Interesting....although I have sealed vs. the ported HSU subs. As I seek to integrate my new Mk2 ULS-15s, I'm asking myself the same question about what Q level to use, and EQ1 vs. EQ2. I've got a roughly 60/40 music vs. HT preference.
Right now I have two older ULS-15s without a Q control in 1/4 and 3/4 front wall placement, and based on experience I have the ULS trim on those units set to 16 Hz. I'm moving the two new HSUs up front, and given my own 2700 cubic SF room (20x15x9) I was going to start out with Q=0.3 to preserve maximal mid-bass headroom as per the HSU ULS-15 guide. However, I wonder what the tradeoff is between using EQ2 and Q=0.7 vs. EQ1 and Q=0.3. There's not a ton of room gain in this placement, but if I do corner loading I'm sure that would change.
My assumption was that as the most "capable" subs, I'd want to have the newer models up front rather than the older ones. However, I want to improve the 30 to 50 Hz bass, where I've got a null at 40 Hz I'm trying to get smooth out by additional subs and placement. I was planning to use my older HSUs in the back of the room to help with that, and use the ULS trim to try to dial them in for the < 50 Hz area. Or I can always get another Mk 2 or two and set it/them be more of a MBM LOL...but do I want to keep the existing Mk 1 where they are and using the new subs in the rear, since they've got more mid bass headroom than the Mk 1s? I'd be curious what you folks might think or Kevin_HSU if he's reading this.
In my system, unlike one with Audyssey XT32, I can control the boost/cut to avoid overboosting low frequencies by using the Frequency Limiter on my Trinnov Altitude's settings (I can turn off boost altogether below, say, 40 Hz if I wanted to and only cut lower frequencies). So I don't have quite the same issues that someone with a more automated room EQ might face.
Audio Gear: Trinnov Altitude 32 (24 channel), NAD M27 amps (3)
Video: JVC RS600, Seymour 100" UF Screen, Lumagen Radiance Pro 4444 (coming soon)
Speakers: PSB Imagine T3 LCR, Imagine T Wides/Side Surround 1, T2 Side Surrounds, Imagine XB rears, Image B6 screens, PSB CS1000 ceilings (6), HSU ULS-15 Mk 2 subs (4) - 13.4.6
HAA HT1 and HT2 Certification