g.711 has such low latency because it doesn't take advantage of inter-sample redundancy in any way whatsoever - it's just raw 8-bit samples at 8 ksps with a com

g.711 has such low latency because it doesn't take advantage of inter-sample redundancy in any way whatsoever - it's just raw 8-bit samples at 8 ksps with a compander on either end (traditionally on the analog side of the DAC and ADC).