Alpair 12.2P Modeling Help


2009-01-19 8:40 pm
I'm not having any luck entering the driver parameters in my version of WIN ISD, was wondering if somebody could shoot some quick numbers for me.

Alpair 12.2P, Vented Cab, ~15L, single 6 sq in vent 1/2" long. Outside dimensions of the box are 9 1/2" W X 8 1/2" D X 15 3/4" H and 1/2" thick.

I was breaking in a pair of 12.2Ps and decided I'l mount them in a pair of old cabs I had, 2-way bookshelfs. I pulled the tweeter, that's the 6 sq in X 1/2" vent now.

Anyway, the things sound surprisingly awesome. A lot more bass than I would have imagined, and I don't run them very hard, I just want to see what the sim says about this.

Thanks, I'll see if I can get WIN ISD going in the meantime.
The volume will work fine (15.4 litre before bracing and driver).

Vent needs to be longer -- lengthened. Reponse as is is not very good.



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Bob Brines

2003-01-31 10:11 pm
I suppose that I am going to confuse you more but....

I just got my pair of A12P's yesterday and it may be a while until they are in cabinets , but I did some modeling anyway. 15L is the QB3 answer, but I think that a 20-30L EBS alignment might better utilize the driver's potential. It will get another 10Hz of bass. I am looking at a proper MLTL with an F3 ~ 40Hz.

For BR duties I quite like ~16 litres tuned to 50Hz - 55Hz. Works quite nicely with gain from a typical moderate sized British room, or a higher output impedance amp.


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Paid Member
2011-02-04 11:35 am
Shorter BLH for the A12P?

Recently had a chance to listen to Fostex 206EN drivers in the FE208 Sigma cab - must say I liked the sound. Powered by a 5 wpc tube amp the speakers sounded effortless, with very clear mids and clean bass. Read that Ron Clarke's Dallas is likely to be even better.

Wondering if a similar BLH (single front facing horn mouth) design can work for the A12P. Understand that Scott's Avebury is excellent, but at ~6ft, WAF is a challenge. Also room placement and distance from back wall can be a challenge in medium size rooms?