A speaker system developed in collaboration with the BBC in the United Kingdom.
The LS5/1A has a 2-way 3-speaker configuration that combines a 38cm woofer with two 3.8cm direct radiators, and is directly connected to a dedicated power amplifier (output 35 W).
The direct radiator that handles the high range is driven in parallel from 1750Hz to 3kHz, and it is designed to operate with only one unit above 3kHz. This has improved the phase characteristic of 3kHz or more.
The LS5/1A was subsequently upgraded to the LS5/1AC.