Taken from Stereo Review, November 1961

THE ALTEC LANSING Model 353A is relatively bulky and heavy as integrated stereo amplifiers go these days, weighing some 35 pounds. In it are two 25-watt channels with complete control facilities. Altec supplies rather detailed specifications on the performance of this amplifier in the instruction booklet, and measurements confirmed them in practically every detail. Each channel delivered 25 watts over most of the audio range, from 30 cps to nearly 10,000 cps. Below 30 cps the available power fell to 9 watts at 20 cps, and the high-frequency power response rolled off gently to 15 watts at 20,000 cps. These measurements were made at 2 per cent harmonic distortion, with both channels being driven simultaneously. A clue to the listenability of the 353A was the fact that the intermodulation distortion was very low at normal listening levels - 0.2 per cent at 1 watt and 0.65 per cent at 10 watts. At 25 watts per channel, IM reached 1 per cent.

The tone controls, although perfectly adequate for their purpose, had somewhat less range (about 10 db of treble and bass boost and cut) than many I have used. Personally, I consider this a virtue, since excessive boost at the frequency extremes is a common cause of distortion and muddiness. Any program material or listening environment that cannot be corrected with the tone-control range provided in this amplifier is probably incapable of being corrected. The rumble filter had most of its effect at frequencies below 30 cps and was too gradual in its slope to be of much value. The loudness compensation, which can be switched out, is rather mild, affecting both highs and lows, but it does its job, if you find such compensation desirable, without the boominess that is characteristic of some loudness controls.

The 353A had unusually low hum levels on all in- puts, and the hum was inaudible under any conditions, even with maximum volume and bass boost on the phono input. Few integrated amplifiers do as well. Like most integrated amplifiers, the 353A generates a great deal of heat that must be dissipated. The output tubes are located in a row at the open back, separated from the other tubes and components by a metal shield that deflects their heat rear-ward. The cabinet has a unique double-walled construction on its top that helps exhaust the warm air. As a result, the cabinet never becomes unduly hot, provided the necessary ventilation is provided at the rear.

I would describe the Altec 353A as a rugged, well-constructed, and honestly rated stereo amplifier, capable of delivering excellent performance in the highest-quality stereo or mono systems. Its price is $225.00, including cabinet.

JULIAN D. HIRSCH

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