Forward facing ports, you probably couldn't measure any differences in comparison from one style to the next. I almost always use round ports for build simplicity. I've used 2226's of and on since 1978 when they were early generation 2205's in pro DJ systems.I always like to see guys use them in HiFi builds. Have a 2226H in my small studio system, soon to be a pair. They are a great sounding driver and can take a pounding. They have an old school punchy sound to them, very nice detail and are fairly transparent. I can listen to them for hours and not fatigue.JBL's current style for the more compact subwoofers in the professional line is triangular ports in the bottom corners. I suspect that is more for packaging more than any sonic aspects The pro subwoofer I am referring to is the JBL ASB7118. I bought one at a clearance discount rate to clone the cabinet essentially. I decided to just keep it as a single sub for smaller applications with a single sub and picked up more 2269H's for use in the "cloned" cabinets in multiples for larger systems.For your cabinet damping, it will only take lining the inside walls.To run one out to 1Khz won't be a problem, they are rated to 1200Hz and can go higher for specific applications. For your question about band pass. All speaking enclosures are band pass, simply from the mechanical limits on the drivers for frequency range. No, they are not band pass like a purposely designed bandpass subwoofer design. For a ported design, which is a Hemholtz Resonator, the port becomes acoustically invisible above 150Hz and only reinforces the front wave of the driver below 150Hz. The upper end performance is simply that of a forward facing direct radiator driver.Cheers