Kevin Patterson

tuning freaquency

Hey everyone i have a dual chamber box 1.4 cu. ft. in each chamber it is ported with a 3in. pvc pipe right now it is 8in. long i would like to know what this is tuned to i am planning to put an 90degree elbow and put another 8in. on the existing tube i would also like to know what this will be tuned to thenx in advance KEVIN

Kevin Patterson

Any one???

Rob Formica

It's a 6th order bandpass with equal chambers and identical tuning?

Wouldn't this create the theoretical situation where the sound from one port would be identical but 180o out of phase with the second port? I could understand the reason for wanting to retune the box as it must sound horrid?

Apart from the info you provided, you should post the T/S parameters of the driver if you want to get the actual port tuning.

Later...
Rob

*Shedding light by means of the combustion of snake oil* PC-ABX

Brian-K-Owens

Maybe he means it is dual chamber as in (2) woofers. . one woofer, one port in each chamber.

If so, it is tuned to 36-37 Hz (this assumes the 1.4 ft^3 is net volume after driver and port displacement). Adding another 8" tube + elbow will make it approximately 24-26 Hz (Have to guess a little, as I do not know the actual length through the elbow, how far the elbow slides onto the 8" pieces, etc.)

If it is a bandpass box, better get the t/s specs of the driver and design it correctly as stated above instead of just guessing on a port length. . .

here is a nice website that will help you in the port length calculations:

http://www.loudspeakers101.com/VentCal1.htm

Brian

Brian Owens

Kevin Patterson

Thanx for the replys no it is not banmd pass there 2 seperate chambers with there own ports and drivers