Archimago's Musings: Modding the Dekoni Blue ("Arch-Mod5"). Streaming audio: Apple Music to be "true hi-res lossless" stereo with multichannel (Atmos) in June.
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Argon — Mod House Audio
The Mod Collective: Bring all your full sized headphone mods here. | Headphone Reviews and Discussion - Head-Fi.org
Cheap Tweaks: Audeze and HiFiMAN Headband Comfort Mod - The Sound Apprentice
Headphone Recable / Mod Service - Ballista audio cable features 28 strands of UP-OCC and silver clad UP-OCC, each isolated for pure sound