My 7 speed shimano nexus roller brake/freehub on my Schwinn Varsity is my favorite sounding one, Shimano 105 7 speed freehub on my Miyata 1000 is a close second.
I notice people on the road with newer 10sp freehubs that I don't enjoy the sound of. Very harsh.
I just finished working on a 70's Peugeot UO-8 with whatever the original freewheel was and I didn't really care for the sound of that either. Too Bright sounding.
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--Don't Panic.