FreeDV is a fully open digital voice protocol; unlike DMR, D-STAR and the rest, there are no patents tying it down. It uses very little bandwidth for voice. I just had my first QSO (thanks K5WH in Texas!) using this mode. While it does make voices sound a little robotic, there’s no static, no hiss, nothing unwanted. That’s what always put me off HF voice: trying to work out who is saying what through all the noise. FreeDV fixes that.
It’s quite a new protocol, so you don’t hear it much on the air yet. I hope to be making some more noise with it soon.