Equipment photographs · 2
1 / 2 · Duplex coaxial loudspeaker
Duplex coaxial loudspeaker·Author unknown·CC0Period advertising · 1
1 / 1 · Altec 604 original catalogue page — Altec Lansing equipment catalogue, 1947 (archive catalogue dating; no date printed on selected page)
Altec 604 original catalogue page — Altec Lansing equipment catalogue, 1947 (archive catalogue dating; no date printed on selected page)·Altec Lansing Corporation (Altec Lansing equipment catalogue, 1947 (archive catalogue dating; no date printed on selected page))·Period advertising/catalogue material; copyright retained by the original rights holder; reproduced for identification and historical commentary (fair use).Why it mattered
- 01
It became the reference coaxial monitor of mid-century broadcast and recording control rooms.
- 02
Its point-source geometry influenced later monitors, including UREI's 811/813/815 series.
- 03
Kennedy's FOH survey notes that the 604's compact point-source design also made it a choice for cinema preview rooms and small public-address systems.
Original pricing
No reliable period price located
2026 equivalent
Not calculated without a reliable original price.
Public price evidence was not sufficient to publish a defensible original figure.
Use in the field
Standard broadcast and recording monitor; basis of UREI's 811/813/815 line[1]
Manuals & original documents
No authoritative manual or original document has been located for this profile.
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Know more about 604 Duplex?
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