Amateur Radio Magazine, the journal of the Wireless Institute of Australia published “The time has come for digital voice on the HF bands” in the December 2025 edition. They’ve made the article available for download here: https://www.wia.org.au/members/armag/2025/november/documents/AR%20Issue%206-2026_pp42-48_2.pdf

Digital voice modes are well
known on VHF and above. DMR,
D-STAR, System Fusion, and P25
to name a few. All of these are
proprietary to some extent, with most
using the AMBE vocoder. DMR has
become very popular due to the low
cost of radios that support it.
Th e potential of digital voice over
HF is to have a voice contact with
zero background noise, high fi delity
audio and good immunity to noise
and fading.

Thanks AR magazine.