High Efficiency 15"/18" Drivers

bitzo wrote: is 2,7*10^-8 the conversion factor from cubic metre to cubic feet?

The complete equation returns "true" reference efficiency or "no".

www.carstereo.com/help/Articles.cfm?id=16

bitzo wrote: is 2,7*10^-8 the conversion factor from cubic metre to cubic feet?

no - it's just a constant

you have to change Vas into cu_ft before multiplying with fs^3

so

for PD1850:

2.7x10-8 (30^3 x 8.7933)
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0.22



=0.0291378

=2.91378x10-2 = reference efficiency

saul wrote:

bitzo wrote: is 2,7*10^-8 the conversion factor from cubic metre to cubic feet?

no - it's just a constant

you have to change Vas into cu_ft before multiplying with fs^3

....

I see... so to use directly liters

2.7x10-8 (fs^3 x vas x 3.5315x10-2 )
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qes

Hi All,

I am new to this site so please be patient!

I have 2 18"Fane XB reflexes and would like the addition of another two reflexes but; I would like a driver that is a bit more hard hitting. I am thinking about:

Void 1000 (New)
Void 1200 (Used)
P-Audio SD18-1700EL (New)
P-Audio P-Audio C18-600LF Mk2 1200
Fane SB (New)
PD1850 (Used)
PD186 (New)

I have chosen these drivers as they all have a voice coil larger than 4"

Plus I am on a tight budget.

Not too much technical terms as I have not got to grips with what all the Small Parameters means so, keeping it simple would be very much appreciated.

Thanks