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<blockquote data-quote="Papermaker85" data-source="post: 8475871" data-attributes="member: 572595">i agree but to an extent. that sounds good in theory because it does lower the peak yess but you loose even more efficeny from the lack of damping. ive built about a dozen w7 boxes 1.75 is stil peaky and bottom heavy and still falls off fast above 60hz. instead you go slightly smaller to increase the efficiency above tuning(while a larger box increases efficiency at and below tuning) and you increase port are which also changes the damping(qt)s and lowers the acoustic resistance around and at tuning.. this does 3 things. lowers the group delay between the driver and the port, shifts the effective bandwidth OF the woofer higher and increasing port area decreases the QT of the port making the ports bandwidth more efficient and effective and have a narrower bandwidth at tuning so you get greater efficiency at tuning despite the smaller box while keeping group delay lower..think about increasing port area like lowering your QES/QTS ad tuning the port like the subs compliance. its peakier ove a narrower bandwidth.the smaller box also shifts the phase and impedance lower this is more affetive for high frequency output becasue that high above tuning the sub is doing above 80% the work where as in the port at tuning does all the work and the sub barley moves..</blockquote>

[QUOTE="Papermaker85, post: 8475871, member: 572595"] i agree but to an extent. that sounds good in theory because it does lower the peak yess but you loose even more efficeny from the lack of damping. ive built about a dozen w7 boxes 1.75 is stil peaky and bottom heavy and still falls off fast above 60hz. instead you go slightly smaller to increase the efficiency above tuning(while a larger box increases efficiency at and below tuning) and you increase port are which also changes the damping(qt)s and lowers the acoustic resistance around and at tuning.. this does 3 things. lowers the group delay between the driver and the port, shifts the effective bandwidth OF the woofer higher and increasing port area decreases the QT of the port making the ports bandwidth more efficient and effective and have a narrower bandwidth at tuning so you get greater efficiency at tuning despite the smaller box while keeping group delay lower.. think about increasing port area like lowering your QES/QTS ad tuning the port like the subs compliance. its peakier ove a narrower bandwidth. the smaller box also shifts the phase and impedance lower this is more affetive for high frequency output becasue that high above tuning the sub is doing above 80% the work where as in the port at tuning does all the work and the sub barley moves.. [/QUOTE]

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