Talking about oldskool.... CERWIN VEGA S-15 free air woofers is what I used, 8 of them in my small opel kadett.
With a efficiency of 96Db and powered by 4 MS2125's they hit 156Db in 1996, good enough to win the European championship. [I still remember that day well

]
All day long I had beaten every competitor in every class [even the pro's with thousands of watts], and when it was him-or-me at the very last Db drag, I pushed the volume further than I ever dared.
After three seconds it was clear I had won; the crowd went nuts, I opened the door, expecting a burned smell... nothing! .

So for me, those subs were my favorite and some of them still run today in the install of one of my friends! [others played fine until the surrounds gave way].
Tried JBL GTI 15's as well; looked awesome, but did not play so well, and cones tend to rupture.
Another kind of oldskool woofers play in my home today; the 15 inch Klipsch La Scala's I play my music on, are build in 1968.
I replaced the woofers because the cones were sagged, but there is no difference in sound between the old [square magnet] ones and the new ones.
That's OLDSKOOL!
