Cornwall "Ports"

[John Warren]

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On 4/8/2005 2:46:55 AM DrWho wrote:

A port is a device that actually reverses the phase of the rear wave (over a narrow band), thus preventing the cancellation from happening.

>>A port does not work this way. No phase reversals occur.

The air in the enclosure and the air in the port together, act as a spring and mass. They are a resonant system that can be tuned (Fb) to provide sound at a given frequency. The "spring" is the air in the enclosure and the "mass" is the air in the port.

The port "takes over" for the woofer at Fb. The port output and the woofer are in-phase at Fb although there is very little output from the woofer at Fb.

It's more complicated than that but that's the general idea.

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[IndyKlipschFan]

If you want to build a Corn-clone, stick to the master's design.

Keep em at the bottom...Like the pics...

Important.+++ Be sure when you do build the Vertical Cornwall, on the cut outs for the Woofer, MID, and HIGH....Horns are where they are supposed to be. It is different than if you just turned over a regular cornwall and flipped the mid and High Horns. I am sure Michael (ColterPhoto1) has a picture to share, but FYI it is not lined up top to bottom.++++++

http://forums.klipsch.com/idealbb/view.asp?topicID=60171&sessionID={5382F7B7-2DA6-4FC5-A109-F7B026E62FDF}

[Marvel]

And make a left and a right version too, so they are mirror images.

Marvel

[FlyingV]

Fr= Frequency (Hz)

AP= Area of Port

VB= Volume of Cabinet

VD= Volume of Port

LD= Length of Port