Subscriber loudspeaker "D-3".

Subscriber loudspeakers.DomesticThe subscriber loudspeaker "D-3" presumably since 1938 has been produced by the Moscow Machine-Building Plant. The subscriber loudspeaker had the name "D-3" by the type of speaker, had high frequency characteristics, 30 ... 7000 Hz and output power from 0.35 to 0.8 W.