View Full Version : Port Length

10-05-2005, 04:36 AM
I need some help with my port. I am putting a 15" rockford in my trunk. I am planning to put a 4" port but i don't know how long the port should be.

Any ideas?

10-05-2005, 06:54 AM
well there is a few things that have to be taken into consideration when calculating your port length, then just your sub diameter.

like what is the box internal volume. " external dimensions minus wood walls thickness""minus the port and subwoofer displacement".

what is the tuning freq of this box. "selected by experimenting with different port length, diameters and enclosure volumes, and how well the sub responds in those specific enclosure volume, with that port length and port width."

note: keeping in mind that certain port diameter in combination with xmax of the sub, and the power being sent to the sub, can cause, port noise that if at the usable freq of the enclosure could be annoying as hell. so always use the widest port opening with a light that fits in you box if port is internal. or just install it externally, or partially external.