I am not having much luck digging up anything on my own, much less something I can actually still buy from Harman.

I have some PT800 satellites and am looking to make a pair of DIY subs to substitute for the PS1400's. They may be used as conventional subs but I would like the appearance to line up just in case I want to use a docked arrangement as was originally intended.

I need more HT-ish performance than the LE14H-3 / PS1400 can provide, not to mention the cost issues and burden of trying to find them.

I believe a pair of L8400P's would be almost perfect for my wants but the cost is high - I'm not particularly fond of JBL's plate amplifiers and think I have a very good chance of getting better results out of the same ~$1,200-$1800 cost of two new L8400P's.

I tried contacting Harman about the 12" L8400P woofer but it is not available. I believe I would be happy with that and the looks would work out well, but it is not available so there you go.

There are some GREAT pictures of SUB1500 DIY boxes built for the exact same purpose as me... but that driver is also long past available.

So, I'm now looking for suggestions. Any ideas? Limited to ~3 cu ft boxes.