Quad Subwoofers in real world living room

Hello all,

I wanted to share my experience using quad subs in a "typical" living room. I really got hooked on the idea when I heard Floyd Toole on the Home Theater Geeks podcast and subsequently bought his book. I had experienced good results when I went from a single sub to dual subs in room that was a nice rectangle at 14'x17'x7.5' that had 5' opening in the middle of one wall. This past summer I was lucky enough to have a new home built that wife and I really like with a open layout for the kitchen and living room area which is basically a very challenging room that many of us without a dedicated/sealed HT room are forced to deal with.





I decided to have the living room prewired for 9.4 for possible future expansion and picked up two more of my favorite subs. The quad energy S10.3's are currently located in the corners of the back of the room and L&R of the TV to the inside of the mains.





We can see that I'm dealing with a vaulted ceiling and opening to kitchen and beyond along with a opening to a hallway that rules out 4 corner sub placement.





I split the sub out from a Denon avr-1909 to a miniDSP 2x4 then to the quads unprocessed by the miniDSP for now. We see in this REW measurement that quad subs didn't perform a miracle but did help. There's still a null around 50Hz but not quite as bad.





I remember Mr. Toole on the podcast mentioning something about a subwoofer installed in the ceiling so it could be in the middle of the room and decided to measure a single sub in the middle of the living room and it really smoothed out the response much like I would expect it to in a sealed room.




Thanks everyone for looking at my unfinished quad sub experiment. I plan on doing more with miniDSP and REW in the future. Any comments, suggestions or questions are appreciated.

Thanks BeeMan,

I plan on posting more as I learn more and time goes by. I actually have a ton of REW measurements. After I measured a sub in the middle of the room, I told my wife I was putting one in the ceiling someday to her disapproval.

Thanks bsoko,

I really wanted the furniture out into the room, but my wife argues that it would be wasted space. I did take one subs and try it nearfield behind the MLP and it measured well but I found it reminded me of the old days of car audio subs booming. I found it to distracting and quickly gave up on it. I'm not unwilling to try it again though if I can get a good blend where it's not a distaction.

This mad me realize I don't think I tried the rear subs on the quarter lines on the wall, so I moved that couch real quick did a measurement with REW. The green line is with the rear subs in the corners and the couch against the wall, the purple line is with out from the wall a couple feet and the rear subs a little over 4' out of the corners along the rear wall.

I'm on a new gear diet for a bit, so I'll need to explore miniDSP first. But I would love to see some before and after measurements when you get yours BeeMan.

For my room placing the rear subs out from the corners on the quarter lines didn't seem to be a huge improvement, but I also measured a single sub behind the MLP on the center of the wall. The blue line shows the rear sub along with the two subs in the front of the room. The purple line is the response with the rear sub only. While it surprises me how effective this is giving the rooms open nature, I find the nearfield placement a little too distracting. I played a few scenes from INCEPTION and the tactile sensation of the gunshots was pretty fun but unnatural to me.

Hello all it wanted to share my most recent measurements I did today. My subs crossover to the mains at 80Hz, so the issues over that are not the subs fault.

This is my front left and right subs that are located on the 25% lines of the front wall. They neither alone or together have good response without EQ at my MLP.




Corner placement of the two subs on the back wall of the room measures much better at the MLP (yellow line), and the green line with all four subs going looks really good for no EQ in non-symmetrical living room.

Waterfall of quad subs at MLP. I previously noted that going from a single to dual subs truly made the bass omnidirectional the way that I didn't experience with a single sub. I'm finding as I watch more content (just watched PROMETHEUS and INCEPTION blurays) that it sounds like I don't have subs. What I mean is that to me in this space, the subs seem to actually disappear and the bass seems to come from any point in the room the other sounds appear to be from.

Thanks for responding Joe. Yeah, for me its all about how it sounds. Most people are surprised to hear that I don't like to listen at high volumes. I know you came from a sub background, please let me know if you have any suggestions for test to run or demo material.

Thanks ack_bk,

Five 15's should be very potent to say the least, best of luck on your DIY build. I noticed miniDSP emailed me about their new mic, and I'm very tempted. Please let me know if you get one. I've read very little about the Geddes method, I believe it's optimized for 3 subs as I recall. I'm using the radio shack digital spl meter with rew. It seems to do just fine for sub 1K measurements according to this info from Realtraps. Still it would be nice to measure higher with miniDSP mic, but of course it wouldn't apply to what I'm doing here.

Hi spyboy,

I'm quite sure you can shake your whole room with those subs. With all that great equipment, I think you owe it to yourself to give measuring your system a try... it's fun!

Thanks for the suggestion Mr. Seaton.

I believe I followed your instructions. I double checked that these were taken as they were last time with no eq at all, crossovers on the sub were bipassed, miniDSP is only acting as a splitter ect. The difference is that this is subs only where last time it's was the subs plus mains with a 80Hz crossover and my my tripod is on the couch in the MLP, but I do no guarantee that it is dead on to where it was last time and we know if I was in a lab environment that would be cause for a beating.

This is a bit hard to read, please let me know if you would like me to separate them.




This is my graph format from last week for reference.





Thanks so much for your help, I'm off to meet up with bsoko2, I hope he takes it easy easy on me with those quad Submersive HP subs.