Good hi-fi, home use, 12inch coaxials???

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I am starting to gather ideas for a new speaker system. I recently bought a pair of Kenwood LS-770 vintage speakers. They are fantastic!!!. They have a 10inch coaxial Fostex woofer and a 10inch passive radiator. I'm really loving the
sound stage of those!.
I would like to somewhat replicate those, in a larger format. I'd like foam surround, (high QTS) style, not pro PA speakers.
What i'm looking for seems rare enough?!.
Ideally a good old Tannoy driver would fit my bill i guess?.
Air suspension or, would mate it with a long throw 12 inch or a 15 passive...
 
I would suggest Beyma 8CX300Nd/N. One of the best coaxial drivers for hi-fi use. you would be surprised by the bottom end down to ~41-42hz in a ~40l BR box (it does simulate well bot will go that low in reality). the tweeter sounds smooth with polymer diaphragm all the way up to 18khz
 
Can I ask why PA drivers are out of question? Foam surround in general I don’t see much more, they typically rot/fall apart to dust over time. Some PA coax drivers have double paper surround and good xmax, and probably many variants of qts are you aiming for open baffle?

Poor response, high distortion. PA drivers are designed with different trade-offs. Typically very high power handling which means more mass that might be needed in a home, so larger VAS lower cutoff up top. A lit is given up for efficiency. PA speakers typically push the woofer way too high to reach a tweeter used way too low. So, a larger heavier tweeter giving far worse top end. Typically. A PA speaker is designed for vocals bandwidth, not violins.

Coax drivers seem attractive at first, but you are now talking about a waveguide tweeter ( yes more efficient) but the wave guide is moving and of course the response variations of the guide must be dealt with. They are consequently hard to do well.

Foam surrounds went out decades ago. They do not last.
 
I use a B&C 12" coax driver open baffle for 300Hz and up (a 12", big-ish Xmax driver handles 50-300Hz with some sealed subs below). The distortion and "moving waveguide" arguments are nonsense. Using the coax to only 300Hz the cone moves very little - much less than 1mm - even when playing very loud.

I will say that my main reservations about pro-audio coaxes are that the cone shape doesn't make for the finest waveguide and more importantly you don't really get to choose the CD (unless it's a screw-on type coax which has other problems).

So while I think the coax OB is pretty good, I think I'll be building something new soon (a sealed 2-way with a JBL 2217 mid-bass and a Radian 1" CD on a QSC 14"x10" waveguide which I'll run down to ~50Hz and stick with my sealed subs below that).
 
I've enjoyed some of Eminence's 12cx made for monitor use - magnets ranged 54oz/80oz/109oz. The 80oz magnet models had edge-wound voice coils. Unfortunately they are probably all custom ordered.

Regarding a light coned extended range 12 inch coax woofer and low mass tweeter, Beyma's "12cx" may fit that description. The woofer goes up quite a bit further than Eminence's Beta 12cx and its tweeter is much like the old Eminence APT50 but with data sheet indicating an aluminum diaphragm vs APT50's phenolic diaphragm.

Usspeaker apparently has some NOS

Beyma Coaxial Speakers - Beyma 12CXX coaxial speaker - Beyma 12CX 200 watt 12" coaxial speakers for all 2-way applications. Beyma 12CX coxial speaker and other Beyma 12" coaxial speakers here.

Here's the data sheet
https://www.beyma.de/fileadmin/seiten/download/pdf/Beyma_professional/12CX.pdf

Here's one of mine in a vintage Karlson "K12"
T22mKKc.jpg


WHrQf2k.jpg
 
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I'm following this thread with interest as I do have a coax itch to scratch. I've not followed the recent small Tannoys and realise that 4" units are way off the OT ask but seems between KEF and Tannoy there are some interesting products there. The Gold 8 active monitor is either rubbish or scary good value at around 400 a pair...
 
I picked up a pair of b-stock 15” Eminence coaxials that they manufactured specifically for DIY Sound Group (domestic use). I have yet to build an enclosure for them but when I measured their T/S parameters, I was taken aback not only at how well they agreed with each other but how close they both were to the factory specs. Very excited to hear them.

On axis frequency response:
15in-coax-in-room-average-png.935


On/off axis, 10° increments (ignore below 200Hz):
15in-coax-0-90-degrees-png.936
 
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