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It seems the recent forum software move somehow wiped out my home theater room page in another thread that I referenced in my signature so I'm rebuilding it here.

MagnaTron 11.1.6 Home Theater Description & Photos of Build

I'll start with a description of some of the special features of the system and then show photos of the system including a few before/after photos. Most of the photos are thumbnails. Click on them for a larger view and/or slideshow.

Beyond 7.1.4 speakers using only 11-channel AVRs

The system currently uses two different methods from the "Beyond 7.1.4" thread to expand the speaker count beyond 7.1.4 to 11.1.6. I have plans to add a second subwoofer at some point as well (to even bass a bit more for the 2nd/3rd rows; the front row is fine) and a tensioned electric screen as well as a 4K projector eventually. It's currently a 2K/3D system with a 92" screen by DaLite. The system can easily be upgraded to full 11.1.6 discrete once a reasonably priced processor becomes available.

The two methods used to increase the speaker count using a standard 11.1 channel AVR are the so-called "Scatmos" method of using two Dolby Pro Logic processors (in this case Generation 1 processors) to extract a "center channel speaker" from to other signals, except instead of Left/Right -> Center, it uses Front Height Left + Rear Height Left -> Top Middle Left and the same for the right side with a second processor to create both Top Middle speakers, which get around the Disney "fixed print" 7.1.4 soundtrack limitation as well as the 11-channel count DTS:X limitation (before DTS:X Pro was released on higher count processors). This works very well and since my room is 24 feet long, it's needed to have smooth front to rear imaging across the entire 24 foot ceiling. Otherwise, I would have had to use in-ceiling or on-ceiling speakers at the 1/3 & 3/4 positions in the ceiling (aka "TOPS") locations to get smooth imaging with only 4 overhead speakers. That would have placed them in front of the 3rd row seat and barely behind the 2nd row seats and "TOPS" don't work with Auro-3D and effectively only used 1/2 the ceiling compared to "Heights" which typically start above the screen to the back of the room.

Matrixed Extraction Using Stereo Mixers

The 2nd method used to add Front Wide and Surround#1 speakers (the latter goes between side surround and rear surround) is basic matrixing using a powered 4-input stereo mixer that adds the signals together and creates a set of outputs halfway in-between at +3dB. Unlike "Scatmos," it does not remove the information from the input signals. This effectively creates a stereo "Array" effect whereby the phantom image appears half-way between the the existing phantom images from the original speakers and assuming you're sitting halfway in-between, they image normally, but offer a hard source for off-axis seats (in my room's case, this gets the surround signals to travel "around" the off-axis seats rather than in a straight line above them). It also widens the stereo soundstage in "stereo" mode as does another set of mixers I use to create a "dialog lift effect".

Dialog Lift Effect

The "dialog lift" effect uses a mixer to send some of the Left/Right and Center channel information to the front height speakers (how much is easily adjusted on the mixer). This lifts not only dialog to screen level (so the phantom image is in-between the center channel and front height speakers near the middle of the screen as if the speakers were actually behind the middle of the screen), but the left/right front soundstage as well, which then gently drops to ear level as it approaches the left/right front wide speakers. The combination of the two creates an extra set of delays that enhances the width and height of the image for stereo music sources and also acts as a partial "virtual line source" below 200Hz or so, negating most of the worst room interactions above and beyond the room correction system. The net effect for stereo is an image that sounds a bit more in character like my Carver Ribbon dipole speakers I have upstairs. The stereo image also sounds clearer than 2-channel mode, exactly the opposite of what some might think and not the slightest bit "muddy" since the delay is well within the time frame that the brain hears it as one signal.

The surround #1 speakers effectively bridge the 2nd/3rd rows with even hard image sources and smooth imaging and with older soundtracks, act like basic surround arrays so left/right sounds to the left/right of the row you're sitting in rather than from a single source (just as it would in a movie theater which all use arrays for basic 5.1/7.1 soundtracks).

New Layout Diagram and Speaker Angle Plot for the new system:

Home Theater Layout 11_1_6.jpg MagnaTronSpeakerAngles.jpg

Room Treatments:

-The room has a bookcase in the front with varied loading for diffraction and thick drapes behind the screen and equipment racks for darkness and absorption
-Thomas Kincade thick decorative tapestries are positioned at the 1st sidewall reflection to eliminate slap echo and dampen the first side wall reflection
-Left side has thick drapes positioned for both darkening the room at the side entrance and dampening with brick wall on other side for diffraction and varied reflection
-Room is non-symmetrical with half-bath helps break up standing waves with additional absorption placed in key corners.
-Huge rear drapes block rear exit and light and absorb rear wall reflections
-Various movie props and posters are placed all over the room for varied surface diffraction and reflection (mostly for decoration, however).
-Room is heavily carpeted with thick pad and 6 chairs around room

Overall effect is the room is quite dead (you can shout and it just disappears), but with varied delayed diffraction in various places to mix things up without making it look like a studio. Overall reponse is mostly within 2dB across most of the range with a few minor +/-4dB trouble spots. Bass is dead flat at the MLP, but a 2nd sub should smooth it out further for the 2nd/3rd rows (not terrible by any means as it is with only 1 subwoofer even)

AVR & Amps Used
The current AVR used is the Marantz 7012 with 11.1 processing with Dolby Atmos, DTS:X and Auro-3D support. It powers the mains, rear and side surround speakers (7 channels).

My older Yamaha 7.1 HTR-5960 AVR from 2006 is used in 7.1 Channel Input Mode to power the front & rear heights along with the front wides (6 channels).

A SMSL SA50 50Wx2 amp is used to power the Surround#1 speakers (2-channels)

The Onkyo Pro ES-600 Dolby Pro Logic Processor has built-in 65Wx2 channels that power the Side Height/Top Middle PSB S50 speakers

A Monoprice 4-in, 4-out Speaker Switch is used to select between Top Middle extracted output from the Onkyo processors or the Rear Height speakers, which can be used to send Auro-3D "Surround Height" to the Side Height speakers instead or in addition to the Rear Heights (parallel load). This can also be used to shrink the room down to 5.1.4 Atmos if desired as well along with the other added speakers to compare how it sounds anywhere from 2.0 to 11.1.6.


Sony PS4 (Games, Streaming and BD/3D playback capabilities)
Apple ATV 4K (2K/4K Streaming and Apps)
Zidoo X9S (3D movie playback from hard drive plus 2D Network streaming)
NVidia Shield Pro (KODI Playback from upstairs Mac Server with 10TB of storage)
LG 4K UHD Blu-Ray Player (2K/4K/3D Blu-Ray Disc playback)
Pioneer Laserdisc Player (It lets me play my old Laserdisc collection I still have)
Nintendo "Cube" (Plays older Nintendo games)

Equipment Racks Showing Above Sources and AVR/Amps:

NewLeftRack.jpg NewRightRack.jpg

Speakers Used

The system uses all PSB brand speakers except for the subwoofer, which is a DefTech PF-1500 15" subwoofer that gives the room flat bass response to 20Hz. The PSB speakers, despite being from a few different models, all share the same drivers in all locations except the rear speakers, which use slightly updated versions of the same drivers. This gives the room a perfectly even timbre and no sign of changes as the images move around the room.

(Note: All speakers crossed at 80Hz except rear towers until I get the 2nd sub)

Subwoofer = DefTech PF-1500 (20Hz-200Hz)
Left/Right/Center speakers = PSB Image T45 (35Hz-23kHz)
Front Heights = PSB B15 (55Hz-23kHz)
Front Wides = PSB B15
Side Surrounds = PSB B15
Surround#1 = PSB B15
Rear Speakers = PSB X1T (35Hz-23kHz)
Side Height/Top Middle = PSB S50 (Bipolar angled drivers mounted near ceiling so front faces 1st row and back faces rows 2/3)(55Hz-23kHz) Acts as 2 sets of monpoles.
Rear Height = PSB CS500 (essentially an Imagine xB in an enclosure)(55Hz-23kHz)

Def Tech Powerfield 1500 Subwoofer REW Response Graph (10Hz-200Hz):

DefTechFreq Response 20to200.jpg

Combined Subwoofer and T45 Right Channel REW measurement (mostly +/- 3dB across the line save a little dip and the cinema mode falloff above 10kHz). Note the subwoofer is turned up +3dB relative to the Main (purely preference for a little more kick in the bottom).

PSB Ref Right.jpg

Current 11.1.6 Home Theater Room (click on a thumbnail for slideshow 360 ordered snapshots). I've decorated with Movie Prop Replicas. Some of them may be out of date as I've been adding more items. There's a link in my signature to my movie props page and also to a photo of my 2-channel Active Crossover Carver Ribbon system upstairs):

Theater Room Front Left Screen s.jpg Theater Room Front Middle Screen s.jpg Theater Room Front Right Screen s.jpg Theater Room Mid Right Front s.jpg Theater Room Right Mid s.jpg Theater Room Rear Right Corner s.jpg Theater Room Rear Center s.jpg Theater Room Rear Left Corner s.jpg Theater Room Left Mid s.jpg

View of front row seating area and Table Stand with Cupholder and charging ports:

Seating consists of:
  • 3 lift chairs (narrower width with ability to raise chair height for viewing or to get out of chair for older viewers as well as full powered recline
  • 2 wider manual rocker recliners (extra cushy)
  • 1 Rocker/recliner with full powered head tilt and recline plus air bag powered massage and heat (that would be my chair at the MLP).
  • Wedge shaped table with 2 cup holders and place to put the remotes between MLP and right front center chair. There are coasters for all seats drinks as well.
Front Row and Table shown below (other chairs visible in photos above):

Theater Room Front Row s.jpg TableBack2.jpg

Original 6.1 Room Before Upgrades:

Powered by a 720P projector for many years back to 2007 until 2017, when the projector was updated to 2K/3D and the speakers and processors updated to 11.1.6 in 2018 with Dolby Atmos, DTS:X and Auro-3D. This was powered by the Yamaha 7.1 channel AVR, but it was analog out, so I had to use separate video switching as time went on and it didn't support anything discrete beyond DTS 6.1 ES. It did have 7.1 channel inputs which could use a newer TrueHD/DTS-HD decoder, which I utilized for a brief period while starting to move the home theater over and for testing.

Home Theater Photo Resized.jpg
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