A quarter-cubic-foot box that KEF built to monitor standard — and then dared you to call it small.

Overview

Six-point-seven litres. That's the whole enclosure — a hair over a quarter of a cubic foot, which is the figure KEF's own advertising leaned on repeatedly across 1979 and 1980. Into that volume the company packed a 110 mm bass driver and a 25 mm dome tweeter, and then did the thing that separates a Reference Series product from a parts-bin bookshelf: the two drivers were computer tested and matched to each other so that their specifications fell within 0.5 dB. Half a decibel. That is not a marketing tolerance, that is a production discipline, and it is the single most interesting fact about this speaker.

The Model 101 was introduced as a small loudspeaker in KEF's reference series, and the pitch was unusually blunt for the era. KEF's advertising, which ran in High Fidelity (August 1979, p.37) and again in Audio (August 1979, p.57), argued that a monitor-standard speaker had never before been both this small and genuinely high fidelity in one product — and that the Model 101 was the first time those two objectives had been met together. Whether or not you buy the "first time" claim, the framing tells you exactly who this was for: someone who needed an accurate small speaker to sit in a high-quality system without apologizing for its size.

KEF rated it for amplifiers of up to 100 W, with maximum output quoted at 98 dB SPL. Those are honest numbers for a box this size, and they set the expectations correctly — this is a nearfield-accurate monitor, not a party speaker.

Two engineering details distinguish the 101 from the crowd of small British two-ways of the period. The first is an overload protection device: an electronic circuit that continuously monitors the terminal voltage to each drive unit and attenuates that voltage when necessary. Note the design — it watches the terminal voltage to the drivers themselves, not a crude thermal fuse on the input.

The second is an anti-vibration gasket that acoustically isolates the bass drive unit from the loudspeaker enclosure. Decoupling a woofer from its baffle is standard practice now; in a 6.7-litre cabinet at the end of the 1970s it was a deliberate step to keep cabinet energy from feeding back into the cone. Together with the 0.5 dB driver matching, it explains why the 101 carried the Reference badge at a size that normally meant compromise.

Production ran from 1979, which suggests the model found a real audience — likely in broadcast, post-production, and the more serious end of the home market, where an accurate small speaker was a working requirement rather than a lifestyle purchase. Documentation on the deeper specification set (crossover points, impedance, sensitivity, cabinet dimensions, original pricing) has not surfaced in the Archive's materials, so those numbers are simply not stated here rather than guessed at. What is documented is enough to place the 101 precisely: a Reference Series two-way built to a matching tolerance most competitors never published, protected by a driver-level monitoring circuit, and sized to disappear into a room without disappearing from the music.

eBay Listings

As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.

Related Models

• KEF 100
• KEF 102
• KEF 103
• KEF 104
• KEF 104AB
• Braun AUDIO-1 (1965)
• Braun AUDIO-250 (1965)
• Magnavox Component Systems (1972)
• Acoustic Research AR (1967-1976)
• Acoustic Research 11