ResonantLive Sound Archive

Equipment file · Two-way horn loudspeaker in rock PA use

A7 rock PA stack

Altec Lansing · 1950s (in rock PA from the 1960s)

Evidence status · documented

Identity and core specifications are documented; some historical fields remain unavailable.

Bands of the 1960s and 70s adopted Altec's compact [[altec-a7|A7 Voice of the Theatre]], a 180-pound cabinet pairing a [[altec-515|515]] woofer in a bass horn with a [[altec-288|288]] or 902 driver on a multicell horn. Its 103 dB sensitivity suited the low-power amplifiers bands could afford.

Introduced
1950s (in rock PA from the 1960s)
Category
Two-way horn loudspeaker in rock PA use
Intended use
Cinema loudspeaker repurposed for band PA
Production
Altec Lansing; reissued 2004

Why it mattered

  1. 01

    Its efficiency made amplified music practical before high-power amplifiers, and it became the standard club and rock PA box of the 1960s–70s.

  2. 02

    It carried cinema horn engineering directly into touring PA, before purpose-built systems like the [[community-leviathan|Community Leviathan]].

Engineering record

Woofer
515 15-inch woofer in a folded bass horn[2]
Sensitivity
103 dB (1 W/1 m)[1]

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

A common PA choice for rock bands and club systems in the 1960s and 70s[1]

Manuals & original documents

Sources

  1. 11947 Altec Lansing Voice of the Theatre SpeakersMix · technical paper · 2006-09-01
  2. 2Voice of the Theatre A7 Owner's ManualAltec Lansing · manual

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