Stereophile on Floyd Toole

[SEAWOLF97]

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https://www.stereophile.com/content/hoisted-your-own-petard

[Robh3606]

Interesting!


Take a look and read the review do not jump ahead!

https://www.stereophile.com/content/volti-audio-razz-loudspeaker

Rob :)

[RMC]

The Stereophile reviewer may have it wrong on Toole's actual background. He did Electrical Engineering at University of New Brunswick, Canada but his PhD in London was in Acoustics as i recall, hence his expertise in that field.

Toole's material referred to is actually called "Loudspeaker Measurements and Their Relationship to Listener Preferences" Parts 1 & 2, JAES, 1986. Dealing primarily with the correlation (or absence of it) between what is measured and its impact on sound preferred. On and off-axis responses appeared to be important matters.

Before that, i'm aware of: Mark F. Davis, What's Really Important in Loudspeaker Performance?, High Fidelity Magazine, June 1978, P. 53. Some MIT fellows testing the audibility of various speaker parameters and/or measurements of these. Frequency response and dynamic radiation pattern (power response) seemed to be it.

[Robh3606]

I generally am on the Stereophile site a couple times a month to see what they have reviewed read the columns and stay current with whats new. On the topic of Toole and "classic speaker design" and how some do not adhere to those principles, I found it timely to say the least. It really address's one of their latest reviews and comments posted after from some of the readers. If you read the review and then look at the posted comments it really nails things as far the designer being criticized based on the measurements. Reading the designers comments he simply doesn't care about how the measurements look. He designs by what he hears and likes.

Here are the measurements from the review that are completely the opposite of the "classical" approach Toole's research recommends.

Rob:)

[RMC]

In a way, designing by ear and sound preference does not necessarily lead to a frivolous design.

What does the black response curve shows? Roughly, boosted bass, a dip in Mid and increased HF.

Then, what does the Fletcher-Munson equal loudness curve has shown us? The opposite. Roughly, the ear is less sensitive to LF, more sensitive to Mid, and less sensitive to HF.

Seems to me that's pretty much how the designer went by doing the opposite of the Fletcher-Munson curve. It ain't stupid, more or less design by ear sensitivity. Giving a PERCEIVED flat or so response.

Did part of this (on mid) with two pairs of smaller sound reinforcement boxes i made and don't regret it.

[Robh3606]

It's a tone control. It's basically the old equalizer smiley curve. If that's what you want fine. The comb filtering is easilly avoidable and if you look at the rest of the review you can see just how serious it is. It's consistent in the off axis plots as well.

The main issue was that the measurements were essentially weaponized against the designer. I have an engineering background so that would be completely unacceptable to me in any DIY speaker that I built.

I am very curious exactly what they sound like especially using the toe-in used in the review and recommended from the designer for near field listening. In that case you would be considerably off axis which would change the perceived balance but not the overall power response.

Rob:)

[Ed Kreamer]

Colleagues:

Fascinating discussion and somewhat revealing.

1 regarding the article on Dr. Toole by Jim Austin; that he (Austin) protests too much methinks. I'm not quite certain what he is getting at. The comments at the end of are of interest also.

2 regarding the Volti speaker; The graphs show an expensive speaker that displays non linear frequency response. While the plot may resemble the Fletcher-Munson curves, the curves are supposed to flatten out when the volume is turned up. Our late colleague John Eargle once remarked that music should be played back at realistic sound levels. By the published curve that thing, at realistic levels, would fry eggs on the sidewalk in January. I thought that the Volti company was formed.in part to correct some of the excesses the earlier Klipsch products displayed. Or am I confusing Volti with Bob Crites.


My take is that non linear behavior is acceptable as long as it is an audiophoole approved product

Sorry Rob I didn't notice what you wrote. My guess that he would be trying to get past the -6dB point on the horns.

I see the sun is past the yardarm time for wine

Ed

[grumpy]

Think it was the other way round... -added- excess to Klipsch products (fancy veneer) at the start... and a good marketing sense. Long since evolved from there, particularly in the latter.

It's an open market. Stuff sells or it doesn't. Seems to have found a niche.

[Ed Kreamer]

Indeed, so it has. If it sells it sells.

[Robh3606]

Sorry Rob I didn't notice what you wrote. My guess that he would be trying to get past the -6dB point on the horns.

Hello Ed

Yes I agree but looking at the polars it's still going to be difficult to find that sweet spot!


It's an open market. Stuff sells or it doesn't. Seems to have found a niche.

So true but it is surprising to me. One off these days I would like to hear a pair just out of curiosity.

Rob:)

[Ed Kreamer]

I too would like to hear them. my 4410's would probably sound very subdued compared to them.

Well as Grumpy says;

".....stuff sells or it doesn't." But then, so does limburger.

[Mr. Widget]

Interesting!


Take a look and read the review do not jump ahead!

https://www.stereophile.com/content/volti-audio-razz-loudspeaker

Rob :)I think a lot of people on this forum would agree. The extremely dynamic speakers from Altec, JBL, and even Klipsch are exciting to listen to and can sound more like music than a clinically accurate and sluggish audiophile speaker.

Then again, if you can have a well controlled polar response, even frequency response, and excellent dynamics like some of the modern JBLs, you get a best of both words scenario.

Isn't that why we are all here? :bouncy:


Widget