SVS PB-3000 vs PB-4000: Diminishing Returns or Night-and-Day Difference?
The SVS PB-3000 ($1,400) hits 17Hz at reference level in a 2,500 cubic foot room. The PB-4000 ($2,200) hits 15Hz and adds 3dB of headroom. That's an $800 difference for 2Hz and a bit more slam. Here's when the upgrade is worth it and when it's not.

