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http://arqen.com/acoustics-101/room-setup-speaker-placement/
https://ehomerecordingstudio.com/studio-monitor-positioning/
https://www.presonus.com/learn/technical-articles/studio-monitor-placement
https://www.thomann.de/blog/en/8-tips-get-best-studio-monitors/
https://www.musicianonamission.com/speaker-placement-101/