"Everything HiFi is a compromise."
Amen brother!!
And I agree with you that 105 Hz is usually too high for something like a Swarm. I try to avoid letting the subs run up any higher than 80 Hz for exactly the reason you describe.
There is a technique that works in situations where the subs have to kick in fairly high. I had a customer whose 107 dB horn speakers shelved down significantly around 150 Hz, before rolling off at about 80 Hz. (His midbass horn was imo too small to hold up well down to the manufacturer's claimed 80 Hz low end.)
What we did was, use two amplifiers. We placed two of the Swarm units along the front wall near the main speakers, and those two units went up to about 130 Hz (which blended well with the downward-shelving of the mains at about 150 Hz). The other two Swarm units went on the side and back walls, and were rolled off above 60 Hz or so (blending well with the ballpark 80 Hz rolloff). The lowpass filters were all 4th order. It did take a little while to dial in all of the settings even with measurement equipment, but when we were done it worked well enough that he took out his checkbook. He was in a position to easily spend up to twenty times the price of the Swarm, so that was a nice outcome.
Duke
