Originally Posted by Redwood
One of these would be what you need to use...
This is a plumbing fitting...
Not a radiator hose...
Not surgical tubing...
A Plumbing Fitting...
Those Fernco couplers are pretty stiff.
I had something in mind more like the coupler on page 14 of
"Series "VMS" and "VMT"
Quiet-Sphere Flexible Connectors
Single-sphere (VMS) and twin-sphere (VMT) connectors are
molded of neoprene and synthetic fiber and furnished with
corrosion resistant floating steel flanges. Operating temper-
ature to 240°F and operating pressure to 214 psi.
Compensates for expansion, compression, transverse
movement, and angular deflection. Reduces vibration and
noise transmission. Size 1-1⁄4" to 20" I.D. "
if somebody makes a residential version of this coupler.
The graph on page 2 of the link shows the dependence on frequency.