Protocols and standards
Super G3
Super G3 refers to Group 3 fax machines fitted with the V.34 modem, which transmit at up to 33.6 kbit/s instead of the 14.4 kbit/s of classic fax.
It is not a new generation but an extension of Group 3, described in the fax negotiation standard. A Super G3 machine remains compatible with all others: facing an older machine, it falls back to the usual speeds. It requires error correction, without which its speed would be unusable.
Why it matters for fax
The time saved is real on an analogue line, but on today's networks it is often the opposite: a failed V.34 negotiation wastes more time than it saves. Disabling a machine's Super G3 mode is one of the first settings recommended when faxes fail through a broadband router.