Best Of

I don't think it would be the best match with the 1.7i speakers.

In a large room Rel would only recommend a single S510 or dual T9x with the 1.7i speakers for music. The S812 I have is considerably more powerful than the S510s I have and easily overwhelms the main speakers. As a consequence I only run it at about 1/4 power to blend in with a pair of L800s which produce way more bass than the 1.7i speakers. The best matching of subwoofer(s) to main speakers is what's critical.

For a 3D system for home theater Rel recommends dual T9x matched and balanced to the 1.7i mains, and dual HT1205 MKII for home theater bass with one placed at the rear of the system and one anchoring the center speaker.

You are more likely to hear one sub in mono versus 2 in stereo IME. Also, keeping the sub that low is somewhat normal for a 2 channel system. Otherwise, they can quickly overpower the mains, knock the balance off and overloading the room quickly.

FWIW, both my Rythmik subs are running at probably 14 to 15%. That's plenty enough to be well balanced to the mains and both to the room.

One further thought. The larger the sub and the lower it hits, the harder it gets to integrate to both the mains and the room.

What do you feel that you are missing with your current subs?

Tom