"I highly recommend purchasing Hsu products"
Have you listened to Hsu products? I haven’t - only my existing single REL R-328, which sounds great for me.
But I’m upgrading - below are the candidates. Pricing is per sub if purchasing dual (SVS will -$100 from the 2x total). REL is not on the list: they’re over-priced compared to these competitors, of which the PSA’s are the priciest.
The HSU and PSA models use paper drivers, not aluminum. Does it matter, objectively? I don’t know.
The Rythmik and HSU models appear to support speaker-level line in. Comparable to REL’s fancy-pants Neutrik connection? Maybe.
sub | $$$ | driver | amp | freq. | size | spkr-level input?
Rythmix F12 | $893 free ship | 12" aluminum | 370w rms class A/B servo | 14-100Hz ±2dB | 15.75x15.75x17, 62lbs | yes
Rythmix F12-300 | $700 free ship | 12" aluminum | 300w rms Hypex servo amp | 14-100Hz ±3dB | 15.75x15.75x17, 57lbs | yes
SVS SB-3000 | $999 free ship | 13" aluminum | 800w rms class D | 18-270Hz ±3dB | 15.6x15.2x17.8 | 54.5lbs | no
HSU ULS-15 MKII | $779 + shipping | 15" paper | 600w rms class D | 20-200Hz, ±1dB | 18x18x18, 65lbs | yes
PSA S1510 | $1,300 | 15" paper | 960w rms class D | 19-200Hz
±3 dB | 17x17.25x18, 63lbs | ???