[gopies]

Hello
I am fortunate to have the p.audio bm-15cx38 coax's. The OB design recommended by the supplier has them at 24" wide, 29.5" height, with the driver 14.75" (mid point)
This is in 1" MDF (though recommended to be 3/4"). They are recessed.
However, in my ongoing reading, i think that the OB recommended to me may well not give the optimal performance.
Can someone recommend possible dimensions of the OB and positioning of the drivers?
I ahve loads more queries as well but wait for advice on this before I start embarking on other improvements with croosovers etc.
I am running a 2A3 SET to them.
many thanx
John

[Brad]

Hi John,

Welcome to Audiocircle!
I'm not familiar with that driver, but I'll take a look at it today...

The great thing about OB is you can try it several different ways until you find the combination
that works best with your room/equipment.

[scorpion]

Here is a link for a design which has been used for different size drivers: http://members.myactv.net/~je2a3/open.htm also 15", look at the japanese plans.

/Erling

[hurdy_gurdyman]

15cx38 coax

Thiele-Small Parameters
Resonant Frequency (Fs)    36 Hz
Impedance (Re)    7.0 ohms
Mechanical Q (Qms)    5.53
Electrical Factor(Qes)    .23
Total Q (Qts)    .22
Comp. Equivelant Vol. (Vas)    

10.13 ft3 / 287 Liters
Voice Coil Overhang (Xmax)    4.5 mm
Surface Area of Cone (Sd)    .083 m2
BL Factor (BL)    21.03 T-M


Judging from the T/S specs, this driver will never get enough bass on an open baffle without some serious eq.

Dave