Subwoofer sugestions for ProAc 1sc

I'm looking for suggestions as to a good match for ProAc 1sc's. I would prefer feeback from past or present 1sc owners or people who have experience with the 1sc. My feeling is that the synergy between main speakers and Sub is of upmost importance. Thi is in the context of a 2 channel system please.

Thanks in advance!
Conventional wisdom would suggest REL Strata III or Strata 5 should work well with the 1 SC's, especially for music. I think they are worth a listen, but try to have the audition at home/in your system, just to be sure.

I had a REL Strata II that didn't work well with my Proac 1 SC's, and I am happy with a Sunfire True Sub Mark II replacement. Maybe it was a room effect that affected my REL's sound. (I have an unusual configuration for this system in a sunroom.)
Ahh, Pepler another good thread you've started.

As you know I own both the ProAc 1SC and Tablette 50 Signature. For the last three+ years I've used them with an NHT SW3P and matching SA3 mono sub amp, later upgrading to a Bryston 4b with a Paradigm X30 crossover.

I didn't realize how poor the NHT was with EITHER amp until I bought my ProAc 2.5s early this year. While the 1SC+sub combo delivered more depth it completely lacked the tone and articulation of the 2.5s.

I am however contemplating a sub upgrade that would be used with the 2.5s and also my home theater. I've narrowed my search down to the REL Stadium III and Velodyne DD-12. I'm leaning towards one of these new Digital Drive subs from Velodyne, because they are so versatile and the testimonials so far have been glowing.
I realise this is an old thread, but I would like to suggest ProAcs own ER one subwoofer. 10" downfiring sub that is very easy to use. Hf connection is Nuetrik and line level for Lf, both with separate levels. Sound is superb music and movies.