@mofojo
Since my first pair is balanced force 12” subs, I was leaning towards the Rythmik G22, which is also a 12” balanced force sub. I’ve heard many say that they mix and match subs without any untoward effect. I’m almost more curious to pair with a different brand to either validate or determine if my experience is different.
@gemoody
The crossover would be quite dependent on your own speakers. I have full range electrostats, and currently prefer the LPF set at 55 Hz, although I’ve tried everything from 25 to 55. I do keep the volume rather low, set at 35% of max volume, but I suppose that’s highly dependent on size of the sub, how many subs, and size of room, amongst many other variables.