While my input isn't about a sub,I do understand good low info at lesser volumes. Going from Merlin MM to Sophia; and changing nothing else---I get it.--Think Lou Reeds "Walk on the Wild Side" Tonal bass,indeed.
Lots of air= lots of subwoofer
After moving, my new listening space increased dramatically. My solo 10" sub just didn't do it. Now that I have moved up to two 15 inchers: the bass is truly being delivered. What I find especially satisfying, is not the heavy duty bass passages of recordings that really happen at high volumes, but the 4 string bass of a jazz quartet listening at very low volumes. The delicacy of prodigious bass at low volumes? I realize that is oxymoronish, but I think you understand what I'm trying to convey. Low volume bass (for instance, Missouri Skies) truly adds that gentle air movement that makes the music have another dimension; another feeling. Anybody with similar experiences? warren :-)