Is it ok to plug the port on my woofers?

I wouldn’t suggest doing this. See the port is there to allow the speaker to move freely. Plugging that port would make the speaker act as a plunger so to speak and cause stress due to the compression of the air. If you do this, don’t expect your speakers to last very long.

Depends on the quality of the speaker – some are reinforced for this kind of thing – others will rip in very little time.

The cones are made of aluminum and connected by fairly thick rubber.

Ports are there for a reason and one of them is to allow air to move in an out of the speaker. These speakers sound beefy having 15” woofers and woofers magnets and coils can get hot especially the big heavy magnets of large diameter woofers at high volumes. So I would open the ports when you are cranking the volume to avoid having to re-cone those speakers.

here is a pic (referring to the two center speakers)
the ports on on the top

http://www.facebook.com/photo.php?pid=179068&l=0db4114a78&id=173646205

No. The drivers – the electromagnetic elements of the speakers – are specifically designed for vented enclosures. Drivers that are designed for sealed enclosures have different power demands (higher) and mechanical characteristics. The cones are constructed differently to use the internal air pressure as a return spring.

Most speaker systems are ported these days. You can drive them with less power because of the acoustic cancellation of the back wave. A sealed enclosure does it with containment. However, it’s hard to design a ported enclosure that sounds really good. The best high-end speakers still use sealed enclosures for this reason.

You get the best results from a ported enclosure by placing it in a corner, and it will perform best in an acoustically dead room – one with carpeting, drapes, and padded furniture.

@IchtheosaurusRex Thank you! That really helps me out!