From AED Exhibition (S48):
1 x 15 inch, 1 x 1 inch
150W
103dB - 1W
The advantage of a coaxial speaker is easy: all the frequencies are coming from one source. The problem is that if you need a lot of speakers you lose this advantage. For personal monitors, Altec Lansing was way ahead of its time. From the nineties, all top speaker box-builders were coming to their senses in monitoring. All modern designs were done on coaxial technology. L-Acoustics and D&B are two of the top 5 manufacturers that used this technology from Altec Lansing. The past is still very modern. 

Altec Coaxial 604
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