The common used designations for sound reproduction with two or more loudspeakers are listed below:
ITU-R BS.775-3 Surround Sound Recommendations
The Radio-communication sector of the “International Telecommunication Union” developed a recommendation in ITU-R BS.775-3 for a multichannel stereophonic sound system with and without accompanying picture, updated in 2012 and will be discussed in excerpts:
- More surround channels are needed to broaden the sweet spot where all the listeners are able to perceive similar envelopment. An even number of more than two should be placed symmetrically at equal intervals
- The wide angular spacing between the left and right loudspeakers is required to achieve optimal sound reproduction.
- The base width (B) should stay within 2-3 m. Up to 5 m might be adequate with respect to the room design.
- In the case of more than two surround channels, the left and right surround signals (reduced in gain to avoid increased levels) should be directed to each of the rear side channels, respectively. De-correlated or delayed sounds might be necessary for reasons of interference effects, perceived envelopment, and de-localization. This can be implemented in state-of-the-art 7.1 channel sound processors.
In this post, we have reviewed the surround sound recommendations by ITU-R BS.775-3 and its considerations will be discussed in future posts. Items needed to improve sound and increase learning will be published in future posts. These will pave the way for creating a home theater of the highest quality.
The audio products offered in Saba intelligent systems, which include Dali speakers, Yamaha and Cambridge audio amplifiers, and inakustik cables with great variety and high quality, make it possible to implement any type of equipment to meet the relevant needs.