The earliest audio amplifiers made use of small, 3 element valves known as directly heated triodes. For many, the simple circuits that can be built around such devices better preserve the structure, colour and feeling within the music than any other circuit topology. One of the best sounding triodes, the 2A3, is in production again and its characteristic linearity has been employed in a novel configuration to create a particularly charming amplifier. The puresound 2A3 is an 18 Watt per channel line level integrated design that allows for the selection of up to 3 different source components and control of the volume by a high quality ALPS Blue Velvet potentiometer. There are many amplifiers now making use of directly heated triodes but few which adequately address the particularly awkward issues involved in driving these devices properly. The puresound 2A3 amplifier features an unusual choke loaded driver stage which allows the 6SN7 driver valves to deliver the full measure of signal to the push/pull output valves. This rather exotic configuration usually results in a tremendous depth to the tone of instruments and the puresound 2A3 is no exception in this regard. Very high quality components are used throughout including selected carbon film resistors and SCR polypropylene capacitors. The power supply makes use of twin valve rectifiers and choke smoothing. The output can be configured for use with 4 or 8 ohm loudspeakers. The puresound 2A3 may also be used as a very high quality stereo power amplifier if the volume control is turned up fully.
