Richard C. Heyser's Klipschorn review

[PrestonTom]

Geez,

You guys are bickering about details about time alignment and the interesting stuff is about bass accuracy. The thing that always struck me about this article is that he discusses accuracy (i.e., a door car slamming sounds like a door car slamming ...). The guy has had an epiphany that what he thought was "proper" bass was incorrect and the K-horns were in fact not deficient, but they were in fact accurate. This is the real news. How often do folks use words like warm & slam, and whatever, when they should be talking about accuracy. This is big issue guys, forget about the other stuff.

Good Luck,

-Tom

[DrWho]

That's a great point Tom. In fact, the Khorn has been one of the most annoying speakers I've come across because of that very fact...(and the Heyser article got me thinking about it)

[mas]

Dr. Who ..

You should find it interesting that R. Heyser states the KH bass bin .. needs 8ms alignment ..

didn't we always talk 7 ms...?? in the Ball Park, baby ..[]

The real trick would have been dialing it in by ear. []

By ear??

...Bunch of freakin' Luddites!

I did it with my RS SPL meter and the fancy deluxe model RTA and the SRD test CD! (because 31 channels of SPL meter are more accurate than just 1)

Now, if I can just find a high enough quality EQ...I'll be set...

[][*-)]

Note: It is my nightmare that someone is sitting there now, after reading the above, and saying to themselves, "Hey, I have some of that stuff! I can do it too!"

Why am I sufficiently dismayed enugh to come back and add the addendum that the above common procedure is absolutely and utterly worthless for this purpose!? I shouldn't have to...

[Spongeworthy]

That's a great point Tom. In fact, the Khorn has been one of the most annoying speakers I've come across because of that very fact...(and the Heyser article got me thinking about it)

Just curious and not being critical, but you are very clear in the Klipsch speakers that you don't like. What do you like?

[mas]

Geez... they should be talking about accuracy. This is big issue guys, forget about the other stuff.

Tom, the very inaccuracy that concerned Heyser (and was fundamental to his thinking) was precisely "that other stuff", namely accurately reproducing the signal (and in particular the transitions between drivers) within the time domain.

So one wonders what "other stuff" it is that we should forget.

Its pretty bad when you have first order room reflections arriving BEFORE individual direct signals! And if one is familiar with the concept behind the establishment of the ISD in a room, having direct signals violate this concept is a bit laughable.

Not aligning the various signals in time renders the speaker "a mess". But once it is properly aligned, many issues easily resolve themselves.

Can it be done? Sure! Is it worth it? Absolutely. Would I pay big bucks for another fancy passive crossover that fails to solve this issue, regardless of how fancy the caps are? Heck no!

This problem was objectively identified and detailed in 1986. Yet over 20 years after the fact, and among those who claim to be aficionados of the units, we still are not addressing such a fundamental problem.

What in hell does it take, folks?

The real irony is that none of this should be new or a surprise to anyone.

...Likewise for the Cornwall, LaScala and the Jubilee.

[]

Don Davis is right!

If bad sound were fatal, audio would be a leading cause of death!"

[pauln]

I

suppose I will catch the wrath of the time domain folks about this. First, I

don't understand about the problems and solutions time alignment addresses with

the transition between drivers, and issues with frequencies fairly close

together. There is much I don't understand about it. It appears that some of

these problems are specific to the electronic aspect of the signal, and

somewhat to the physical nature of the sound waves close to the speaker

elements. I can grant without demonstration that these aspects exist and may be

mitigated with time alignment.

But,

from the perspective of the listener, especially regarding the gross alignment

of the low bass with the rest of the spectrum; in my little flat Earth way of

thinking about it I wonder if time alignment correction is a solution without a

problem. I don't see how time alignment of electronic signals and driver

response can ensure that the ear will hear those signals as time aligned unless

one deliberately advances the low frequencies well ahead of the higher ones to

such a degree that the resultant sound would no longer resemble the natural

sound of live music.

We

don't hear any sounds instantaneously. The transmission from eardrum to basilar

membrane in the organ of corti is first mechanical through the three ossicles,

then hydraulic from the round window to the hair cells, then mechanical shear

on the hair cells, then chemical ion release from the hair cells to the

neurons. Once the neurons are depolarized the signal is passed through four

independent channels of preprocessing in progressive levels of auditory nuclei

before reaching the auditory cortex. So in essence, it takes time to hear sound

well after it reaches the listener's ears.

We

don't hear the onset of all frequencies simultaneously. It takes a minimum

number of completed cycles of a tone to be defined enough for processing and

perception of it. Lower frequency tones take longer to hear when they begin. In

the time it takes a 40Hz wave to complete just one cycle a 400Hz wave beginning

at the same time will complete 10 cycles, a 4000Hz wave 100 cycles. So in

essence, we naturally hear different frequencies after variable delays, the

lower the slower.

How

many cycles of a bass note need to be completed before you hear it? I don't

know what the minimum number of cycles is but it has to be a few... If it takes

5 cycles to hear a 50Hz note thats 100ms. Same with 3 cycles of 30Hz. 3 cycles

of 60 Hz would be 1/20s or 50ms. These are low guesses at the cycle

counts for perception, but aren't these processing to perception delays all

much longer than the time alignment delays between the higher horn drivers and

bass horn driver? The 8ms figure mentioned to correct the bass horn delay -

that's the time for a 125Hz note to execute only a single cycle. Even in a

perfectly aligned system you would naturally hear the higher frequencies well

before the bass cycles had much of a start on defining the waveform. The lowest

ones would be yet incomplete in finishing their first cycle well after you had

heard the higher tones..

Is it an assumption of time alignment that the

listener should be hearing the onset of all frequency pitches at the same time?

Wouldn't this require advancing the lowest notes way out ahead of the higher

ones? Or is it an assumption of time alignment that the drivers should be

phased so that the onset of all frequency pitches produce an aligned sound wave

front? Seems the lower frequency notes naturally resolve themselves in the

listener's ear/mind so much more slowly than the higher tones that the aligned

sound wave front would not be a sufficient correction to be noticed.

[mas]

I

suppose I will catch the wrath of the time domain folks about this. First, I

don't understand about the problems and solutions time alignment addresses with

the transition between drivers, and issues with frequencies fairly close

together. There is much I don't understand about it. It appears that some of

these problems are specific to the electronic aspect of the signal, and

somewhat to the physical nature of the sound waves close to the speaker

elements. I can grant without demonstration that these aspects exist and may be

mitigated with time alignment.

But,

from the perspective of the listener, especially regarding the gross alignment

of the low bass with the rest of the spectrum; in my little flat Earth way of

thinking about it I wonder if time alignment correction is a solution without a

problem. I don't see how time alignment of electronic signals and driver

response can ensure that the ear will hear those signals as time aligned unless

one deliberately advances the low frequencies well ahead of the higher ones to

such a degree that the resultant sound would no longer resemble the natural

sound of live music.

We

don't hear any sounds instantaneously. The transmission from eardrum to basilar

membrane in the organ of corti is first mechanical through the three ossicles,

then hydraulic from the round window to the hair cells, then mechanical shear

on the hair cells, then chemical ion release from the hair cells to the

neurons. Once the neurons are depolarized the signal is passed through four

independent channels of preprocessing in progressive levels of auditory nuclei

before reaching the auditory cortex. So in essence, it takes time to hear sound

well after it reaches the listener's ears.

We

don't hear the onset of all frequencies simultaneously. It takes a minimum

number of completed cycles of a tone to be defined enough for processing and

perception of it. Lower frequency tones take longer to hear when they begin. In

the time it takes a 40Hz wave to complete just one cycle a 400Hz wave beginning

at the same time will complete 10 cycles, a 4000Hz wave 100 cycles. So in

essence, we naturally hear different frequencies after variable delays, the

lower the slower.

How

many cycles of a bass note need to be completed before you hear it? I don't

know what the minimum number of cycles is but it has to be a few... If it takes

5 cycles to hear a 50Hz note thats 100ms. Same with 3 cycles of 30Hz. 3 cycles

of 60 Hz would be 1/20s or 50ms. These are low guesses at the cycle

counts for perception, but aren't these processing to perception delays all

much longer than the time alignment delays between the higher horn drivers and

bass horn driver? The 8ms figure mentioned to correct the bass horn delay -

that's the time for a 125Hz note to execute only a single cycle. Even in a

perfectly aligned system you would naturally hear the higher frequencies well

before the bass cycles had much of a start on defining the waveform. The lowest

ones would be yet incomplete in finishing their first cycle well after you had

heard the higher tones..

Is it an assumption of time alignment that the

listener should be hearing the onset of all frequency pitches at the same time?

Wouldn't this require advancing the lowest notes way out ahead of the higher

ones? Or is it an assumption of time alignment that the drivers should be

phased so that the onset of all frequency pitches produce an aligned sound wave

front? Seems the lower frequency notes naturally resolve themselves in the

listener's ear/mind so much more slowly than the higher tones that the aligned

sound wave front would not be a sufficient correction to be noticed.

No.

Try listening to headphones. How many cycles are necessary?

Assuming an ear canal length of 1 inch, you wouldn't hear anything below ~13,500 Hz. That must excite the headphone folks.

And various wavelengths/frequencies do not have different velocities!

And a "solution without a problem"? Start by reading about the Henry precedence effect and the subset of corollaries ofter referred to as the Haas effect. I don't have any problem debating ideas based upon fact, but isn't it time that you read just a little about modern applied acoustical theory?

I would suggest starting with the Davis and Patronis Sound System Engineering, 3rd Ed. And you can ignore ALL of the math and have no problem understanding the basic principles. Check the library, and if they do not have it, the interlibray loan program.

I don't mean to be rude, but this is akin to my questioning the biologists who claim to see little invisible bugs in water through something called, I think, a tiny-scope, and those silly physicists who claim that stuff is made up of weird little things called 'adams'. What bozos!

[pauln]

Not sure to which question "No" is in response.

Headphones...The headphone does present the aligned wave front, being single element; but I don't think that changes the natural perception delay for hearing the lower frequencies; still have to have some cycles to do it, and in that time the high frequencies have already been heard.

I don't follow why nothing below 13.5KHz... the cycles of low frequency needed for perception don't have to occupy a line of sight space, just need the pulse times to cycle the eardrum of the listener.

Precedence and Haas I have read about. I don't think they address my questions.

The only review I found of the book you recommended is not complimentary, not familiar with this editor [*-)] http://www.en-genius.net/site/zones/endZONE/columns__book_reviews/book0212

[mas]

Not sure to which question "No" is in response.

Headphones...The headphone does present the aligned wave front, being single element; but I don't think that changes the natural perception delay for hearing the lower frequencies; still have to have some cycles to do it, and in that time the high frequencies have already been heard.

I don't follow why nothing below 13.5KHz... the cycles of low frequency needed for perception don't have to occupy a line of sight space, just need the pulse times to cycle the eardrum of the listener.

Precedence and Haas I have read about. I don't think they address my questions.

The only review I found of the book you recommended is not complimentary, not familiar with this editor [*-)] http://www.en-genius.net/site/zones/endZONE/columns__book_reviews/book0212

The answer of "No" was to ALL of it!

And the book review based on some bozo's emotional preference for the word "audio" versus "sound", and not liking any text to enter a 3rd edition.

And bemoaning that a book on acoustical physics/engineering has, wait for it, "Math"! You can certainly pick 'em.

Try the Amazon reviews. And to think they added digital signal processing to the book and in the porcess included some ...here it comes again..."math!" Perhaps more cartoons would have been appropriate. But I guess they missed the readership and reviewers.

You are welcome to question the foundations of acoustical physics all you like, and in the process I guess question Heyser, et al. But please take a few minutes and familiarize yourself with the basics of modern acoustics.

[oldbuckster]

GEE, Whatever happened to Just Listening to Music ?????

[pauln]

Defiant non-answers, appeals to authority, not so veiled ad hominem attacks... that's it?

Please take a few minutes and familiarize yourself with the basics of modern discussion.

[PrestonTom]

MAS, You are on a quest and perhaps have missed what my point was regarding "accuracy".

The charming thing about the review was Heyser's epiphany that the bass was was in fact accurate (car door slamming sounded like a car door slamming). He further commented (IIRC) that maybe what he had grown accustomed to in terms of a "fuller bass", may have been that he become accustomed to listening to distortion being produced by the (other) speaker cabinets.

If the recording can be done with some fidelity, I am suggesting that using naturalistic sounds (from our backyard) may be quite useful in evaluating our home stereo systems. I think most folks have a better idea of what a car door slam sounds like as opposed to a symphony (with a good deal of post processing). It is a different way of thinking about the quality of our audio systems. My strong assumption of course is that the goal is faithful reproduction (accuracy, with warts & all)

Certainly, I am not suggesting this as a replacement for a diagnostic signal to measure time-alignment, crossover design, and other problems. I guess I am making a distinction between evaluating and diagnosing.

Good Luck,

-Tom

[mas]

Defiant non-answers, appeals to authority, not so veiled ad hominem attacks... that's it?

Please take a few minutes and familiarize yourself with the basics of modern discussion.

If you want to discard and ignore what is well understood in acoustics, that is fine.

But to expect us to go back and begin the search to reinvent acoustical physics based upon a random emotional assumption is a goal you will have to pursue on your own.

If you want to strike out on a rediscovery of acoustics, that's fine; but ignorance of acoustical physics, even if it is proclaimed, is not a rebuttal for things that are well understood. And simply making things up based upon one's subjective feelings is not a substitution for intelligent informed discussion.

The difference is that I am not off flying by the seat of my pants postulating on how things might behave. What I am suggesting is well documented and verified. And it has been scrutinized by many many eminently qualified professional folks. An "appeal to authorities"? Heaven forbid we refer to established precedence.

So, may I suggest that you start another thread to speculate regarding your exploration of things acoustic. They have little to no bearing upon what Heyser and others have postulated. And THAT was the discussion. ...Not the non sequitur dismissal of the behavior of acoustical phenomenon in the time domain. Oh oh, another reference to established precedence and references.

Is this a 'personal' attack? Hardly.... But it is in reference to one. And it is an acknowledgment that pure speculation is not a rebuttal to valid observation and proven methods of remediation of a problem. Your position might be better supported by citing a few more 'authoritative sources' that challenge the initial points made in the the Heyser article and the established use of signal alignment to assist in the resolution of such issues..

[bodcaw boy]

Now .. Mark ...

I .. should caution you ...

the JBL 4430's ... sound much better w/ the Passive X-Over ...

never got a electronic one to better that

look at JBL's electric model of phase relationships in the X-Over

see.......i warned you......

have a blessed day,

roy

[Coytee]

GEE, Whatever happened to Just Listening to Music ?????

Gots to have Jubilees now before you can be such a simpleton!

[]

[bodcaw boy]

see coyotee-o,

i told you so.....

have a blessed day,

roy

[DrWho]

That's a great point Tom. In fact, the Khorn has been one of the most annoying speakers I've come across because of that very fact...(and the Heyser article got me thinking about it)

Just curious and not being critical, but you are very clear in the Klipsch speakers that you don't like. What do you like?

I meant annoying in a good way...(well, good way for the speaker).

[DrWho]

Dr. Who ..

You should find it interesting that R. Heyser states the KH bass bin .. needs 8ms alignment ..

didn't we always talk 7 ms...?? in the Ball Park, baby ..[]

The real trick would have been dialing it in by ear. []

By ear??

...Bunch of freakin' Luddites!

Nothing Luddite about it. If there is an audible difference, then one will be able to hear the difference and line it up by ear. Granted it's easier to do with the proper tools, but if it is outside the realm of being able to do it by ear, then why bother in the first place? I say it all rhetorically because I've heard the differences that can be made, but the implication of it being audible is absolutely important.

[oldbuckster]

GEE, Whatever happened to Just Listening to Music ?????

Gots to have Jubilees now before you can be such a simpleton!

[]

Simpleton .................... OUCH !!! ................. Uncalled for ............. BAN COYTEE NOW

[Arkytype]

Fini,

I'd rather read the carnage--er discussions from the sidelines.

Miz Paula & I will definitely be at the next Klipsch gathering--hope to see your brood there, too.

Lee