After hours of moving stuff, calibrating, running tests, etc... I've got some results to share. I set up the tests reasonably scientifically, trying to isolate the variables in question: Floor construction and room volume. Due to laziness and not wanting to use my whole day, I limited the test to 3 rooms instead of the 4 I had planned on.The Procedure
- Level match Left, Right, Center, and LFE volumes using AVS Audio Test DVD
- Run Room EQ Wizard's sub volume calibration tone, adjusting AVR volume until I have 75 dB
- When practical, run a sweep in REW from 10 Hz to 200 Hz
- Try with futility to reduce dips in the graph by adjusting cross-over and phase.
- Watch scenes from Mr. & Mrs. Smith - rocket launcher and house explosion
- Watch scene from Wanted - 3.5 minutes in, lots of the heartbeat slow-mo, up until the mid-air giant gun shot.
- Generate opinion, ask girlfriend for hers
- Try another sub placement (only did this in the final room of the test)
- Dread moving my 80 lb. amp again
Ceilings are all 8 feetResults: Room 1 - Downstairs Living RoomSub Position:
- Downstairs living room (11 x 22) - Carpet over concrete, open
- Downstairs bedroom (11 x 15-ish) - Carpet over concrete, closed
- Upstairs living room (12 x 23, but open to kitchen making it 25 x 23) - Carpet over suspended wood, open
Front right corner, as pictured in first post of this threadFrequency Response:
Fairly good. There's a dip around 80 Hz and it's a bit rocky between 100 Hz and 130 Hz. An EQ could fix this response without too much effort, I think. Response was good down to 20 Hz, then drops about 5 dB to 16 Hz. Seems my sub can't keep up down low in this new room without EQ. Nothing bad enough to explain the missing mid-bass feeling, but a clue regarding the lower stuff.Movie Impressions:
These ratings are based on us actually "feeling" something, not the walls & furniture. A rating of "10" for me is the level of bass feeling I had in my old place (my great white whale).
Results: Room 2 - Downstairs BedroomSub Position:
- Vibrations - 3/10
- Shaking - 1/10
- Impact - 3/10
Front right corner, mimicked the speaker placements of the living roomFrequency Response:
Didn't run this test, since I had only moved the speakers and not the AVR. My cables I use for the FR plots just aren't long enough.Movie Impressions:
Results: Room 3 - Upstairs living roomSub Position #1:
- Vibrations - 4/10
- Shaking - 1/10
- Impact - 2/10
Front right corner, mimicked the speaker placements of the downstairs living room. For reference, the picture in the 1st post is roughly the same layout as the upstairs, just replace the bathroom/utilities with a kitchen near the stairs and bathroom near the bedrooms. The living room is open to the kitchen and foyer.Frequency Response:
Decent, I'd say. There was a dip at 100 Hz this time, and another one near 135 Hz. Overall pretty good down to 20 Hz, then falls off as it did downstairs. I did this plot down to 10 Hz and there's essentially nothing until 15 Hz. I'm really disappointed by the sub-20 Hz performance in this house. I think I have enough headroom I could EQ it flat to 16 Hz, but no lower.Movie Impressions:
Sub Position #2:
- Vibrations - 6/10
- Shaking - 4/10
- Impact - 4/10
Nearfield along right-side wall just behind couch.Frequency Response:
Didn't change much from the corner placement, surprisingly. The null at 100Hz raised a little, but still have the dip at 130 Hz. Again, strong performance to 20 Hz but drops off quickly.Movie Impressions:
Sub Position #3:
- Vibrations - 6/10
- Shaking - 4/10
- Impact - 5/10
Nearfield directly against back of couch (layed sub on its side, I think a SVS distributor said that was okay on this forum). Driver was on right side, port on left side, centered on couch.Frequency Response:
Didn't change much from the nearfield wall placement.Movie Impressions:
ConclusionsVerdict on Cement Floor vs Suspended Wood Floor:
- Vibrations - 8/10
- Shaking - 6/10
- Impact - 8/10
There was a noticeable difference in feeling the vibrations of low frequency bass on a suspended wood floor. Not life changing, but noticeable. It affect the feeling of "impact" a bit as well. The wood floor did help us feel immersed better into the action.Verdict on small closed room vs larger open room
Honestly I didn't notice much difference between the 2 basement rooms. I was really hoping the smaller room would let me feel more of the mid-bass punch, but it was about the same. One weird thing is that I had to turn up the speaker levels on my AVR to reach the same dB, despite the room being smaller.Verdict on nearfield placement
Nearfield touching the couch was the only way I achieved a high level of "feeling" in these tests. Moving it 6 inches away from the couch again removed 80% of the feeling.
I'm not sure if the nearfield placement reduces the audio quality or anything else, but I could feel the bass in my chest and back a lot more than the other tests today. It was rather close to having the sub in my old place about 4 feet from the listening position.What now?
I really prefer having the theater downstairs, so I'll be moving all my stuff back down there (I'm tired already just thinking about it). Nearfield placement worked out really well upstairs, so I'll be trying that downstairs now.
I'll definitely start looking into building a suspended floor as well, see how difficult/expensive that would be.
The FR plots also showed me my PC12-NSD just isn't digging that low in my house. Not as strongly as it used to at least. Perhaps I now have an excuse to build 2 end table subs
That'll give me the nearfield benefits, as well as allow me to dig deeper. My girlfriend wants a vibrating couch, so WAF is no issue
This is far from definitive of course, but hopefully you guys find this interesting. I can get some of the FR plots off my girlfriend's laptop if you guys wanted to see them.