Older Def tech Powerfield subs...

Im slightly.intrigued by these older, sealed designs....im sure they are fine for HT...but music?...any thoughts?
I owned a Powerfield sub. I don't remember it being sealed. I remember a slotted port.
PF15, PF1500, PF18 and PF1800 were all sealed. And yes, they did add a LOT of weight to movies, but they are most definitely not fast enough to blend with Thiel's or Magnepans (I've had/tried both). For a dedicated home theater, they are a very good, and inexpensive, choice, but for music, you can find better
I have a PF1800 (that is sealed) and it is far to slow to keep up with any high end speaker (which is why I mainly use a pair of JL Audio F113's which EASILY can keep up and blend nicely).

I remember the slotted port being on the back at the bottom. There are Internet pics showing this but apparently photos can be altered. The it's sealed' folks must be correct. Having owned one doesn't seem to matter.
Bottom line-there's better out there.
I had a Powerfield 15 and it was sealed.
Powerfield 1500 sub, sealed.
Powerfield 15TL sub, Slotted port.
TL = Transmission Line.
Thank you for the clarification.