Building a Moderately Priced HT - Speaker Placement Diagram
Loudspeaker layout should be a simple process as long as you understand a few basic principles. While there are a myriad of options, the principles of good loudspeaker positioning are relatively constant for home theater. Unlike some, who recommend full range speakers placed in a near-field configuration around a single listening position, Audioholics' stance is more of an "every seat is a good seat" approach. It does no good, in our opinion, if a home theater has a single "golden seat" and your guests (or significant other) are sitting in a bass mode or in a place where the surrounds become distracting and the soundstage is collapsed. As a result, we recommend dipole or similarly diffuse speakers for the side surrounds and careful subwoofer placement to alleviate the effects of the room's natural standing waves (bass modes). Please see our article on subwoofer placement guidelines for an expanded view on this topic. When possible, three matched speakers for the front soundstage are best (with a "behind the screen" center channel being a good way to accomplish this) but we recognize, as in the case of the RBH Sound CinemaSITE, that there are necessary exceptions and alternatives that may employ a different center channel. In these cases, we simply recommend (though insist would be more appropriate) that the center channel be very compatible with horizontal placement with careful consideration given to correct horizontal and vertical dispersion as well as timbre matching the main speakers.
The final complement of loudspeakers which had to be configured into Reference System 2 included:
- RBH Sound Signature SI-6100 for front and center speakers (located within the CinemaSITE enclosure)
- RBH Sound Signature SI-1010P subwoofers (located within the CinemaSITE enclosure) powered by dual SA400 amplifiers
- RBH Sound Signature 66-SE hybrid surround loudspeakers (in-phase midrange drivers with dipole configured tweeters)
- RBH Sound Signature 41-SE surround back speakers
Additional loudspeakers can be used within the reference system through redundant speaker connections which were placed in strategic areas throughout the room. We did this to better facilitate testing and bringing manufacturers' products into the room without having to completely disassemble the RBH Sound CInemaSITE.
Identify Compromises and Design Constraints
Unless you are designing and building from the ground up you will likely have to identify, preferably early on in the process, particular design constraints associated with the home theater project. For some this will include issues such as ceiling height, doors & windows, compounding room modes, construction materials and budget limitations. With Reference System 2, the largest constraint was its intended "dual-use" configuration. While a dedicated home theater is typically the best solution, I wanted to be able to co-exist within RS2 and conduct measurements, write reviews and perform all of the functions associated with evaluating consumer electronics equipment. It not only made ergonomic sense, but the net result is that I can co-exist with the equipment I am evaluating and writing about.
Attempting to allow both uses to share the room space brought up some interesting issues and challenges, including the following:
- Additional networking and power requirements were needed in a second room location
- The listening positions had to be moved forward slightly to accommodate a desk
- A second row of seats was impossible
- Seated distance to the screen was decreased, resulting in a potential issue for lower resolution projectors (a minimum requirement for any projector was acceptable resolution with a screen width that was 1.5x the seating distance).
- Rear closet doors mandated a slightly higher-than-normal mounting position for the surround back speakers.
- A mandatory in-room projector location required a very quiet projector so as to not allow noise to distract from the viewing experience.
- A whole lot more cabling was going to be required to make everything run smoothly (we turned to Impact Acoustics to help us with this particular aspect of the room)
In addition to these constraints, we imposed some additional considerations when selecting the RBH Sound CinemaSITE as our reference loudspeaker system:
- The twin SI-1010P subwoofers are in fixed locations, resulting in the inability to use subwoofer placement to reduce the effect of room modes/standing waves
- A behind-the-screen center channel was not yet possible so we needed to utilize a below-the-screen center channel specially configured for that system and correctly aimed towards the listening position.
As you'll see, these design constraints were more than tolerable and we utilized a combination of speaker placement, speaker aiming, phase adjustment and EQ to correct for any anomalies caused by our particular scenario.