I haven’t heard the Wireworld Silver Sphere or the Platinum Starlight i2s/HDMI, however I am using their Ultraviolet 8 and Starlight 8 USB cables on my hard drive with excellent results. I’ve owned their Eclipes 7 interconnects and speaker cables and they performed very well. The Wireworld i2s/HDMI cables come highly recommended.
I’ve been in in contact with Tubulus, they offer true high end i2s cables. Tubulus i2s cables are specifically designed for i2s audio. Which makes it possible to use solid core conductors with air insulation. This isn't found in many high end HDMI cable and therefore Tubulus i2s cables should perform very well.
I’m currently using a Purist Audio Design Diamond i2s between a Jay’s Audio CDT2-MK3 Transport and the Denafrips PontusII 12th DAC. Sonically I favor the Purist over my Audioquest Carbon i2s/HDMI in my system. The PAD Diamond HDMI has a dead quite background and relaxed presentation while still retaining good resolution and transparency and is a great option at the price point. It’s warmth is due to a combination of musicality and natural, relaxed presentation without being dark or rolled off.
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