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Biohazard
12-10-2003, 02:56 AM
Hey guys,
i have a 15" XXX and i am making a box with 3.49 cubc feet and i was wondering if a 5.5x4x10 in^3 port, now i was wondering a few things...


is 35hz correct for this size port?
Does anyone know if 35hz is good for sql?more towads spl than sq though..u know what i mean?

Thanks guys!

LoneRanger
12-11-2003, 06:28 PM
Hey guys,
i have a 15" XXX and i am making a box with 3.49 cubc feet and i was wondering if a 5.5x4x10 in^3 port, now i was wondering a few things...


is 35hz correct for this size port?
Does anyone know if 35hz is good for sql?more towads spl than sq though..u know what i mean?

Thanks guys!

35 is what RE recommends for SQL, so of course it will be good.

5.5x4x10.125 is what i came up with. You're an 8th of an inch off :)

Biohazard
12-12-2003, 05:41 PM
yeah i actually got 9.94 with the formula but using winisd i got 10.125....weird.... thanks!

p.s. where did u see 35 is sql for RE?
what would be a little more spl?

LoneRanger
12-13-2003, 01:10 AM
yeah i actually got 9.94 with the formula but using winisd i got 10.125....weird.... thanks!

p.s. where did u see 35 is sql for RE?
what would be a little more spl?

did you remember to count the displacement of the port baffle itself when figuring the tuning by formula?

if not, i'd bet win isd did that for you and corrected accordingly :)

Tiny fractions of an inch or cubic inch can change the tuning by a hz or more, however, chances are you'd never know the difference.

Biohazard
12-13-2003, 02:55 AM
however, chances are you'd never know the difference.

thats what i figure...


would more spl be towards 30hz?

LoneRanger
12-13-2003, 03:37 AM
thats what i figure...


would more spl be towards 30hz?

higher tuning = peakier response = more spl

lower tuning = flatter response = more sq

finding a happy medium between the two = SQL

Biohazard
12-14-2003, 04:55 AM
higher tuning = peakier response = more spl

lower tuning = flatter response = more sq

finding a happy medium between the two = SQL
sweet :) i won $20 i was like 99% sure it went that way :) nice

anywho, thanks for the help, oh and if i were to fibreglass the front part of the box would this be very bad for the flex in the box? like would it still get loud or would it sound worse since i am pushing so much power through the xxx?

LoneRanger
12-14-2003, 10:59 AM
sweet :) i won $20 i was like 99% sure it went that way :) nice

anywho, thanks for the help, oh and if i were to fibreglass the front part of the box would this be very bad for the flex in the box? like would it still get loud or would it sound worse since i am pushing so much power through the xxx?

Fiberglass can be stronger than MDF if you use enough layers.