Some models came with just the one top locking ring. I'm not sure what they are showing in my MC501 manual but it isn't how mine work. That may be an older connection type with the angled insert and locking screw.
Yeah, you don't have to crank them down too hard - just snug is good - and a good connection can make a difference in SQ.
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Michael 4K QLED|Aerial Acoustics|McIntosh D100 - MC501 - MX151|Bluesound|Schiit|Wyrd4Sound
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