Complex sentence: As well as making very efficient use of transmitter power, it also uses very little band space, as (with disciplined operating) at least twenty simultaneous PSK31 contacts can be carried out side-by-side in the bandwidth required for just one voice contact.
Split into simpler sentences: As well as making very efficient use of transmitter power, it also uses very little bandwidth. As a result, with discplined operation at least twenty simultaneous PSK31 contacts can be carried out side-by-side in the bandwidth required for just one voice contact.