Svs sub : should i go with sb13 ultra or pb 13

Sealed subs generally provide tighter (more highly damped) bass than ported models. You can check "group delay" specs at HTShack.com (if they're available for the models you're considering) and you'll see one measure of this characteristic. The trade-off is less true deep bass output per cubic foot of enclosure volume.

Most people prefer sealed subs for music, because you don't need a ton of clean output in the 20hz region for music (tho you might for cinema) and tighter bass is often (tho not always) a better match for high-end main speakers.

I have an SVS PB13 Ultra in black gloss with Casta Acoustic D8 floorstanding speakers and they blend perfectly. I run it at 80hz crossover and maybe 2 on the dial with all ports plugged. Just stunning. Mind you I had a $600 Hifi Pyon Mythology sub platform madeI for it because the little rubber feet did nothing for it. Now the pitch is perfect, tight and well tuned. I would go for either SVS. You can't go wrong. Good luck!

I had two SB-2000's and they hit low with those rumbly notes that seem to crawl around on the floor when you encounter them - but I never quite got them to integrate well with my Buchardt S400's.  I got a REL T/7i and quickly had it dialed in.  It doesn't rattle the walls or the dishes so you do lose that swampy bottom if that's what you look for.

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