I think a sub adds value for music as well, especially if you enjoy pipe organ music. I supplement my KEF 104.2s below 80 Hz with a Velodyne HGS-15 and a Velodyne SMS-1 room correction module. It makes for a seamless integration that works well for music and HT. I use a vintage Proceed PAV/PDSD pre/pro with Proceed Amp 2 and Amp 3, so I use a separate HDMI switcher. The result is excellent audio and video.
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