KEF concentric drivers are a tweeter and mid combined... if you add another woofer/mid you forgo the directivity benefits of using the coax, which is the main reason to use one in the first place.
I thought you were referring to a KEF concentric driver. If so, it has both a tweeter and a midrange/woofer. To run that midrange/woofer in parallel with two other woofers probably would not work out too well for a number of reasons.
There is a lot of R&D in the KEF Blade. And, its concentric driver is their top tier driver. I am not aware of KEF even offering them for sale without actually buying the speakers themselves. If you are able to get your hands on a pair of those, I will be extremely impressed.
Indeed... if you do manage to get them, maybe don't post about it because someone will probably be getting fired or losing a distribution contract...
But, shoot me a private message letting me know where they were acquired so that I can get myself a pair.Indeed... if you do manage to get them, maybe don't post about it because someone will probably be getting fired or losing a distribution contract...
I don't know much about 3D printing, but if I imagine a double walled structure that had some sort of widely spaced matrix connecting inner wall to outer, seems it would increase overall stiffness of structure. Subsequently, I'd fill the created void with sand or perhaps two-part silicone like the stuff for casting molds. Could also be filled with epoxy, but that curing process creates considerable heat, which may be an issue, and I don't know if it would have noticeable effect on cabinet acoustics in the end. Although concrete seems like a good idea to some, I honestly don't see the benefits in this application. Natural Stone or Quartz countertop material has similar properties and would need to be damped somehow.
You mean SSC? Spontaneous Speaker Combustion?
That was the tweeter I was probably going to go with. The 25mm beryllium will give me the performance I wanted in terms of distortion.
What about KEF's other floor standing speakers? They also have other woofers. Now where they're crossed over I would have to look up.
Like sand bags or just outright sand?You mean SSC? Spontaneous Speaker Combustion?
The temp rise would be insignificant. Probably not even measurable without some really sensitive equipment. From science class I remember "energy cannot be created nor destroyed, only transformed". I have a subwoofer that I made with an MDF, sand, MDF sandwich. It remains at ambient temp with the tools I have at hand.
Loose sand. Commonly used for sandblasting and pool filters.
Yes, but ABS is not very stiff, modulus of elasticity is about half of MDF. And the structures you'd use in the void would be quite thin, so IMO they aren't really comparable to a solid-built MDF structure. Sand might really be OK in this situation, true, just something about concrete seems appealing to me. But in my wildest conceptualizing of DIY 3D printed cabinets, I figured a layer of sand with a layer of concrete outside that would be best - damping to prevent high frequencies from reaching the concrete, plus stiffness from the concrete to prevent any flexing, plus overall high transmission losses between the 5 layers (plastic, sand, plastic, concrete, plastic).
The LS60s and Blades are 3-way. Highs and mids go to the concentric driver (tweeter and midrange, respectively), and the lows go to the side firing woofers.
Well I would say "what about a 4 way crossover?" But I can't think of any DSP kits off the top of my head that do that.
I have a 4-way setup using a miniDSP Flex HTx. All DSP and amplification is done external to the speakers, with the exception of the subwoofer, which has its own plate amplifier.
Still, with the side-firing woofers in the cabinet, you probably could cross them over at around 250 - 300 Hz. A KEF concentric driver should have no issue handling the frequencies up from there.
Actually the idea was to have a constant flow pattern. Those woofers have a super low Vas (28L) and with two in parallel that brings it down to 14, but will still need cabinet volume in order to function properly. The holes would allow the energy to be dispersed throughout the enclosure. Proper dampening would cap it off.
I had the same thought. I wasn't sure how much extra space I needed for the subs so I left about 3 inches of play.
Nope, this is not an isobaric configuration, so you’ll need twice the volume for two woofers.
No, not in the setup that you have. You may be thinking of an isobaric design, which is different. https://en.wikipedia.org/wiki/Isobaric_loudspeaker
Be sure to model it in VituixCad. I suspect that you will need either larger holes or a lot more holes.
