KLH Model 33 (1968–1969)

The KLH Model 33 is a compact FM/AM table radio introduced in 1968 with a list price of $79.95. It's an eight-tube superheterodyne design — a notably tube-heavy complement for a table set of this era, including the 6BA6, 12BA6, 12BE6, 12AV6, 12AU6, 35C5, 50C5, and a DM70. The tube lineup and the selenium rectifier in the power supply place it firmly in the transitional period before solid-state took over consumer radios.

Physically, it's a small unit: 10.875 × 4.375 × 7.125 inches, weighing 6 lb 10 oz. It runs on 117V AC, draws 18W, and puts out 1W undistorted. The built-in speaker is listed in the source as "1 - 4 inch," a notation that's ambiguous — it isn't clear whether that's a single 4-inch driver or something else, and the record doesn't clarify. FM coverage spans 88–108 MHz with a 75-ohm dipole antenna; AM covers 530–1620 kHz via a built-in ferrite rod. Frequency specs appear twice in the record with different values: one page gives a range of 50–15000 Hz, another gives a response of 70–15000 Hz ±3 dB. Both are listed here as they appear to be different measurements.

Documentation on the Model 33 is thin. The radiomuseum service page references circuit diagrams dated September 1968 and indicates authorized service literature (schematics) exists, but beyond that, little is recorded about this model's reception or market position. A forum mention of a "low volume issue" on the unit exists but no resolution or detail was captured. One source gives the production run as 1968–1969; another only confirms an introduction year of 1968. In a period review, High Fidelity described the Model 33 as having a smooth, open, and well-balanced response (June 1970, p.87).

Known specs: