"Am I mistaken, or do these subwoofer cabinet designs lack the ports that DJK had on some of his enclosures?"
The basic idea behind PPSL is the plenum with the push-pull mounted drivers. The box could be sealed, vented, 6th order vented (most of my designs are 6th order vented), or even dipole (the Linkwitz sub).
"What are the benefits of PPSL"
Distortion reduction.
When I built the first model PPSL over 20 years ago it sounded so different (compared to a 'normal' speaker) that I didn't realize what I was hearing (lack of distortion). It was only when I compared it with a large corner horn that I realized what was happening, that the PPSL was cleaner, less colored, and more musical.
"Cant find too much on PPSL... "
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PPSL djk About
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Push-pull Slot Loading (PPSL) sub drivers? [Text View] - AVS Forum
20 posts - 9 authors - Last post: Jan 4
Both SL and DJK are smart cookies. They chose this topology for very ... Maybe it would help if you explained how each would work in a PPSL? ...
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PPSL les hudson About
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High Efficiency Speaker Asylum
[IMGDEAD]http://usr.audioasylum.com/images/3/33876/100_1147.jpg[/IMGDEAD]
Just completed a new experiment Push-Pull double 15" subwoofer. This is the best sounding subwoofer that I've ever heard after building sub cabinets for 33 yrs. Love it. Les Hudson