Has anyone ever auditioned coincident loudspeakers?

[3db]

If so, what was the model and what were your impressions

http://www.coincidentspeaker.com/speakers.htm

 

[Rickster71]

You've got me wondering also.
With only seven dealers in the USA; I think there are more Big Foot sightings, than dealers.

 

[3db]

You've got me wondering also.
With only seven dealers in the USA; I think there are more Big Foot sightings, than dealers.

*L* Maybe he owns a pair or two

 

[WmAx]

If so, what was the model and what were your impressions

http://www.coincidentspeaker.com/speakers.htm

Does this manufacturer just make up things as they go along? Just two things I glanced at(I did not read their page any further past these two items):

"- Enclosure Tuning: All Coincident enclosures are tuned to a very high fundamental resonance frequency of 350 hz, (as opposed to the 80 hz resonance of most speakers). This high frequency tuning technique renders resonances sonically benign and inaudible. Resonances are effectively dissipated out the enclosure and transformed to thermal energy. The end result is an enclosure with no audible colorations."

I was not aware that resonances 'tuned' to 350Hz were "benign and inaudible". Nor is it likely a single primary 350Hz resonance is present, but looking at that enclosure design, a spread spectrum of resonances would be present due to the assymetrical bracing spaces at points. The 350Hz quoted falls squarely into well known band of audibility of resonances. They claim the higher resonant frequency is less audible. Yet, the credible perceptual research I have seen, find signals lower(less then about 2kHz) to become progressively less audible, all the way to the lowest frequency I have seen studied in this regard(About 100-130Hz) by Fryer and Toole. So in fact, 80Hz resonance would probably be less audible at a given amplitude as compared to a resonance of equal magnitude at 350Hz. Seems they at least understand the functional reason for increasing stiffness is reduced flexure amplitude, which is true. They seem to be making extra stuff up out of thin air to add to the page, though. As to their claims of most enclosured are tuned to 80Hz; I don't know where they get this data. Analysis of vibrational spectrum data from random hi-fi speaker cabinets as can be found in Stereophile's database reveals average resonances from about 100-800Hz range, with most speaker cabinet systems seeming to fall into the 200-500Hz bandwidth. It is not the common 'hi-fi' enclosure that resonates at 80Hz or below, though I'm sure you can find many low priced Big Box store speakers with this feature, due to the relatively thin walls with large relative surface area with minimum bracing as commonly found on such low price economy speakers. Perhaps they meant the economy range of speaker - despite that one may assume they mean to compare to other 'high-end' models.

"- Elimination of Internal Damping - Instead of using inexpensive, resonant enclosure materials and then futilly attempting to damp out resulting resonances and colorations with soft, spongy interior substances, (which are responsible for decreasing system sensitivity and increasing internal reflections). Coincident enclosures are constructed of inherently non resonant, incomparably rigid materials that require no damping with its accompanying deleterious affect on sound quality"

Now this is beyond absurd. The way I read it, they are using no(!) internal damping materials(soft spongy interior substances). They just claimed this material increased(?) internal reflections and that "rigid materials that require no damping". This is a completely different resonance(standing wave resonances) as compared to the cabinet resonances, and yet, they talk as if they are the same.

I can probably read further and find other completely absurd claims -- but this is quite enough already.

It may be that this page is produced entirely by the marketing department with no fact checks back to the engineering department.

One thing seems clear, someone associated with this is incompetent.

-Chris

 

[3db]

Does this manufacturer just make up things as they go along? Just two things I glanced at(I did not read their page any further past these two items):



I was not aware that resonances 'tuned' to 350Hz were "benign and inaudible". Nor is it likely a single primary 350Hz resonance is present, but looking at that enclosure design, a spread spectrum of resonances would be present due to the assymetrical bracing spaces at points. The 350Hz quoted falls squarely into well known band of audibility of resonances. They claim the higher resonant frequency is less audible. Yet, the credible perceptual research I have seen, find signals lower(less then about 2kHz) to become progressively less audible, all the way to the lowest frequency I have seen studied in this regard(About 100-130Hz) by Fryer and Toole. So in fact, 80Hz resonance would probably be less audible at a given amplitude as compared to a resonance of equal magnitude at 350Hz. Seems they at least understand the functional reason for increasing stiffness is reduced flexure amplitude, which is true. They seem to be making extra stuff up out of thin air to add to the page, though. As to their claims of most enclosured are tuned to 80Hz; I don't know where they get this data. Analysis of vibrational spectrum data from random hi-fi speaker cabinets as can be found in Stereophile's database reveals average resonances from about 100-800Hz range, with most speaker cabinet systems seeming to fall into the 200-500Hz bandwidth. It is not the common 'hi-fi' enclosure that resonates at 80Hz or below, though I'm sure you can find many low priced Big Box store speakers with this feature, due to the relatively thin walls with large relative surface area with minimum bracing as commonly found on such low price economy speakers. Perhaps they meant the economy range of speaker - despite that one may assume they mean to compare to other 'high-end' models.



Now this is beyond absurd. The way I read it, they are using no(!) internal damping materials(soft spongy interior substances). They just claimed this material increased(?) internal reflections and that "rigid materials that require no damping". This is a completely different resonance(standing wave resonances) as compared to the cabinet resonances, and yet, they talk as if they are the same.

I can probably read further and find other completely absurd claims -- but this is quite enough already.

It may be that this page is produced entirely by the marketing department with no fact checks back to the engineering department.

One thing seems clear, someone associated with this is incompetent.

-Chris

I don't know if there marketing team is in touch with the engineering staff. I'd like to hear them despite of their marketing bull.

Totem is another manufacturer that springs to mind that doesn't use insulation in the traditional sense. They paint the interiors of their speakers with a Borosilicate damping material.

 

[WmAx]

I don't know if there marketing team is in touch with the engineering staff. I'd like to hear them despite of their marketing bull.

Totem is another manufacturer that springs to mind that doesn't use insulation in the traditional sense. They paint the interiors of their speakers with a Borosilicate damping material.

To fail to absorb/null the interior standing waves is a huge error which can only result in an inferior sound reproduction device.

It is not clear to me exactly what Totem uses, however. Surely it is not a flat and smooth plate of borosilicate glass. Perhaps a spun structure, such as fiberglass, or another similar structure with actual substantial acoustic co-efficient properties.

-Chris