small speakers.

2. You can have high efficiency speakers.

3. You can have good low frequency response.

Pick any two of the above

[Chris A]

I like that one...

[Marvel]

but Khorns would be miserable as mobile monitors.

Or used in a HUGE remote truck.

Most people incorrectly assume that the big Klipschorns require more power than my small BBC LS3/5As, when, in fact, the opposite is true.

Or people think that the speakers have to be loud just because they are big. They don't understand dynamic range...

Bruce

[Chris A]

Or people think that the speakers have to be loud just because they are big. They don't understand dynamic range...

Bruce

I think that aspect of high quality horn-loaded speakers is not talked about very much: their low volume performance is very under-appreciated. The bass is not "in your face" - it's much more life-like than other speakers (ref. Heyser's Khorn review) - and in some ways reminds me of planar loudspeakers (electrostatics, dynamic planars) at low volumes - but horn-loaded speakers' dynamic range quickly distinguishes them from planars.

For instance, playing Holst's "Mars, the Bringer of War" or perhaps Ravel's Bolero (which I really don't play very often) it is amazing to me the great dynamic range that my horns have. I have to play those pieces when nothing else is going on in the house since they will eventually halt conversation anywhere in the house as the volume crescendos from quiet beginning to its ƒƒƒƒ climax.

[H]

Chris

[garyrc]

I think I heard this law stated a bit differently. I don't know where this came from.

1. You can have small speakers.

2. You can have high efficiency speakers.

3. You can have good low frequency response.

Pick any two of the above

So, it is possible to use subwoofers to achieve # 3, while sticking with # 2 and, possibly even # 1, for one's main speakers. The trouble is, I've never heard a subwoofer that didn't sound at least a little distorted, compared to the clean sound of a La Scala (or a Klipschorn properly sealed into an adequate corner). That's why I cut in my sub at 40 Hz, rather than higher. I have never heard a horn subwoofer, but they exist, and I'll bet they are better.

[garyrc]

For instance, playing Holst's "Mars, the Bringer of War" or perhaps Ravel's Bolero (which I really don't play very often) it is amazing to me the great dynamic range that my horns have. I have to play those pieces when nothing else is going on in the house since they will eventually halt conversation anywhere in the house as the volume crescendos from quiet beginning to its ƒƒƒƒ climax.

Chris

Yes, let's hear it for ffff. Stravinsky marked the end of the Firebird
suite that way, and that's how we play it over our Klipschorns ... only a
horn could do it so well, IMO.. The conductor of an orchestra I was in
re-marked the end of Pictures at an Exposition (The Great Gate of Kiev) ffff, and, in regard to the Great Gong part, said "Use a hard beater, and play it sffffz, if you can. A friend in the audience said "You guys stripped the paint off the walls."

[Coytee]

Or people think that the speakers have to be loud just because they are big.

Interestingly, there seem to be one or two people on this very forum who also have that opinion....

[DrWho]

Put the two observations together and you get what I am calling Klipsch's Law:

"It is not possible to achieve low-distortion output with a compact loudspeaker enclosure size and also have adequate low-frequency response."

I'm actually going to disagree with the Klipsch's law you derived here as there are plenty of examples of lower distortion than the Jubilee acheived with smaller enclosures (albeit a lot more power).

Adding PWK's empirical observation that horn-loaded drivers have ~25 dB less distortion than those same drivers used in a direct-radiating enclosure, you get what I call Klipsch's First Corollary:

"Horn-loaded drivers will always have lower distortion output than if used in a direct-radiator enclosure."

When the drivers are of the same technology then I would totally agree here. However, I would point out that the ideal horn loaded driver will not be the ideal direct radiator for the same application.

Any time that you see a high-priced loudspeaker with direct-radiating drivers (e.g., Wilson, etc.) - think "high distortion" and "limited dynamic range" vs. a fully horn-loaded speaker--even those that use much lower cost drivers.

One of the advantages to the Wilson is the distortion products for each driver are vastly reduced due to the limited bandwidth for each driver. I think the biggest problem then becomes the extra xover artifacts. In other words, reducing bandwidth will reduce distortion so it's not quite apples to apples.

Anyways, some interesting topics to think about. I'm kinda hoping my comments spur on some discussion as I find this topic very interesting.

[russ69]

No. Just like any device there are engineering trade offs. In the case of high efficiency designs, there are many trades, including frequency response accuracy and extension. I'm NOT saying that the Klipsch are somehow inferior due to the design. I'm just saying the speaker has trade offs, just like any other design.

"...Horn-loaded drivers will always have lower distortion output than if used in a direct-radiator enclosure..."

"...the larger the horn-loaded low frequency speaker enclosure, the lower its low-frequency distortion..."

These two assumptions are a bit too much. Servo controlled direct radiator sub woofers for example often are much lower in distortion and low frequency response than horn systems tuned for a specific frequency, although their efficiency is poor.

[Axz Hout]

B

[dtel]

Or people think that the speakers have to be loud just because they are big.

Interestingly, there seem to be one or two people on this very forum who also have that opinion....

I would bet money on that, a safe bet around here.

[Chris A]

I'm actually going to disagree with the Klipsch's law you derived here as there are plenty of examples of lower distortion than the Jubilee achieved with smaller enclosures (albeit a lot more power).

"In God we Trust...everyone else bring data..."

Not that I'm disagreeing with your statement...I simply don't have the data that you refer to--to say the PWK was wrong in his original observation of "the higher the efficiency, the lower the distortion", who you are clearly stating was wrong with your statement.

Do you have a URL to that data?

Chris

[dtel]

Or people think that the speakers have to be loud just because they are big. They don't understand dynamic range...

Bruce

Your exactly right Marvel, when someone notices them in our room one of the first comment is about volume.

The other side of that is besides dynamic range is efficiency, a speaker not even using but a few percent of what is already a very high efficiency rating already has got to have only a small percent of designed distortion, not even considering extreme headroom.

The funny part is with everyone who has seen the MWM's in the room not one person realized the bass bins were even speakers, they walk up to the 402 horns and comment about the size. After a couple of minutes I say these are the bass bins for the horns, they usually look in them and say where's the speakers.

. After somewhat explaining the inside shape they usually step back and look at the whole thing with that amazed/dumbfounded look when they realize the whole thing is a speaker.

I have to say it is funny, we are use to them being here but it really is a shock to others. Most women have that "have you lost your mind" look, most men just smile and can't stop staring at them, it really is funny.

[Coytee]

they usually step back and look at the whole thing with that amazed/dumbfounded look

it really is funny

Indeed, I can just see it happening there. I love it

[Y]

[garyrc]

... they usually step back and look at the whole thing with that amazed/dumbfounded look when they realize the whole thing is a speaker.

Most women have that "have you lost your mind" look, most men just smile and can't stop staring at them, it really is funny.

• Several decades ago, before the advent of reasonable quality satelites and subwoofers, both women and men were more tolerant of large speakers. The Bozak Concert Grand, the Klipschorn, the JBL Paragon, and the EV Patrician, were elegant looking (and sounding) pieces of living room decor. I saw no difference in acceptance by women and men. One woman used to sit on one of my big JBLs to "feel the music."
• This all changed when people starting accepting the doctrine that a speaker didn't have to be big to be good as a fact instead of a factoid.

[dtel]

I fell for that sub satellites [bs], it did make sense at the time. What I didn't consider was no matter how you do it it still sounds like a small speaker for the mids and highs.

I didn't fall for it completely I used the Klipsch SB 3, SC1 and SS1 and they were not really tiny. But after reading here a couple of years I finally got a grip, or lost it however you look at it ?

Of all the people who heard them one relative really appreciated it way more than anyone else, so we gave them to him for Christmas. He was happy and I was even more happy because I replaced them with forte ll's. That was the start of a upward slip or downward depending again on how you look at it. [Y]