I have a 600 and I don't think it benefits much from a better power cord. My gear sounds better plugged into my new DIY Oyaide outlet strip. The Gray, a parallel device, is plugged into that strip. I opened my Gray and changed an outlet to an Oyaide R1 before eventually getting the DIY Oyaide outlet strip(and taking the outlet back out of the Gray and putting it in the strip). When I opened up the Gray I saw that the wiring inside wasn't that great. The choke wire is only 18 gauge. So my advise is don't plug your gear into the Gray. Get a short as possible power cord for it. I'm using an older PS Audio Lab I reterminated with a 20A IEC.
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