Objections to speaker qualifications

[Theta]

Most notable speaker reviewers, like Erin categorise some speakers as being "point source, there is no such thing.
Point source is a microphone in reverse (1 microphone).
They also categorize some speakers as omnis which most audiophiles on this site and others put aside as non audiophile or non correctly engineered because they don't measure well on klippel, thus never recommended.
Comments are usualy demeaning, such as, If you like like them, it's your taste, but scientificaly they are trash.
An example is the large MBL's, the most advanced technology available in speaker design today, not coaxials (old tech with some improvements by Kef) which seem to have taken over the market.

 

[Blumlein 88]

Lots of straw-manning here. Setting up the idea omnis are demeaned when I've not seen that. I don't recall demeaning comments (calling omni speakers trash). Some members have MBLs or like them. They are in fact not optimum by the criteria of a spin-o-rama result. Aspects have been respectfully discussed regarding bipolar, dipolar and omni speakers. The owner of this site and many members do find spin results helpful in finding speakers that perform well in a room. This whole approach was developed of course by Toole et al at Harman and has become an international standard. ANSI/CEA 2034.

Point source like the KEF and similar are known to be quasi-point source or near point source. That is not news.

If you are objecting to using a Klippel (or the resulting spin-o-rama results) to measure speakers, then what would you suggest is superior?

 

[NTK]

MBL's aren't true omni. They are at best axially symmetric in the horizontal plane, but are definitely not vertically. And what qualifies them as "the most advanced technology"?

The term Dr Jack Oclee-Brown uses for coaxial driver is coincident source, not point source, meaning that the acoustic centers of the lower frequency driver and the higher frequency driver are (approximately) coincident. The advantage of coax drivers is that the horizontal and vertical dispersion is similar, with the absence of lobing (or significantly reduced lobing in the case of 3 or more ways with separate woofers) in the vertical plane.

 

[stoo23]

Ohm F's were True Omni's and it would be difficult to describe them as 'Trash' they were rather exceptional, when driven properly and were truly Unique !!

 

[thewas]

Ohm F's were True Omni's

Similarly to the MBL's they aren't true omni but at best axially symmetric in the horizontal plane, but are definitely not vertically.

 

[Theta]

MBL's aren't true omni. They are at best axially symmetric in the horizontal plane, but are definitely not vertically. And what qualifies them as "the most advanced technology"?

The term Dr Jack Oclee-Brown uses for coaxial driver is coincident source, not point source, meaning that the acoustic centers of the lower frequency driver and the higher frequency driver are (approximately) coincident. The advantage of coax drivers is that the horizontal and vertical dispersion is similar, with the absence of lobing (or significantly reduced lobing in the case of 3 or more ways with separate woofers) in the vertical plane.

Lobing is a term or adjective used by manufacturers to discredit speakers other than their own design. McIntosh, Infinity, Genisis and others with multiple drivers (some with as many as 30 drivers per side) designed by fully qualified Engineers are not bothered with comments and mesurements designed to show lobing as a major problem and intended to disqualify their design as erroneous.

 

[Ron Texas]

The large MBL's cost as much as a house, or a condo in pricey places.

 

[Theta]

The large MBL's cost as much as a house, or a condo in pricey places.

Cost is a problem, but when you compare them to Wilson's or focal which can be cloned by any decent DIY amateur, they are some what of a bargain.

 

[Vladimir Filevski]

Lobing is a term or adjective used by manufacturers to discredit speakers other than their own design. McIntosh, Infinity, Genisis and others with multiple drivers (some with as many as 30 drivers per side) designed by fully qualified Engineers are not bothered with comments and mesurements designed to show lobing as a major problem and intended to disqualify their design as erroneous.

Nonsense!
Acoustic lobing is an actual problem, as a result of simple interacting of two or more waves coming from two or more sound sources. Some Engineers (more than just "fully qualified"!) were bothered by the bad sound (and bad measurements, also) of lobing, so they find how to improve radiation form multiple sources - by "shading" drivers output, by curving the front baffle or by delaying the output on some drivers, etc.

 

[NTK]

Lobing is a term or adjective used by manufacturers to discredit speakers other than their own design. McIntosh, Infinity, Genisis and others with multiple drivers (some with as many as 30 drivers per side) designed by fully qualified Engineers are not bothered with comments and mesurements designed to show lobing as a major problem and intended to disqualify their design as erroneous.

I agree that some vertical lobing is not a major problem. It only reduces the listening window.

Since lobing isn't an issue for you, then what is the point for omni speakers like MBL's which you claim is the "most advanced technology"? It doesn't take their contraption to spray sound all around.

 

[Ron Texas]

Cost is a problem, but when you compare them to Wilson's or focal which can be cloned by any decent DIY amateur, they are some what of a bargain.

You have a novel way of defining what a bargain is.

 

[Theta]

I agree that some vertical lobing is not a major problem. It only reduces the listening window.

Since lobing isn't an issue for you, then what is the point for omni speakers like MBL's which you claim is the "most advanced technology"? It doesn't take their contraption to spray sound all around.

Quite the contrary, if you read or listen to Erin's review of the Kef, he says coaxials give a better but not great vertical dispertion. Most well designed so called Omis whether true omnis or half reflective omnis give the best vertical dispertion by definition, and completely eliminate the need to have the tweeter at ear level at all times, a non acceptable trade off for some of us.

 

[Titurel]

Point source like the KEF and similar are known to be quasi-point source or near point source. That is not news.

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.

 

[Petrushka]

***cough*** 901s

 

[Vladimir Filevski]

Quite the contrary, if you read or listen to Erin's review of the Kef, he says coaxials give a better but not great vertical dispertion.

You are confusing lobing with dispersion.
Vertical dispersion in any coaxial is the same as horizontal.

 

[Theta]

You are confusing lobing with dispersion.
Vertical dispersion in any coaxial is the same as horizontal.

Not acording to Erin, see his video on the Kef Blade 2 his favorite all time best ever bar none.

 

[Jim Taylor]

Quite the contrary, if you read or listen to Erin's review of the Kef, he says coaxials give a better but not great vertical dispertion. Most well designed so called Omis whether true omnis or half reflective omnis give the best vertical dispertion by definition, and completely eliminate the need to have the tweeter at ear level at all times, a non acceptable trade off for some of us.

I disagree.

Jim

 

[Theta]

I disagree.

View attachment 379868

Jim

Nice one, a crapy french speaker from the 70's, to make your point. Since I am watching tennis at the moment "you cannot be serious" is my comment.

 

[Jim Taylor]

Nice one, a crapy french speaker from the 70's, to make your point. Since I am watching tennis at the moment "you cannot be serious" is my comment.

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

 

[Vladimir Filevski]

Not acording to Erin, see his video on the Kef Blade 2 his favorite all time best ever bar none.

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.