KLH

Henry Kloss's first act — affordable speakers that didn't compromise

History

KLH, founded in 1957 in Cambridge, Massachusetts, stands as a pillar of American high-fidelity audio history. The brand was established by three visionaries: Henry Kloss, a legendary audio engineer known for his work at Acoustic Research; Malcolm S. Low, a skilled businessman; and Josef Anton Hofmann, a concert pianist and son of the famed classical musician. Their mission was clear: to deliver scientifically designed, high-performance audio equipment at accessible prices. The name KLH was derived from the first initials of the founders’ last names—Kloss, Low, and Hofmann. KLH’s first breakthrough came in 1958 with the Model One, one of the earliest bookshelf speakers to utilize acoustic suspension technology, a revolutionary design pioneered by Edgar Villchur and licensed through Acoustic Research. This technology allowed for tighter bass response and reduced distortion in compact enclosures, making high-fidelity sound practical for average living rooms. The success of the Model One paved the way for a series of iconic speakers, most notably the Model Six in 1960—a floorstanding acoustic suspension speaker that became a benchmark for performance and value. Throughout the 1960s, KLH expanded its lineup with innovative products like the Model Eight, a combination FM radio and acoustic suspension speaker, and the Model Five, a compact speaker that became one of the best-selling hi-fi speakers of its era. In 1964, KLH was acquired by the Singer Corporation, marking the beginning of corporate ownership, though Henry Kloss remained involved until his departure in 1967 to found Advent Corporation. After decades of fluctuating ownership and brand dormancy, KLH was revived in 2017 under new stewardship, reintroducing modern versions of classic models while honoring the original engineering principles. Today, KLH represents a bridge between vintage American audio heritage and contemporary sound.

Key Facts

Fact	Detail
Founded	1957, Cambridge, USA
Founder	Henry Kloss, Malcolm S. Low, Josef Anton Hofmann
First Product	Model One (1958) – Acoustic suspension bookshelf speaker
Golden Era	1958–1970
Famous Feature	Acoustic suspension design for deep, clean bass in compact cabinets
Current Status	Active under new ownership since 2017, producing modern reissues and new designs

Legendary Products

Model Six (1960)

The KLH Model Six is arguably the most iconic speaker in the brand’s history. A three-way, floorstanding acoustic suspension design, it delivered remarkably flat frequency response (45 Hz–20 kHz) and 108 dB sensitivity. Its combination of scientific accuracy, neutral tonality, and affordability made it a favorite among audiophiles and institutions alike. Used in university listening labs and homes across America, the Model Six set a standard for transparent sound reproduction.

Model Five (1968)

A compact two-way bookshelf speaker, the Model Five became one of the best-selling hi-fi speakers of all time. With its 8-inch woofer and acoustic suspension cabinet, it offered surprising bass extension and clarity for its size. Its affordability and performance made high-fidelity audio accessible to a generation of music lovers.

Model Eight (1963)

More than just a speaker, the Model Eight integrated a high-quality FM tuner with an acoustic suspension enclosure. It was one of the first all-in-one systems to deliver true high-fidelity sound without compromise, embodying KLH’s mission of bringing quality audio to everyday consumers.

Sound Signature

KLH speakers embody the New England sound that Henry Kloss helped pioneer at Acoustic Research before founding this company. The acoustic suspension design delivers bass that is deep, tight, and articulate — there is no boom or overhang, just clean low-frequency extension that belies the compact cabinet size. The midrange is open and transparent, with a clarity on vocals and acoustic instruments that makes these speakers feel like they are getting out of the way and letting the music speak directly to you.

The overall tonal balance is remarkably neutral for speakers of their era. KLH did not chase excitement or dramatic coloration — they aimed for accuracy, and they achieved it at price points that made genuine high-fidelity accessible to ordinary music lovers. The Model Six and Model Five are easy to drive, working beautifully with modest tube amplifiers or entry-level solid-state gear, which means building an entire vintage KLH system does not require a fortune.

Collecting KLH

The Model Six is the KLH collector's prize — a three-way floorstanding speaker that set the standard for transparent, neutral sound reproduction in the early 1960s. Pre-Singer Corporation examples (manufactured before 1964 under Henry Kloss's direct oversight) are the most desirable, carrying an authenticity that later production cannot match. The Model Five is one of the best-selling hi-fi speakers of all time and offers remarkable performance for its compact size.

The Model Eight, which integrates a high-quality FM tuner with an acoustic suspension speaker, is a fascinating collector's piece that embodies KLH's philosophy of bringing quality audio to everyday consumers. When shopping for vintage KLH speakers, condition of the foam surrounds is the primary concern — nearly all original surrounds will have deteriorated and need replacement. Speakers with professionally refoamed woofers, original crossovers, and clean cabinet finishes represent the best value. Restored pairs of the Model Six typically range from $400 to $1,200 depending on condition and vintage.

Competitors & Comparisons

KLH competed directly with Acoustic Research, Advent, and AR in the bookshelf speaker market. While AR focused on smaller dipoles, KLH offered broader lineups with more powerful bass. Compared to JBL or KLH, KLH’s sound is more neutral and less colored, favoring accuracy over excitement—a hallmark of its engineering-first philosophy.

Models

Audio Equipment

model-twenty-one-fm-radio — Compact solid-state FM tuner designed by Henry Kloss, known for warm sound and iconic mid-century design.

Music Systems

Model 20 — A portable stereo hi-fi system combining phonograph, AM, and FM functionality, introduced in 1965
Model 24 — An all-in-one FM stereo phonograph system combining a turntable and tuner, produced for a short run in the mid-1960s.

Speakers

Model 3 — A modern bookshelf speaker continuing KLH’s acoustic suspension legacy
Model 5 (1968-1977) — A floorstanding acoustic suspension loudspeaker that brought high-fidelity sound to a broad audience
Model 6 — A three-way floorstanding speaker that set a benchmark for accurate, affordable hi-fi sound
Model Five (1968-1977) — A compact two-way bookshelf speaker using acoustic suspension technology, introduced in 1968.
Model Nine (1968) — The KLH Model Nine was the first full-range electrostatic speaker, combining groundbreaking dipole sound with iconic mid-century design.
model-11 — The KLH Model 11 was the first transistorized portable stereo, packing a Garrard turntable, FM tuner, and acoustic suspension speakers into a suitcase.
model-12 — KLH Model 12 bookshelf speakers from 1962 featuring acoustic suspension design and warm, balanced sound.
model-21 — Compact bookshelf speakers designed by Henry Kloss, featuring acoustic suspension and warm, natural sound.
model-345-(little-baron) — Compact bookshelf speakers from KLH's 1968 lineup, featuring acoustic suspension design and walnut veneer cabinets.
model-eight-fm-radio (1961) — Compact solid-state FM radio with acoustic suspension speaker designed by Henry Kloss, known for warm high-fidelity sound and iconic mid-century design.
model-eleven-portable-phonograph (1963) — KLH Model Eleven Portable Phonograph from 1963, a compact 3-speed suitcase turntable with built-in speaker and Garrard mechanism.
model-forty-one-reel-to-reel (1966) — KLH Model Forty-One Reel-to-Reel from 1966 featuring 4-track stereo/mono playback and solid-state electronics in a classic wood cabinet.

Other Models

KLH - Affordable High-Fidelity Sound from an American Audio Legend — American speaker manufacturer founded by audio legend Henry Kloss. Known for affordable, high-quality acoustic suspension speakers that brought good sound to the masses through innovative engineering.
Model 20 — A portable stereo hi-fi system combining phonograph, AM, and FM functionality, introduced in 1965
Model 24 — An all-in-one FM stereo phonograph system combining a turntable and tuner, produced for a short run in the mid-1960s.
Model 3 — A modern bookshelf speaker continuing KLH’s acoustic suspension legacy
Model 5 (1968-1977) — A floorstanding acoustic suspension loudspeaker that brought high-fidelity sound to a broad audience
Model 6 — A three-way floorstanding speaker that set a benchmark for accurate, affordable hi-fi sound
Model Five (1968-1977) — A compact two-way bookshelf speaker using acoustic suspension technology, introduced in 1968.
Model Nine (1968) — The KLH Model Nine was the first full-range electrostatic speaker, combining groundbreaking dipole sound with iconic mid-century design.
model-11 — The KLH Model 11 was the first transistorized portable stereo, packing a Garrard turntable, FM tuner, and acoustic suspension speakers into a suitcase.
model-12 — KLH Model 12 bookshelf speakers from 1962 featuring acoustic suspension design and warm, balanced sound.
model-21 — Compact bookshelf speakers designed by Henry Kloss, featuring acoustic suspension and warm, natural sound.
model-345-(little-baron) — Compact bookshelf speakers from KLH's 1968 lineup, featuring acoustic suspension design and walnut veneer cabinets.
model-eight-fm-radio (1961) — Compact solid-state FM radio with acoustic suspension speaker designed by Henry Kloss, known for warm high-fidelity sound and iconic mid-century design.
model-eleven-portable-phonograph (1963) — KLH Model Eleven Portable Phonograph from 1963, a compact 3-speed suitcase turntable with built-in speaker and Garrard mechanism.
model-forty-one-reel-to-reel (1966) — KLH Model Forty-One Reel-to-Reel from 1966 featuring 4-track stereo/mono playback and solid-state electronics in a classic wood cabinet.
model-twenty-one-fm-radio — Compact solid-state FM tuner designed by Henry Kloss, known for warm sound and iconic mid-century design.