Jump to content
The Classic Speaker Pages Discussion Forums
Sign in to follow this  
Zilch

The Goals for an "Ideal Loudspeaker"

Recommended Posts

Oh, I totally agree and add that the 'lines in the sand' will vary based on human variability and listening tastes.

Another common wisdom, that everyone hears differently.

Studied under controlled conditions, statistically, we are surprisingly uniform in our preferences.

Linkwitz says it a different way: "It's not that we hear differently, rather, that we LISTEN differently."

Here is Toole Part 2, which I read for the first time last night:

http://www.aes.org/e-lib/download.cfm?ID=5...amp;name=harman

Completed 25 years ago, these studies WERE done in a prototype of the standard IEC listening room. The conclusion:

There are two principal conclusions to this work. The first is that, given adequate preparation and experimental controls, listening tests can yield reliable subjective data and that listeners with good hearing performance agree closely on the relative merits of loudspeakers. The second is that the loudspeakers preferred by these listeners are those exhibiting measured performances that are superior in certain well defined respects.

Given the proper circumstances, experienced listeners with normal hearing prefer loudspeakers with wide bandwidth, flat and smooth amplitude response, and uniformly wide dispersion.

Thank you for the reference citation, Pete.... :)

In the light of prior discussions here, I ask the appropriate question: "What does 'uniformly wide dispersion' mean in the context of these studies?" Constant directivity, clearly, by my view, but how wide?

Help me with the math, but I believe a 90° axisymmetric section would define a Q of 8 and a DI of 9. Thus, it may be seen that in the top octave, virtually none of the speakers studied had dispersion as wide as what Geddes would call "narrow" dispersion today; they're all beaming up there.

It's quite frustrating. Here's what was posted as counter to my conclusions from data regarding AR4x just yesterday:

Don't worry too much about microphone measurements or curves and other such data. These speakers are legendary for their ability to portray music, regardless of measurable parameters.

Microphones and hard data collection are useful tools for speaker builders however.

[Can I get a little sympathy here, please? :P ]

Share this post


Link to post
Share on other sites
In the light of prior discussions here, I ask the appropriate question: "What does 'uniformly wide dispersion' mean in the context of these studies?" Constant directivity, clearly, by my view, but how wide?

I think Toole waffles a bit on directivty and power response. His data clearly shows that any manner of power response can be well liked. I think his primary belief is that power response is a great revealer of resonances (if they survive averaging of all angles then they are resonances, rather than reflections). He stops short of saying that power response is totally irrelevant, although several times he clearly states that it is a poor indicator of ranking.

If power response is of marginal use then directivty index is also suspect. The key issue here is "necessary and sufficient" criteria.

David

Share this post


Link to post
Share on other sites
If power response is of marginal use then directivty index is also suspect. The key issue here is "necessary and sufficient" criteria.

I don't believe the mutual exclusivity of imaging and spaciousness is one of the "common wisdom in error" things. Maybe "reciprocity" is a better characterization, but it's well documented in the literature. It's also well documented, however, that given the facility to do so, listeners will dial up spaciousness at the expense of imaging and even spectral quality, to levels well beyond what occurs in reality, like listening in a reverberant chamber.

Part 1 of that paper quite clearly reveals that Bose and Villchur/Allison were very much sympathetic contemporaries in playing the "Power Response Is King" tune.* We now know that it's possible to manipulate imaging and spaciousness independently by separating the cues using controlled directivity, a major element in establishing room independence. I'm very much tempted to set up Ken's "Magic" speakers for experiments here. :P

*A protracted debate in another forum came to rapid closure with this revelation some while ago.

[Admittedly, a low blow.... :) ]

http://www.audiokarma.org/forums/showthread.php?t=219604

Share this post


Link to post
Share on other sites
It is well-established but not widely appreciated outside the industry and scientific community that when examined under controlled conditions, among subjects with "normal" hearing abilities, listener loudspeaker preferences are surprisingly uniform, and correlate well with objective measurements. The metrics are more complex than on-axis frequency response alone, but that plays a significant role in virtually all of them (some are proprietary,) and even just that reveals considerable information about the character of the sound produced. We don't have to look much further than there to know why VOTT sounds the way it does, for example, and how to "fix" that, if desired. The general set of objective parameters which describe "listener-preferred" loudspeakers is well known and finds universal application throughout the loudspeaker manufacturing industry today. See Toole.

The analogies commonly cited are imperfect, of course, and frequently misapplied in discussing loudspeaker preferences. The fundamental performance objective is well-defined: reproduce the program as faithfully as is possible, which has comprised the very essence of "high-fidelity" from the outset, and it should not matter whether our tastes go to Pink Floyd or Rubinstein. That's the apples vs. oranges element in this -- do you like all of your wines sparkling? Tang vs. freshly squeezed? Can we really not believe it's not butter? Once again, when subjected to critical examination, statistically, what we want is "accurate," and that separates what is better from the not-so-good. "All the sugar and twice the caffeine" may be fun, but it's not representative of the central tendency here. We can certainly measure it, though, and know it for what it is.

YO, PETE!

See posts #154 and #157 in that AK thread.

[Props for finding the same images here in The Kitchen.... :P ]

Share this post


Link to post
Share on other sites

With which, I submit genre independence for consideration as Goal #2.

If we want "twice the caffeine," that's what EQ is for.

[but let's call it "Soundfied Management" (SM) here.... :P ]

Share this post


Link to post
Share on other sites
With which, I submit genre independence for consideration as Goal #2.... :P

I wonder how many people here actually switch speakers for different types of music. I only have one set per system, and all I ever do for different recordings is adjust the tone controls a bit now and then. That includes different recordings within the same kinds of music, btw. The closest thing to a change in default settings for types of sources is when I switch between analog and digital sources.

Share this post


Link to post
Share on other sites

Soundminded observes that, in detail, the parameters must be adjusted for virtually every cut. He's not the first to suggest this.

On the larger scale, however, there's a conspicuously large gap between what are considered rock (L100) vs. classical (AR3a) speakers. Call it west vs. east coast perhaps, but each may be characterized by their respective coloration.

Is it inconceivable that an ideal loudspeaker could play either or both with equal aplomb? :P

Share this post


Link to post
Share on other sites
With which, I submit genre independence for consideration as Goal #2.

If we want "twice the caffeine," that's what EQ is for.

[but let's call it "Soundfied Management" (SM) here.... :P ]

We've also referred to soundminded as SM on occasion. I hope your new acronym doesn't confuse everyone.

Share this post


Link to post
Share on other sites
We've also referred to soundminded as SM on occasion. I hope your new acronym doesn't confuse everyone.

It's humor from the Zilchster; they are very much the same.

[O.K., "SFM," then.... :P ]

Share this post


Link to post
Share on other sites
Soundminded observes that, in detail, the parameters must be adjusted for virtually every cut. He's not the first to suggest this.

On the larger scale, however, there's a conspicuously large gap between what are considered rock (L100) vs. classical (AR3a) speakers. Call it west vs. east coast perhaps, but each may be characterized by their respective coloration.

Is it inconceivable that an ideal loudspeaker could play either or both with equal aplomb? :P

If we assume that the respective colorations are essential to getting the sound "right," then I would say it couldn't happen, at least not without applying EQ. OTOH, rock music played through classic ARs has always sounded just fine to me (if I have visitors with "west coast" preferences, I tell them to just wait until I'm out of the room and then press that button marked "Loudness"), while classical music played through "west coast" speakers usually makes me want to reach for the bass and treble controls (to turn both down). So from my totally subjective POV, the speakers I have do in fact play both "with equal aplomb." Ultimately, it seems to me that "east coast" and "west coast" reflect the subjective preferences of listeners (myself included) rather than any objective requirement of a music genre.

I would be inclined to agree with the "EQ every record" philosophy if objective data about what settings are required for every record came with it. In the absence of this, EQ'ing is still just an exercise in tailoring sound to a listener's subjective view of what sound is "right," and while I might eventually be able to do that for a Rubenstein recording made in a symphony hall I"m familiar with, when it comes to adjusting for Pink Floyd in any venue I'd be utterly lost.

Share this post


Link to post
Share on other sites
Soundminded observes that, in detail, the parameters must be adjusted for virtually every cut. He's not the first to suggest this.

On the larger scale, however, there's a conspicuously large gap between what are considered rock (L100) vs. classical (AR3a) speakers. Call it west vs. east coast perhaps, but each may be characterized by their respective coloration.

Is it inconceivable that an ideal loudspeaker could play either or both with equal aplomb? :P

I am still of the opinion that a speaker's coloration is due in some measure to what the drivers are made of - all other things being equal (if that's even possible)

Share this post


Link to post
Share on other sites
I am still of the opinion that a speaker's coloration is due in some measure to what the drivers are made of - all other things being equal (if that's even possible)

The are certainly selected for achieving the particular design objective. The question is whether if selected for "neutral," instead, could these multiple purposes be served via other means?

Are studios "tailored" to produce a specific musical genre? Is monitor selection a significant part of that formula, if there is one? :P

Share this post


Link to post
Share on other sites
I am still of the opinion that a speaker's coloration is due in some measure to what the drivers are made of - all other things being equal (if that's even possible)

Was there any substantial change in what JBL drivers were made of between the 50's and 70's? I heard a lot of classical music played through some tube-powered Hartsfields when I was growing up, and the sound didn't seem terribly 70's "westcoast-y" at all.

Share this post


Link to post
Share on other sites
Was there any substantial change in what JBL drivers were made of between the 50's and 70's? I heard a lot of classical music played through some tube-powered Hartsfields when I was growing up, and the sound didn't seem terribly 70's "westcoast-y" at all.

Yes, very much so, although forward mids were always "featured...."

Share this post


Link to post
Share on other sites
Yes, very much so....

Chicken and egg time: did JBL change the drivers because they needed to in order to meet a new sound design goal, or did the sound of JBLs change because they needed to change the drivers for some other reason...?

Share this post


Link to post
Share on other sites
Chicken and egg time: did JBL change the drivers because they needed to in order to meet a new sound design goal, or did the sound of JBLs change because they needed to change the drivers for some other reason...?

JBL stepped in it, basically.

They designed a small nearfield monitor to mimic the inaccurate Altec 604, standard studio monitor at the time.

Engineers liked it and took them home, creating a demand for boomy bass.

Consumers liked it for rock, and the rest is history....

Share this post


Link to post
Share on other sites
The are certainly selected for achieving the particular design objective. The question is whether if selected for "neutral," instead, could these multiple purposes be served via other means?

Are studios "tailored" to produce a specific musical genre? Is monitor selection a significant part of that formula, if there is one? :P

Okay, let's set aside the measuring equipment and....

..... do a coloration listening test comparing let's say a heavy, felted woofer (ala 3a type) against a modern PP cone type. AR themselves migrated from the former to latter over the course of 10-15 yrs.

Also look at the midrange colorations with a PP cone mid vs say a graphite, wood, titanium, kevlar type cones.

Share this post


Link to post
Share on other sites
JBL stepped in it, basically.

They designed a small nearfield monitor to mimic the inaccurate Altec 604, standard studio monitor at the time.

Engineers liked it and took them home, creating a demand for boomy bass.

Consumers liked it for rock, and the rest is history....

So what year did this happen? I might not want to let JBLs posted for sale go by uninspected if they're earlier than that fateful event...

Share this post


Link to post
Share on other sites
So what year did this happen? I might not want to let JBLs posted for sale go by uninspected if they're earlier than that fateful event...

http://www.audioheritage.org/html/profiles/jbl/l100.htm

But don't assume that's all that JBL made subsequently, or even contemporaneously; by 1980 they were emphasizing accurate designs, and "west coast" was all but history. Enter David Smith, et al....

Share this post


Link to post
Share on other sites
http://www.audioheritage.org/html/profiles/jbl/l100.htm

But don't assume that's all that JBL made subsequently, or even contemporaneously; by 1980 they were emphasizing accurate designs, and "west coast" was all but history. Enter David Smith, et al....

For some reason I've never experienced much enthusiasm for post 70's speakers, and that includes the efforts of the "east coast" makers like AR. I don't know if it's only that I don't like the sound, of if it's a prejudiced continuation of my distaste for the appearance of speakers made without real wood in their cabinets or natural fabrics in their grilles.

Share this post


Link to post
Share on other sites

If so, it's not "about the music," then, rather, the meaning.

Pick yer pleasure:

post-102716-1272770806.jpg

Share this post


Link to post
Share on other sites
If so, it's not "about the music," then, rather, the meaning.... ;)

It's definitely a holistic sort of experience. I've passed on any number of products with great reviews and even with sound I liked because I thought their appearance was butt-ugly. Like some manufacturers' whole product lines that only come in black.

Share this post


Link to post
Share on other sites

Not likely that "looks vintage" is going to make the list of goals for an ideal loudspeaker, but there might certainly be means to disguise it as such.

[Lots of folks brand me "pariah" for doing that, tho.... ;) ]

Share this post


Link to post
Share on other sites
Not likely that "looks vintage" is going to make the list of goals for an ideal loudspeaker, but there might certainly be means to disguise it as such.

If we were running blind testing, we could probably put them all behind a screen or turn out the lights...

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.
Sign in to follow this  

×