Valve Index Koss PortaPro headphone mod bracket.
thingiverse
This mod is documented here: https://www.jabawok.net/?p=206 In short, it fixes the terrible bass response on the stock Valve Index off-ear headphones by modding with Koss PortaPros and an EQ profile. I went to the effort of doing this because its such a vast improvement to Beat Saber having decent bass and crisp highs. You will need to cut the headband off your Koss PortaPros and re-wire them. Details can be found in a previous post here: https://www.jabawok.net/?p=184 Depending on your head size you may need to adjust the angle which can be done easily enough in blender.
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