Uploaded June 2026 | Updated September 2026, 2 weeks ago

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Thanks to Koss for sending the A/550 for review!

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Audiophile Ninja Koss A/550 Cable: audiophileninja.com/product/koss-headphone-cable

Test Gear...

All music was digital in lossless or hi-rez FLAC or DSD formats either played locally or streamed from Qobuz (FLAC only), all through Roon.

Chain 1...

Apple iPad (10th Gen) USB output into Schiit Vestri (youtu.be/8zNzE_zHJzE) using both 4.4mm pentacon and 3.5mm TRS outputs

Chain 2...

Direct 3.5mm headphone output of Asus Zenbook S13 (2024 edition) Windows 11 laptop

Chain 3...

FiiO M33 R2R DAP (youtu.be/byeOH9YPAGc)

Chain 4...

FiiO SR11 streamer (youtu.be/YuagbK8p0FA) USB output into Schiit Asgard X w/ MESH DAC card (youtu.be/n8H8SN3Rdf4)

Chain 5...

Sonore opticalRendu Deluxe Edition (review coming) USB output into Berkeley Alpha USB DDC (youtu.be/94AvDeeRjHA) AES output into Berkeley Alpha S2 DAC (youtu.be/JY3c4HEyH0s) then XLR output into LTA Z10e (youtu.be/Bft6HUsYDhE)

Timestamps...

00:00 Intro, Pricing, Disclaimer
01:46 Shameless Self Promotion
02:17 Setup & Takeaways
03:26 Build, Comfort
06:04 Drivability
09:03 Sound
17:20 Comparison with Senn HD6xx & HiFiMan Edition XV
19:11 The Cabling System Was a Miss
28:18 Wrap-Up