If you can make an enclosure smaller and still "trick" the speaker into believing that it is in a larger enclosure by putting fibre fill into the enclosure, is there anyway or formula that it might be possible to trick a port into believing that it is bigger by "stuffing it" ? Just curious.

I haven't tried it (but was thinking about this very topic last week)..

My understanding is that you stuff the port to reduce the output from port, turning your enclosure into a 'semi-ported' box. You pick up some dynamics AND some extended low frequency extension.

They do work - this is how JL Audio won the subwoofer comparison about 6 years ago in Car Audio and Electronics - they sent in the best enclosure.

My plan to try this is build a moderately small vented enclosure, then start packing the port with rolled up dacron sheet in 2-inch sections.

^ Yep. That's the theory - sacrifice some output for more extension.

I have seen no formula though - it is trial and error.

i experimented with that with my ported doors, and had some good and some not so good results, it really is a trial and error situation

Peter Mitchell did this also with a Soundstream woofer in a comparo test quite a few years ago, He said the box was loudest wgen ported, best sounding with sealed (the test box Soundstream supplied was convertable). Then he put a pad over the port (not unlike an aperiodic design) and with a little experimentation got the best combination of SQ and output.

Wait a second...wouldn't stuffing the port prevent air flow and thus limit any benifits you get from a port???

I know there are some home theater subs that allow you to plug the ports to change the frequency response and output.

^ To re-iterate:

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