Altec 210A (1960s–1970s, approx.)
The Altec 210A is a two-way, full-range Duplex speaker system. A single chassis carries a 12-inch woofer with a coaxially mounted compression-driver horn tweeter, and the horn sits inside the woofer's magnet structure. It was built as a professional monitor for recording studios and broadcast work, a near-field design for close-range listening in control rooms and radio booths. It's a "Pro" model, marked "Pro 210A" on the cabinet.
The 210A is described as an evolution of the more famous 605A Duplex. It's a high-efficiency design, roughly 95 dB sensitivity, with an 8-ohm nominal impedance and a frequency response in the ballpark of 60 Hz to 16 kHz. The crossover is built into the driver assembly. The tweeter uses an aluminum diaphragm with an Alnico magnet. The cabinet is a ported/reflex enclosure in black hardwood plywood with a perforated metal grille. Approximate dimensions are 22"H × 18"W × 12"D, weight is around 45 lbs, and there's a single pair of input terminals. Power handling is rated at 30 watts RMS, so it suits low-power tube amplifiers well.
The record on the 210A is thin. No exact production years, no original price, and no detailed test measurements survive in the usual trade press. What exists comes from owner accounts and a single marketplace listing. Owners describe the sound as "punchy, lively, and detailed," with a tight, fast low end, though the horn can come across as forward or aggressive on some material. It doesn't have the deep bass of a larger floorstander, but imaging is reportedly excellent. Audio (October 1968, p.99) listed Altec among the exhibitors at the 1968 New York High Fidelity Music Show, though the 210A itself doesn't appear to have been reviewed in the major hi-fi magazines of the period.
Common problems: foam woofer surrounds prone to dry rot, crossover capacitors that drift and dull the high end, and debris in the tweeter gap that cuts output. They're not hard to work on, since surrounds and off-the-shelf electrolytic capacitors are readily available. Replacement tweeter diaphragms can be hard to source.
- Two-way Duplex: 12" woofer + coaxial compression horn tweeter
- Sensitivity: ~95 dB/W/m
- Frequency response: approx. 60 Hz–16 kHz
- Nominal impedance: 8 ohms
- Power handling: 30 W RMS
- Ported/reflex cabinet, black hardwood plywood
- Approx. 22" H × 18" W × 12" D, ~45 lb
eBay Listings
As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.