Do round ports have to be straight?

neonblack · Post by **neonblack** » Tue May 19, 2009 9:22 am

Can round ports be angled (90 degrees) so they can fit in an enclosure? Will this create different dynamics inside the enclosure than a straight port? I used a few programs to calculate a port diameter/length (for round port) for one JL Audio 10" 300W sub with 1 cu. ft. enclosure @ 31 Hz tuning frequency (per JL Audio manual) and the port length came out fairly long (16"-19") compared to enclosure dimensions (~16"x13"x9"). If I could use a port at a 90 degree bend it would work well.

NorthQuad · Post by **NorthQuad** » Tue May 19, 2009 9:40 am

I've seen U-shaped ports inside enclosures. I'm no expert but it sounded fine.

Ryan from Ohio · Post by **Ryan from Ohio** » Tue May 19, 2009 12:27 pm

Perfectly fine and normal.

Do it all the time with slot ports.

cargodz · Post by **cargodz** » Tue May 19, 2009 3:46 pm

In many cases you have to have a turn in the port to get to proper length for tuning... as long as it is secured well so it gets no vibration then you won't notice.

neonblack · Post by **neonblack** » Tue May 19, 2009 5:27 pm

Thanks for replies. Then my next question is: does it make a difference where the port opening inside the enclosure (depth) is located relative to the rear of the driver (behind the driver, in front of the magnet, 1/2 of depth of enclosure, etc.)?

cargodz · Post by **cargodz** » Wed May 20, 2009 4:56 am

The biggest issue is to make sure that the port is not obstructed by the sub(s), I try to keep the distance of at least 1 inch away from the back of the sub as many subs nowadays have vent poles on the back for cooling... Basically the same rules as applied for the back wall of the enclosure.

MobileAudio219 · Post by **MobileAudio219** » Wed May 20, 2009 8:19 am

Generally you're suppose to keep a ports diameter from any obstructions at the end of the port. So say if the ports 4" wide, keep obstructions 4" away.

Sorry if that doesn't make any sense, I don't have any.