Stacking subs


For years I’ve used a pair of Velodyne HGS-15s placed in the front corners. They are acoustically corrected by a bass manager and seem to integrate flawlessly with the KEF Reference 1s. In a recent post, auxinput suggested I replace the HGS-15s with HGS-10s for LF extension of the KEFs and use the HGS-15s with LFE from the Bryston SP3. That seems like a fine suggestion. I wonder about stacking the HGS-10s in the corners atop the HGS-15s, the easiest and neatest solution. Any thoughts or advice would be appreciated.
Ag insider logo xs@2xdbphd
Yeah, REL's idea of subwoofer line arrays is good, but that's not what dbphd is asking.

In my opinion, there might be a slight change in how the bass frequencies are affected by raising the HGS-10 about 20" off the floor.  You may get some reduction with some of the bass frequencies but improvement on others.  It's difficult to predict how the room would affect the standing waves.  You won't know until you try.
I wonder about stacking the HGS-10s in the corners atop the HGS-15s, the easiest and neatest solution.


oh i thought it was...  anyways, i will butt out, i have never needed to stack subs - so don't have any salient points to add
Another possibility is to use LFE from the SP3 with my third, as yet unused, HGS-15. In that case the sub would be on the side wall. The real advantage is that I wouldn’t need to mess with the current setup that sounds so good.

Previously I perceived the KEF Reference 1s to sound great with jazz and baroque, but less good for large orchestrations. But integrating them at 80 Hz with the HGS-15s changed that perception entirely. The setup does a Mahler symphony grandly.
Guys, hi
I am way more ignorant about subs than anyone here. BUT want to ask a related question. My speakers are low on bass but do (technically) reach down to 40Hz. Would I get better bass and a richer sound by adding one or two subwoofer? Running everything with a Lumin t2 to Hegel H390. Everything rocks except the bass...
Thanks.
Yes, especially adding two.  Some argue that high-passing your mains to relieve them of low frequencies handled by the subs duty will enhance their sound.
Do you XO the Kef’s bottom end with any bass management, like hipass in a receiver, if you do XO to the subs at what frequency 
I use a Velodyne SMS-1 bass manager that provides acoustic room correction, and low pass at 80 Hz with a 24 dB/octave slope. I’ve tried high-pass, but it seems to remove a sense of air. That may be peculiar to the Ayre zero feedback design of the preamp and amp between which the filter has been inserted.