From another Audiogon post:
" Compared with and 8 ohm speaker, a 16 ohm speaker requires that the amplifier put out twice the VOLTS for a given power, because it draws half the amps [amperage]. Solid state amps are limited by the volts they can output...within reason (and until a fuse pops) they can hold up this voltage regardless of the current drawn. Thus their wattage rating increases for lower impedance speakers. Tubes have high voltage capability, but can output little current, therefore tubes are usually interfaced using a step-down transformer which trades off voltage for current. This transformer has different taps (connection points) on its secondary winding so as to match different speaker impedances, so that the amp will work equally well with any impedance."
https://forum.audiogon.com/discussions/16-ohm-speakers-pros-cons
" Compared with and 8 ohm speaker, a 16 ohm speaker requires that the amplifier put out twice the VOLTS for a given power, because it draws half the amps [amperage]. Solid state amps are limited by the volts they can output...within reason (and until a fuse pops) they can hold up this voltage regardless of the current drawn. Thus their wattage rating increases for lower impedance speakers. Tubes have high voltage capability, but can output little current, therefore tubes are usually interfaced using a step-down transformer which trades off voltage for current. This transformer has different taps (connection points) on its secondary winding so as to match different speaker impedances, so that the amp will work equally well with any impedance."
https://forum.audiogon.com/discussions/16-ohm-speakers-pros-cons