: My Thule cross bars are pretty noisy until I put my kayak saddles on them.
: Same principle, break up the air flow into random turbulence. Orderly
: turbulence is called sound.

The wind deflector from Thule not only almost eliminated bar noise on my Honda,
the sunroof is now actually quieter than without the rack!

I would recommend these, save for the price (mine was secondhand). Next project:
plywood deflector stained to match the boat!