Altec H-811B (documented 1955–1964)

Little is documented about the Altec H-811B. The period record shows it was a horn, Altec's 811B "Sectoral", made to mount on the company's high-frequency compression drivers. It was not a driver itself. The Archive has no manual, original spec sheet, or production dates for it. There are two period print mentions, and they tell a consistent story.

Altec's own advertising in High-Fidelity (July 1955, p.27) presented the 802C driver with the H-811B horn, together with the 3000A high-frequency speaker, as the only high-frequency components with a guaranteed range to 22,000 cycles. The same ad proposed the 802C/H-811B combination on an 803A low-frequency driver as a full-range custom system. It was guaranteed 30 to 22,000 cycles when mounted in a proper enclosure.

A 1964 equipment listing adds the useful details. HiFI-Stereo (1964, p.108) called the 811B a "Sectoral" horn, similar to the larger 511B but with an 800 cps cutoff. It was intended for use with the 804A driver and an 800 cps crossover. Dispersion was given as 90° horizontal and 40° vertical, and the listed price was $39.00.

That is the whole surviving record. No impedance, power handling, or dimensions appear in the Archive's files.

Known from period sources:

Type: high-frequency sectoral horn
Cutoff: 800 cps
Dispersion: 90° horizontal × 40° vertical
Crossover: 800 cps (with 804A driver)
Documented pairings: 802C driver (1955), 804A driver (1964)
Listed price: $39.00 (1964)

Market Value

┌──────────────────────────────────────────────────────────────────────────┐
│ ALTEC H-811B                                                    Nov 2026 │
├──────────────────────────────────────────────────────────────────────────┤
│ High      $786                                    Latest            $755 │
│ Median    $585                                    Trend                — │
│ Low       $371                                    Volume           ~1/mo │
├──────────────────────────────────────────────────────────────────────────┤
│   $800 ┤                                                                 │
│        │.                                                               .│
│        │                                                                 │
│   $586 ┤                                                                 │
│        │                                                                 │
│        │                                                                 │
│        │                               .                                 │
│   $300 ┤                                      .                          │
│        ├─────────────────────────────────────────────────────────────────│
│    vol │█                              █      █                         █│
│        └─────────────────────────────────────────────────────────────────│
│         2026-02                      2026-05                      2026-07│
└──────────────────────────────────────────────────────────────────────────┘

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