Objections to speaker qualifications

[Vladimir Filevski]

Nice one, a crapy french speaker from the 70's, to make your point.

Crappy? Why? Because it has enormous lobing (which is not important according to you)?

 

[Theta]

You are still confusing lobing with vertical/horizonal dispersion. By design/nature, coaxials have identical horizontal and vertical dispersion in their working bandwidth. Lobing require two drivers (two sound sources) vertically separated. Coaxials have two coincidental drivers, so no lobing there.
I read Erin's review and saw all his measurements - nothing there support your assertion (which is clear as mud). On the contrary.

Watch the first part of the video, he always starts with his subjective evaluation before going to his measurements.

 

[Theta]

Crappy? Why? Because it has enormous lobing (which is not important according to you)?

Crappy because I have heard these speakers, I will lay 100 to 1 odds that you have never heard or even seen these speakers which were a dismal failure, I don't think they sold more than 200 pairs.

 

[Petrushka]

Those are Design Acoustics D12 speakers, made in California. I must admit, though, that I don't know where Design Acoustics main offices were located.

Jim

D12s last sold for $2000 on US Audio Mart. A few years ago.

 

[Blumlein 88]

How is quasi-point source or near point source superior to faux point source, absent a hard metric showing relevant performance deviation from an actual point source. All quasi or near tells us is something we already know, an actual point source transducer is an engineering impossibility, and, until a hard metric can be applied (invented, agreed upon) indicating deviation from the ideal, point source and all its qualified kin are no more rigorous than omnidirectional for describing their real world approximations, only marginally more candid.

I can see the OP's point. Spinorama provides useful data, not a final answer or even a useful answer without a fair amount of interpretation. You can't simply punch Spinorama's output into a cost/benefits formula. Goodness is still in the eye (and heuristics) of the beholder.

I'm going to suggest you don't understand directivity. It is symmetrical or nearly so with near point source or more correctly coincident drivers. That is measurable and not something in the eye of the beholder.

 

[Theta]

D12s last sold for $2000 on US Audio Mart. A few years ago.

I stand corrected, I auditioned these speakers at an audio show at the hotel Sofitel in Paris, and they got a lot of press La Revue Du Son.

 

[Blumlein 88]

So far it appears the OP is simply trying to convince us subjective listening impressions reign supreme. He thinks he is being stealthy in his approach.

 

[Titurel]

I'm going to suggest you don't understand directivity. It is symmetrical or nearly so with near point source or more correctly coincident drivers. That is measurable and not something in the eye of the beholder.

I would counter that your understanding of it is incomplete or conveniently selective, as you very nearly conflated coincident driver - a construction consideration I didn't mention with point source (a chimera) which I did. While coincident drivers can mimic a point source over some range of dispersion (and of frequency) they are not point sources, which are inherently omnidirectional. Question for you: where do you stuff the drive goodies in a point (source), a non-object possessing no physical dimension (only location), let alone, where does one attach the power cables?

As for my understanding of directivity, Years ago, I owned a mic set-up bearing your moniker. (a pair of AKG C414 TL 2), a lovely study in selected directivity all by itself.

 

[Killingbeans]

And what qualifies them as "the most advanced technology"?

I'm thinking the same. It's still a traditional motor + voice coil, just exciting a "ballon" instead of a cone?

It's novel and more difficult to fabricate for sure, but calling it "advanced technology" would be a stretch.

 

[Salt]

Novel? On the market for more than 30 years. For a car that's Oldtimer status here.

 

[NTK]

I'm thinking the same. It's still a traditional motor + voice coil, just exciting a "ballon" instead of a cone?

It's novel and more difficult to fabricate for sure, but calling it "advanced technology" would be a stretch.

The method of generating sound pressure is by flexing some curved pieces of metal strips. The outward moving "diaphragm" motion that creates the sound pressure is therefore non-uniform along the length of the metal strips, which makes the radiation pattern of the sound pressure more complicated. I am far from convinced that it is a good thing.

 

[FrantzM]

Wrong place to come unprepared for serious arguments ...

Peace.

 

[Blumlein 88]

I would counter that your understanding of it is incomplete or conveniently selective, as you very nearly conflated coincident driver - a construction consideration I didn't mention with point source (a chimera) which I did. While coincident drivers can mimic a point source over some range of dispersion (and of frequency) they are not point sources, which are inherently omnidirectional. Question for you: where do you stuff the drive goodies in a point (source), a non-object possessing no physical dimension (only location), let alone, where does one attach the power cables?

As for my understanding of directivity, Years ago, I owned a mic set-up bearing your moniker. (a pair of AKG C414 TL 2), a lovely study in selected directivity all by itself.

Do you know how the Quad ESL 63 worked? It was quasi point source while being a dipole. That approach could create a point source. It is at least in theory possible to create something effectively a point source over a certain frequency range without actually being an infinitesimal point. Woofers being one example. It would be possible to create a point source from several coincident drivers arrays.

 

[MAB]

I stand corrected, I auditioned these speakers at an audio show at the hotel Sofitel in Paris, and they got a lot of press La Revue Du Son.

No problem on getting the basic facts on these speakers wrong.
The troubling part is you think your anecdotal impressions from listening to them in a hotel in Paris is a valid way of assessing the sound.

 

[Ron Texas]

This discussion contains some very unscientific claims.

 

[Blumlein 88]

This discussion contains some very unscientific claims.

Everyone knows you can't use science to design speakers. Antenna arrays, radar and such sure. But not speakers.

 

[Titurel]

Do you know how the Quad ESL 63 worked?

Sure, I heard one of the first units shipped to the US. (Yeh, I'm that old) Still, it did not create a point source nor did it exhibit the radiation of a point source. As you state in your post, it's a dipole and I'd say a helluva clever design. Still, one can't make a point source with multiple drivers. (Do I hear a head on collision between Maxwell and Euclid?) An audio point source (again, a chimera) cannot be limited as to directivity nor bandwidth. Now, If someone would create a simple spec. specifying transducer "point-sourci-ness" over some frequency within a given directional spread (radiation pattern), we might have something, but still no true point source radiator.

 

[RayDunzl]

Everyone knows you can't use science to design speakers.

I'm not sure I can listen scientifically, so...

Had a nice lady from Louisiana listen to my gear in Houston in 1994 or so, during a hamburger lunch i put on for friends at the office.

Asked her what she thought, she said, in her best Cajun accent, "I don't listen intellectually."

 

[Titurel]

I wonder: how much does time dilate near a point source speaker?

 

[Vladimir Filevski]

Crappy because I have heard these speakers, I will lay 100 to 1 odds that you have never heard or even seen these speakers which were a dismal failure, I don't think they sold more than 200 pairs.

You didn't notice my sarcasm...
Your main point was - lobing is not important at all:

Lobing is a term or adjective used by manufacturers to discredit speakers other than their own design.

So, how is it possible this speaker to sound crappy to you, when it is the epitome of maximum possible lobing?