Let me first of all say I am not a great fan of “pretty” home theater rooms, if you have the need, time and budget that is fine, but that is not what I was looking for nor did I want support for 3D. I wanted to put as much of my money, as I could, into the audio and video technology and acoustics of the room. Having my roots in both the professional music recording industry and secondly in broadcast video I wanted a room that gave me great audio performance for stereo and 5.1 audio with support for 2.4:1 video and 11.1 film sound.
Due to a complete remodel of my home, I had the opportunity to add “my own piece of heaven”. A dedicated music room that supported video. It had to meet many criteria, some of which were:
• Within budget – it was not elastic.
• Acoustically well controlled before the application of any electronic EQ.
• At least 60dB SRI to the main home, as I like it loud at night.
• NC level of 25dB or better with HVAC active.
• Flat RT of 0.2 secs. from at least 63Hz to 20KHz.
• No windows for total light control
• No secondary decay.
• Acoustically symmetrical for all audio modes; stereo, 5.1, 7.1, 9.1 and 11.1.
• Screen & projection system to support both 16:9 and 2.4:1 aspect ratios.
• Support vinyl playback.
• Seat three people.
• Technical systems to support:
o Separate safety ground from main house system.
o Isolated technical ground system.
o Balanced line levels to all active speakers.
o SD/HD SDI support for most hardware, I hate HDCP.
o Green pure sine wave UPS, only active upon power loss– not double conversion due to audible noise.
Well that was a start for now; I also had to deal with the realities of the various building code issues such as old underground pools, local streams and building lines that cut through where the room was to be built. These issues dictated the maximum room size if I was not to exceed the budget.
The room was to be part of the new renovation not a separate building. So it was designed as a fully isolated “box within a box” to reduce noise transmission and to have its own low velocity ducted HVAC system. The noisiest equipment, the projector, was to be installed inside the room, its NC rating was 27dB, but the room design supported its movement to an external placement if it became a noise intrusion.
The resulting available space provided for a room that had a finished size of 18’ 6” L x 12’ 8” W X 8’ H. These selected dimensions provide the most uniform spacing of all room modes and met a number (but not all) of well-known acoustics criteria. However, it restricted the placement of subs to either; two at the front 1/3 in from each side wall or four by adding one in each rear corner, (you will see why later). The other restriction that rapidly became apparent was that width speakers were never going to be possible so I deleted that requirement.
Although my goal was to design the room with acoustics similar to a recording studio control room, it was not practical/necessary to have the speakers raised above the floor as in a recording studio. This would have severally restricted the screen width and I did not want to use a perforated screen. Also due to space restrictions and access issues the door had to be almost in the center of a sidewall and the equipment rack needed to be located within the room on the same side as the door. This “rack room” was also to form a plenum chamber for 30% of the HVAC air entering the room besides cooling the equipment. The remainder of the air was fed through plenum chambers behind the front LHS/RHS speakers. The returns occurring from plenum chambers behind each of the larger rear surrounds.
So what equipment was to go into the room? I purposely chose the main five speakers to represent types that were frequently used in recording studios and cutting rooms and that had a THX PM3 rating. All the satellites needed to compliment and closely match their frequency response and power handling with the crossover frequencies to all HF units being the same. I already had a pair of subs that I liked and were a good match to the selected 11 satellite speaker system and had sufficient output to drive a 1900 cubic ft room. I say 11-satellite system, as there was to be two pairs of surrounds. The larger pair matched the front three for 5.1 music, the second smaller pair were for film surrounds. Each pair was appropriately positioned to meet their performance requirements.
A/V equipment List:
• 5 Genelec 1038’s for music and film
• 4 Genelec 8040’s for rear and side film surrounds
• 2 Genelec 8030’s for front heights
• 2 SVS PB12 NSD subs
• Audyssey XT 32 Sub EQ for primary sub equalization
• Denon AVP-A1HDCI with Audyssey XT32 upgrade + Pro kit.
• Denon DBP-A100 + SDI mod
• Denon DVD-3800BDCI + SDI mod
• Denon DVD-5900 + SDI mod
• Toshiba HD A35
• Thorens TD160S + Hadcock GH228 arm + Lentek Entre cartridge and head amp.
• iScan VP50 Pro with SDI
• BenQ W10000 with ISF calibration
• Panamorph UH380 lens with sled
• Da-Lite tensioned dual mask screen – 115” diagonal for 2.4:1.
So what did the room design end up looking like: see the attachment showing the various elevations.
In my next post I will review the room construction techniques selected, and why, and post some of the foundation, floor and framing pictures.
Pauls HT Room Model (1).pdf 166k .pdf file
Edited by Digione - 4/14/13 at 6:41am