This month we hope to hear some vintage loudspeakers. Once again Eric will generously give us a glimpse and a listen from his fast growing collection. A pair of Altec -- Lansing A7 "Voice of the Theatre" loudspeakers and their domestic counterpart, the Altec Corona, will visit our listening room. As of this writing one crossover is misbehaving, so our demo may be mono, but interesting nonetheless. The A7 (pictured here) is the smallest of a line of loudspeakers Altec produced for use in theatres, auditoriums and studios. It consists of a low frequency driver, type 803A, coupled to a short horn and rear loaded to a "bass reflex" enclosure. This is crossed over through a type 800E 800Hz crossover to a type 802 high frequency driver connected to a type 811 B multi-cellular horn baffle, which spreads the high frequencies horizontally over a 120 degree arc (and about 40