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3pis built & subs purchased. Finalizing Placement in AT Baffle Wall
Wayne: Thanks again for all of your feedback and expertise. Only one of the JBL 4641 subs shipped, and it arrived damaged. B&H was kind enough to cancel the 2nd JBL and arrange for return of the damaged one for a full refund. This left a hole in my HT LFE, and several AVS forum conversations later I have pulled the trigger on two GSG BTS flatpacks that will utilize 21" LaVoce SAN214.50 pro drives. Attached are my revised floorplan and baffle wall POC. Any thoughts on how these subs may (or may not) play well in the sandbox with the 3pis? I know I probably should have asked *before* I made the purchase, but they are at least 2 weeks out on shipping, so if there are any glaring mismatches, I'm sure I could always edit these choices. Thanks in advance for your feedback.
Re: 3pis built & subs purchased. Finalizing Placement in AT Baffle Wall
It looks great to me. At first glance, I thought maybe the mains could have been higher in relation to the flanking subs but when I started looking at actual dimension figures, it all looks right to me. Should work very nicely.
Wayne - You mentioned that the subs should be next to and slightly below and in front or behind the L/R channels. I am getting ready to build the baffle wall, and see that it would be easier to build if have the subs slightly above rather than slightly below the L/R channels. Would this have the same affect? How would having the subs slightly above the mains affect the listening experience? -Jon
That will probably work just fine. Do set it all up on stands and audition it before committing though. One of the things required for flanking subs to work is an unusually high frequency low-pass on the subs. This provides blending in the upper midbass and lower midrange where you get SBIR from the wall behind the mains. The blending smooths the deep notch created by the resulting self-interference. But the subs must not be loud enough to be localizable, and the main frequency range where that can occur is the blended region between around 80Hz to 150Hz. So set it all up and dial it in. Listen to vocals, cello and piano. Make sure it all sounds like it is coming from a single source, and that you cannot detect the subs. They should blend seamlessly. You should only know you even have subs by the presence of deepest bass, and even that should sound like it came from a single source in front of you.
My plans have been updated. Everything is purchased except subwoofer amps. Some have questioned my use of different brand speakers for the mains, surrounds, and Atmos. I wonder if anyone here has any insight as to how the surrounds and height speakers I have purchased will sound (timbre matching) compared to the 3pi LCRs based on their reputation, construction methods, and materials used. Except for the subs, everything is being driven by three Starke AD4.320 4 Channel Amps. They do 225W/channel into 8ohm, or 320W/channel into 4ohm. The center channel 3pi will get two channels bridged into 300W. LCRs = 3pi x3 w/ B&C Drivers Side & Rear Surrounds: Starke AX65 x 4 200W RMS @ 4ohm 90dB Sensitivity w 2.83V/1m Frequency Response: 55Hz - 22kHz Max SPL @ 1m = 112dB Single 1" Titanium Tweeter Dual 6.5" Ceramic mid/bass drivers X.X.4 Atmos Height Speakers: Klipsch PRO-180RPC LCR x 4 50W RMS @ 8ohm 96dB Sensitivity w 1W/1m Subwoofers: Full Marty by GSG Audio x 2 Driver: B&C 21DS115-4 1,700W @ 4ohm 99dB Sensitivity @ 2.83V/1m