I think the advantage of open baffle is that you hear the drivers, and you avoid all the problems of the boxes trapping in soundwaves and resonating and vibrating.
Most designs tend to give a cardioid dispersion pattern, i.e. in front of and behind the speaker, but not much at the sides because of destructive interference as the soundwaves meet at the sides.
In this video, the reviewer compares on one of the main Spatial Audio open baffle speakers to one of the main open baffle kit designs from GR Research (that he built).
Open baffles are not revolutionary - they were the very first loudspeaker designs!
Cone drivers (other than those with their own totally enclosed rear chambers as with some midrange units and most tweeters) radiate approximately equally from the back as the front. With bare driver suspended in the air, some of the the air pushed forward by the cone simply rolls around the edge of the driver to the replace the air ‘sucked’ forward by the cone (and vice versa when the cone reverses), limiting the amount of air moving in the listener direction. This effect is more pronounced as frequency lowers, and seriously limits low frequency output. otger than a function holding the drivers in place.The first baffles in loudspeaker design were the first separate loudspeaker “enclosures” and were simply sheets of wood (i.e. no cabinet), as large as practicable, the purpose of which was to prevent that immediate flow of air round the driver frame. So e cancellation still takes place, while the nature of sound wave propagation dictates that the larger the baffle the lower the frequency where cancellation is significant. The baffle can also be folded backwards, creating an open back box, however that itself tgen starts to have its own effect, more pronounced the deeper the sides relative to front size.
The low frequency roll off, significant unless the baffle is huge (impractical in most domestic situations), is combatted in some designs by having high power capable bass drivers and proportionately increasing amplifier power output as frequency goes down, or by using a separate subwoofer (not open baffle). The other key potential issue of open baffles is that the rear radiation reflects of the wall behind, far more significantly so the higher the frequency compared to an enclosed box. This means that to avoid both comb filtering and muddling of sound from the reflections of that rear sound radiation, the speakers need to be a very long way forward of the rear wall, or have the rear wall very well treated to absorb it. Against these disadvantages, open baffles have the distinct benefit of no inherent resonant frequency(ies) as boxes have, and no internal compression as particularly problematic in smaller sealed boxes causing non-linearity of cone excursion and hence power distortion in sealed boxes.
Which design is better is something that can only be assessed by hearing - and given the rear radiation it is far more important than most speakers that the assessment is done in a one’s own room or otherwise in one of similar dimensions and with similar acoustic properties to the wall behind the speakers.
I posted this back in March on a thread titled “What’s inside” … the only piece of data missing from my post that’s relevant is that they’re positioned about 4 feet from the back wall and about 11feet from the listening chairs … and I think, but am not 100% sure, that they are available world wide … shipped to your door. Some assembly required.
Interestingly if you ask for a home demo they will ship you either a brand new set of speakers, which, if you like you can keep … OR … they will ship you an already broken in/run in set of speakers, which, if you like you have to ship back and they will replace them with a new pair.
I have never been happier with a set of speakers than these …
Frequency response 29Hz - 20KHz … 96db … fast crisp bass and a luscious mid range. No brightness or sharpness at all at the top.
It’s fair to say the speaker excels at all the genres of music I listen to but it goes above and beyond with male/female voices and acoustic, especially stringed, instruments. You are acutely aware of fingers being placed on strings before they are actually plucked or strummed. Cellos are rich and creamy …
My go to track when demoing a new piece of equipment is the first track on John Martyn’s “Church with one Bell” album … “He’s Got all The Whiskey” … the first time I played it through these speakers I came near well close to having a bad case of the moist eye … hugely emotional.
One thing to bear in mind is that the speakers currently on sale have different woofers than I do and they are using a different crossover. They are continuously improving on the product … I only add this tidbit in the interests of full disclosure …
Lastly, it’s a small operation; when you email the info@ email address more than likely you will get a response from the President of the company … Ze’ev Schlik … who is also founder and creative force behind the line of products … very knowledgeable and extremely helpful.
Thanks John Enjoy Peter
PS. Last time I heard a pair of open baffle speakers was back in the mid 80s in a hifi outlet in Copenhagen. They were an American make called Mirage driven by Mark Levison. Time flies….
ATB Peter
ATB Peter
? ATB Peter