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pdtran
01-18-2007, 01:49 PM
Box specs:
24" w x 16" h x 19" d
Slot Port - 2 1/4" x 13 1/2" x 31" @ 45Hz
Port Vol - .65 cu.ft. ( included Port Wall Vol. )
Carpet Type - Charcoal Grey or Black
Round Terminal Cup w/ Spring Loaded Posts

I bought this from someone and he gave me the specs above. It says 45 hz is the tuning but when I was talking to DJ from audioque he said that the box was probably tuned somewhere around the lower 20s.

Anyone know how to calculate this?

Either way, I want to try to tune it to 38 hz is there anyway to do this?

jcbabb
01-18-2007, 02:03 PM
Looks like about 30Hz, using the car stereo.com port length calculator. Your net Vb is roughly just over 2cubes-ish, using your dimensions.

pdtran
01-18-2007, 02:09 PM
lol wow. that's kinda lame. how do u think cutting 10in. of port wall would do for me?

Immacomputer
01-18-2007, 02:15 PM
I got a net volume of about 3.5 cubes with a tuning of 25hz (possibly even lower if the port length given was just the length of the wood). Put a sub in there and see where it's tuned by using test tones.

pdtran
01-18-2007, 02:20 PM
how do i do that exactly.

the box is 2.5 cu. ft btw

skadude016
01-18-2007, 02:28 PM
you will find the round about area of tuning when you put it on some tones and where the woofer doesnt seem to be moving much at all. that is round about tuning

jcbabb
01-18-2007, 05:56 PM
Why is the slot port only 13.5" tall when the box is 16" tall? 16" minus top and bottom 3/4" leaves a 14.5" tall port. Using an inside height of 14.5", I do get the 2.5cubes of net Vb, and .6 cubes of port volume.

berserker
01-19-2007, 03:27 PM
Put a sub in there and see where it's tuned by using test tones.

how do i do that exactly.


Make a test CD from 15 to 35 Hz. Start going through the tones while gently holding your finger on the cone. Once you notice a significant reduction in movement, that’s it.

Death By Bass
01-19-2007, 03:43 PM
about 3.1cuft tuned to about 27Hz...