KEF 104AB (circa 1979–1980)

Name: KEF 104AB
Brand: KEF

Most of what is known about the KEF 104AB comes from a handful of period reviews, mainly in Audio magazine. It appears to have been a floor-standing or large bookshelf loudspeaker from KEF’s late-1970s lineup, sitting alongside the Cantata and the 105 Series II. Era publications often style the name “104aB,” but it's the same variant.

Audio (December 1979, p.88) printed the full manufacturer’s specifications. Frequency range is 30 to 40,000 Hz and nominal impedance is 8 ohms. The dividing network is two-way, with an acoustically coupled low-end crossover at 45 Hz and an electrical crossover at 3,000 Hz (18 dB/octave slope). Sensitivity was rated so that 12.5 watts into 8 ohms produced 96 dB at one meter and 400 Hz in anechoic conditions. Continuous power handling was specified as 20 volts (50 watts) from 100 Hz to 2,500 Hz, dropping to 8 volts (8 watts) above 3,000 Hz. The cabinet measured 63 cm high × 33 cm wide × 26 cm deep (24.8 × 13 × 10.2 inches).

A three-position Acoustic Contour Control centered at 1,500 Hz allowed ±2 dB of adjustment. Connection was by a two-pin DIN connector or 4 mm sockets. The same Audio review noted that most American power amplifiers would not accept the DIN plug, so the 4 mm sockets were the practical option for US buyers. The review also included intermodulation distortion measurements and a three-meter room response graph, taken with the speaker against a back wall and raised 400 mm off the floor. The phase crossover was measured around 7 kHz.

The 104aB was also offered in kit form. Audio (October 1979, p.31) reported that KEF was making both the 104aB and the Cantata available as KEFKITS, which let buyers assemble a high-quality system at a lower cost.

Beyond these period references, little else is documented. No original price, exact production span, driver complement details, or user reviews have surfaced in the available record. The 104AB remains a model known almost entirely through its contemporary press coverage.

Frequency range: 30 – 40,000 Hz
Impedance: 8 ohms nominal
Dividing frequencies: 45 Hz (acoustically coupled), 3,000 Hz (electrical, 18 dB/octave)
Acoustic Contour Control: Three-position, ±2 dB centered at 1,500 Hz
Sensitivity: 96 dB at 1 m (12.5 W into 8 ohms, anechoic, 400 Hz)
Continuous power rating: 50 W (100 Hz – 2.5 kHz), reducing to 8 W above 3 kHz
Dimensions: 63 × 33 × 26 cm (24.8 × 13 × 10.2 in)
Connections: 2-pin DIN or 4 mm sockets