Help with box design for Alpair 12P

GM,

The text file makes little sense to me, what are the basic dimensions.

dave

Hey Dave, hope your recovery is going as well as possible!

Not meant to per se, Hornresp needs to be loaded, text file Imported to view/save/modify.

Frankly, HR [freeware] has become the default program for so many here and around the net like WinISD, MJK's once was that I wish it was ~mandatory for folks wanting basic designs plus most pipe/horn types to at least view others speaker alignments/suggestions rather than having to [re]post various details.

All dims I.D.:

H = 106.7 cm
CSA = 280.32 cm^2
driver = 22.4 cm [0.21 offset]
vent = 90.48 cm [0.848 offset]
Av = 38.9 cm^2 [7 cm dia.]
Lv = 11 cm

That said, this is a design for someone else and after all these years, still can't quickly convert metric to Imperial, so didn't notice it being shorter [designed for super tweeter] than the norm [~38"/ 96.5 cm driver/floor] so will post it later.

GM
 
No. Coating the cone is not reversible.

i have been doing this on drivers since the late ‘70s and have had few fails (with more experience, none in the last decade or more).

It will reduce the self-noise of the paper cone, locking the surface fibres together in a matrix, but it is important to use as little as you can get away with or some top will be lost. And often people will thin the modPodge too much which can wrinkle some paper cones.

I have no trepeidation about doing it, and use the technique on almost all paper cones.

dave
 
I have done 2 pair of A12p, 2 pair of A12pw, and many, many more A10p. Coating 1st step in EnABLing them.

Jeff’s A12.2PeN (he as them in SuperPensils)

A122PeN-nat-wBlue.jpg


dave
 
A12p doesn’t really work that well in a reflex that large. Optimum is 15-20 litres. But the driver likes big boxes not only to produce bass but to get the most out of the midrange.

So a biggish ML-TL, TL, or horn is suggested. Pensil, Joan, Avebury for example.

dave

Please QC Greg. All dimensions rationalized to nearest mm.

dave

Although GM's ML-TL appears to be a very real-estate friendly design for I'd think a small'ish room. However, given what P-10 said WRT driver liking big boxes for bass and most out of mid-range, I fail to see the point of GM's design.
Can we get some more feedback on the intended use and how it worked out?
 
......didn't notice it being shorter [designed for super tweeter] than the norm [~38"/ 96.5 cm driver/floor] so will post it later.

Did some sims with 0.349, 0.424 offsets and once again, HR doesn't really like these type Vas, Fs, Qts ratios, so don't sim 'pretty' looking taller MLTLs due to large vents required just to get it 1.9 cm long unless heavily stuffed.

Re 'big boxes'; as I suspected, once passed Vas, didn't much see the point till I used the CSA of a Vas size cube, winding up with an early W.E./RCA alignment [vent considerably bigger than driver Sd], so at around 200 L gross, doubt anyone will build it even simple as it is, but even with < 3 W it sims mids - 40 Hz 'to die for' if the room's big enough to get it well away from corners and the driver can load such a big pipe, ~3.53x Sd vent. 😉 Otherwise can be DSP'd for increased dynamic headroom.

GM
 

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