(https://twit.tv/shows/home-theater-geeks/episodes/1). Holman has done “audio direction” for Apple since 2011. Which was the year Apple “started to create a centralized and expanded audio and acoustics team” (https://www.forbes.com/sites/davidp...es-homepod-secrets-release-date/#30d11e224d6a). HomePod project began around 2012. He was listed as the inventor on a patent Apple filed Sep 13, 2014 for “Directivity optimized sound reproduction” (https://www.google.com/patents/US20170105084). (Which has apparently been referenced 11 times in subsequent patent filings by Sonos (https://www.google.com/patents/US20170105084#forward-citations). Who released their Trueplay calibration system in 2015.) Discussed here after it was published (http://www.patentlyapple.com/patent...und-system-invents-next-gen-audio-system.html). Also, posted here (https://forums.macrumors.com/thread...alogue-from-movies-more-intelligible.2105702/) by me. He created THX sound (manual room corrrection—I think) for movie theaters while working at Lucasfilm. (Says “THX” stands for “Tomlinson Holman crossover,” THX 1138 a fortuitous coincidence.) He says he came up with the term “5.1.” He cofounded Audyssey Laboratories, which makes the audio calibration technology (https://en.wikipedia.org/wiki/Audyssey_Laboratories#Technologies) that powers The Wirecutter’s current pick for AV receiver (https://thewirecutter.com/reviews/best-receiver/), in 2002. (Also, be sure to check out the eVR far field voice technology they’re advertising on their website (https://audyssey.com).) He was an advocate for left and right front height channels (popularized by Dolby as “Dolby Atmos” in 2012). And possibly using two subwoofers (one for each octave, 20-40 and 40-80Hz—I think). Toward the end of the podcast he talks about incorporating psychoacoustics into audio designs with digital signal processing. The “r/audiophile” review of HomePod by “u/WinterCharm” says Apple is using “Fletcher–Munson curves,” (a psychoacoustic finding of loudness perception) as part of its calibration process (https://www.reddit.com/r/audiophile/comments/7wwtqy/_/du4rp5j/?context=1).