KLH Model One (1959–1962)

The KLH Model One was the first speaker KLH ever made. It came out in 1959 as part of the company's debut lineup, alongside the Model Six. Built in Cambridge, Massachusetts, it was a compact two-way bookshelf speaker with an acoustic suspension design - the sealed-cabinet approach that company founder Henry Kloss championed and that made deep bass possible from a small enclosure. The Model One paired a 10-inch woofer with a 2-inch tweeter. It was the smaller sibling of the Model Five and Model Six. The Model One and Model Six shared the same driver complement; the difference was cabinet size.

It was also the first loudspeaker designed to be used with transistor amplifiers. Sources differ a little on the fine print. Frequency response is given as 47-25,000 cycles by one and 50-25,000 Hz by another. The broadly cited figures are an 8-ohm impedance, 40-watt power handling, a 1.8 kHz crossover, and a weight of 35 pounds. Dimensions are approximately 23.8″ h × 12″ w × 10-1/4″ d. Original price was $89, though a 1961 Lafayette Radio catalog listed it at $95 each.

Surviving documentation on the Model One is thin. No period reviews, owner impressions, or detailed sound assessments have surfaced, and little is documented about common failure modes or restoration needs. It was the speaker that started KLH, and it introduced the acoustic suspension technology that defined the company's early reputation.

Type: 2-way, 2-driver closed-box bookshelf speaker
Drivers: 10″ woofer, 2″ tweeter
Impedance: 8 ohms
Power handling: 40 watts (recommended amplifier: 15–40W)
Crossover: 1.8 kHz
Frequency response: 47–25,000 Hz (varies by source)
Dimensions: 23.8″ × 12″ × 10-1/4″
Weight: 35 lbs
Original price: $89–$95 each