Quieting my exhaust?

72 Swinger, 572. Has Cherry Bomb Extremes (12') on it. Kind of annoying, when going down the road at 55-70 MPH. Love the great sound, but would like to talk to the passenger.
Suggestions?
Should I try baffles in the pipes? Or, install some resonators? Kind of resonator, would be great too.
Thanks for any feed back.