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ET250S - 250 Watt/Channel Amplifier

Now You CAN Have It Both Ways

The lucidity and harmonic “rightness” of a tube amplifier and the muscle and control of a solid-state amplifier.

Introducing the conrad-johnson ET250S enhanced triode amplifier. A single-ended triode for voltage gain establishes the harmonic character of the ET250S, while a high-current, high damping factor transistor output stage produces the muscle (250 watts/ch) and control.

The conrad-johnson Enhanced Triode (ET) Amplifiers are power amplifiers designed to capture the best attributes of both fine vacuum-tube designs and of the best solid-state designs. The ET250S is a 250-watt per channel stereo power amplifier with a sophisticated zero-feedback circuit that offers the refinement of a vacuum-tube amplifier with the guts and control of a solid-state amplifier. We have found that eliminating loop negative feedback can result in much finer gradations in dynamic response (micro-dynamics) and more accurate decay on musical transients. But eliminating negative feedback requires much more care in the design of the circuits - both in choosing devices and in power-supply design.

For our enhanced triode amplifiers, voltage gain is provided by a pair of 6922 vacuum tubes. The high amplitude signal produced by the voltage gain stage is then efficiently coupled to the loudspeaker system through high-current bi-polar devices. This contributes the fast, weighty bass and seemingly limitless power reserve that are notable in these amplifiers.

Rock solid power supplies are needed to enable the audio circuits to reach their potential on musical transients. The ET250S features an oversized main power transformer and massive power storage reservoirs with high-speed capacitor shunts to deliver quick, even startling transient response.

conrad-johnson components are internationally known for the quality of their parts, and the ET 250S is no exception. The audio circuits and their related power supplies utilize precision low inductance laser-trimmed metal foil resistors. The circuits employ polypropylene, polystyrene and Teflon capacitors extensively, except in the main power supply storage, where high-speed electrolytics are used because of the extremely high capacitance required. Precision-machined input/output connectors have been carefully selected for optimal sonic performance. Even the internal wiring is chosen on the basis of its sound quality in its specific application.

Thoughtful engineering, specification of top quality component parts, and painstaking care taken in production make the ET250S capable of extraordinary performance in music reproduction. Available Immediately. We invite you to arrange an audition with your conrad-johnson dealer to confirm for yourself the extraordinary musicality of these amplifiers.