Alpair 11MS close-listening (nearfield) project

I realised that I forgot to add any progress to this enclosure build. There isn't really a lot to it, just the front part mentioned previously had some holes drilled and nuts glued to the rear of the baffle, to provide mounting for the driver, and was then joined to a full bowl for the rear.
joined-bowl-01.jpg


This was done by bending a metal strip into a hoop. It was bonded in place using JB-weld epoxy; the hoop was snug enough that the two halves would stay firmly together even before the adhesive was used, so I don't believe there is a lot of demand placed on the bond.
joined-bowl-02.jpg

I stuck some self-adhesive bitumen on the inside, though it probably didn't need it as the assembled bowls don't ring like the open/half bowls do. Then a layer of felt and then filled with hollow fiber stuffing

That got things far enough for some initial tests, which (with the use of rough and ready eq) were quite encouraging. However I haven't got to the point of proper measurements and eq curves, partly because the music laptop broke: my time has instead been going into reconfiguring a PC... which means there is now a desk involved. So i might abandon the spherical idea as somewhat larger (and more conventional) rectangular boxes would now make more sense.

It would also offer the possibility of adding a woofer in WAW configuration. I'm really impressed by the 11MS wide-band/full-range approach (at least for close listening), and this is my first venture into it, there is a clarity to things that I haven't heard before and seems quite special. But am less impressed by the low end or the repercussions of using heavy EQ to compensate (in such small enclosures). So adding a decent woofer (or perhaps a small one and a separate subwoofer) might be the way to go. And /Or I could cut away the back corners of the desk to allow taller tower cabinets. Many more possibilities for achieving a better lower end than the somewhat restrictive small spheres permitted.
 
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Just to add some closing notes to this older thread: I did go on to start a different project instead - involving a small woofer (as a WAW). For near-field listening at modest spl and with the need for low bass removed it therefore made much more sense to use a smaller widerange driver instead of the 11MS, so I went with the alpair 5.3 and initial testing is most encouraging; I have very high hopes of this one.

For a project with bigger (room) speakers I have just now re-tried the 11MS as mid-tweeter and have again found much to like. Yet they still don't quite have the top end I wanted. So for me personally, I think these drivers would be at their best if you truly need a loud-ish full-range driver in a modestly sized box; but if you can go to a WAW (or maybe full-range in a big TL or similar) then IMO a slightly smaller FR driver might be optimum.

That said, I suspect the 11MS might also have most potential as a wide-range main/mid driver that is both woofer and tweeter assisted. This 3-way strays even further from true full-range use than a 2-way WAW, so might not be a subject for the full-range forum. But i think it is a potentially a very interesting use of a mid-sized wide-range driver with the benefits of mono-suspension.
 
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Thanks Allen. I did play around with a software equaliser; it could (of course) boost the upper end but things didn't sound very realistic compared to a tweeter; still a little dull (even if louder) rather than light and airy if that description makes any sense.

However, it was quite a crude thing (just seven sliders) and so I suppose may or may not do a very good job. So your point is a very good one, and something I should try more carefully; having a PC source (in my case Linux-based) means I could try all sorts of different things. I shall have a go this evening. It would be good if equalisation or DSP etc could compensate convincingly, as they seem nice drivers otherwise.

Cheers,
Kev