I actually just hooked up an OCK-2 to my R26 and think it sounds great. It doesn't change the tonality at all, but it adds another layer of dimensionality into the music. Think of it of 2-5% extra 3D depth into things. More micro details as well. This is the type of change you hear with your eyes closed, but I toggled back and forth blind a lot of times and it was clearly better with the OCK-2. This isn't like rush out and buy it type of upgrade, but I'd add it to the list of eventual ones. I think upgrading the R26 fuse is just as impactful. This OCK-2 doesn't have a fuse upgrade yet. Also just using a cheap BNC cable it came with. Looking to upgrade those in the future...
I have yet to experiment with the N18Pro or LHY SW6. That is my next mission. I currently have my Eero node plugged into the R26 via an audioquest ethernet cable. Yes, the damn ethernet cable made a difference too when I tested it via amazon. By the end of souping this thing up I think the performance gains are probably like 20% at least. It should be after adding 2x the price to the DAC

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