Some examples of how FreeDV RADEV1 sounds under various conditions. In particular there are A/B comparisons with single sideband.

Note that these A/B tests performed in the FreeDV app are not completely fair as most users run at 50% power when transmitting FreeDV’s OFDM signal so a real sideband signal would be at twice the power. Also, a sideband transmission would often have compression turned on.

Having said that, the difference is striking.