[benguin]

The 15" Salk Rythmik does come with the 600 plate amp.  The standard dimensions for that one are 19.5"w x 24"deep x 27.5h with spikes.  Given that these are custom cabinets, you could likely play around to get a size that works for your space.

If I recall, these enclosures have quite a few differences from the standard Rythmik boxes as well.  Plus, you know you'll be getting a top notch finish.  I'm looking forward to trying mine out.

[msommers]

^^Saw your post on AVS about deciding to go with the SS8 from the STSC. Certainly has got me thinking about just biting the bullet because the size of these subwoofers are a lot bigger than I was expecting, and the depth is actually a bit smaller than the HT2. Two towers is a lot cleaner and I'd never have to worry about upgrading because the SS10-12 are just not my style in terms of shape and size, no matter how awesome they sound.

Here's a post I made with the dimensions of my SongSub:
http://www.audiocircle.com/index.php?topic=94452.msg943135#msg943135

And here's a post Jim made about positioning (although it doesn't exactly address your specific question):
http://www.audiocircle.com/index.php?topic=97241.msg975167#msg975167

As far as my impressions: I've never regretted getting it, but I also don't have nearly the experience of others here and have no idea how it would compare to a Rythmik sub. Ask questions if you have them, though 

Thanks for the link, those speakers are gorgeous! I too am looking at using rosewood and I'm really digging those gold plates instead of the silver ones. Might go for gold spikes as well to match.

Just need to audition some Salks because I'm really wanting them to work out.