For that, you need to use each of the secondary AVR’s Left/Center/Right tones. The primary AVR should send tones to all 7 ground speakers and 4 of the heights (Top Front and Top Rear), but it cannot check the Top Middles. Preliminary CalibrationĪfter spending a very long time hooking everything up, you can use each receiver’s internal test tones to validate that all the speakers are working. This is the same method by which ProLogic II in a traditional 5.1 system can pull movie dialogue from a stereo soundtrack to form a center channel. Each downstream AVR receives what it believes to be a stereo signal (actually comprised of one part Top Front and one part Top Rear), and then uses Dolby ProLogic II to extract a center channel between them from any mono sound information common to both. In Part 1 of this article, I explained the concept behind using two additional A/V receivers in the downstream signal chain to derive new Top Middle speaker positions between the Top Front and Top Rear channels that the primary Atmos/DTS:X receiver decodes from a Blu-ray disc.Īlthough the speaker wire and cable connections required to do this can get confusing, the theory behind the process is pretty logical and straightforward. It’s not impossible, but it is complicated and, as I found, difficult to get right. Sadly, that proved to have some unexpected challenges.īecause consumer home theater hardware (the kind we humble 99-Percenters can afford, anyway) tops out at a speaker limit of 7.1.4 channels for Dolby Atmos and DTS:X, adding extra channels in the height layer (which both immersive sound formats should at least theoretically support) turns out to be a very involved Do-It-Yourself project. Having connected three home theater A/V receivers to expand my Dolby Atmos surround sound into a crazily convoluted 7.1.6 channel system, the next step was actually making it work.

Dolby atmos test disk