Conrad-Johnson GAT

Written by on 11/13/2017 in New Product at CS - No comments


The GAT Series 2 Preamplifier embodies conrad-johnson’s latest advances in line-stage preamplifier technology.
It is believed that the GAT2 will quickly be recognized as a new industry-wide reference standard for line-stage preamplifier performance, a role filled for more than a decade by its legendary predecessor, the ART preamplifier. Like the ART, the GAT Preamplifier will be available in a numbered, limited edition of 250 units which will be sold through selected CJ dealers.

The GAT Preamplifier is a vacuum-tube, line-stage preamplifier that looks as good as it sounds. It is also notable for convenience and ease of use. The unit features input selection and ladder-type level adjustment by microprocessor-controlled precision-contact relays. Level and balance can be adjusted in 100 steps of approximately .7 dB per step. All functions can be controlled by the hand-held wireless remote control.

The circuitry of the GAT Preamplifier is elegant in its simplicity. The audio circuit consists of a single amplifier stage incorporating one composite triode comprised of paralleled sections of a high-transconductance miniature dual triode vacuum tube. This amplifier stage is coupled to the preamplifier outputs through a high-current MOSFET buffer, which achieves a very low output impedance, making the GAT extremely flexible in the choice of interconnect cables and partnering amplifiers.

DC voltage is supplied to the circuit by CJ’s latest discrete voltage regulators that isolate the audio circuit from the power line by maintaining negligible impedance across the audio frequency band. Infrasonic noise is minimized by operating the tube filaments (heaters) on a dc voltage supplied by another discrete regulated power supply.

Considerable care and attention have been paid to the physical aspects of the design. Microprocessor controlled relays, used for selecting sources and level, are located right at the input connectors, keeping signal paths short to minimize cross-talk and interference between channels and inputs. The vacuum-tubes are isolated by a suspension system designed to minimize microphonics. The dramatic casework features attractive clear Lucite tube guards outside the chassis, allowing for easy access for tube replacement.

Conrad-Johnson we have long appreciated that the full potential of any circuit can only be realized by using the finest available parts. Each part for the GAT has been selected on the basis of both sonic performance and long-term durability. The audio circuit (including the level control) is executed entirely with precision metal foil resistors and proprietary CJD Teflon capacitors. Tubes have been carefully hand selected for minimum noise and microphonics.

The DC regulated power supplies use the same quality resistors as the audio circuits. Capacitors for the power supplies are exclusively polypropylene and Teflon – there are no electrolytic capacitors in the audio circuits or their related power supplies. All signal switching is done by special relays designed for signal applications. These relays are sealed and have gold plated silver precision contacts. Input and output connectors are machined from oxygen free copper, and are gold plated.

The GAT is built without compromise to achieve a new standard in musical performance, and like its renowned predecessors, it is built to last.

At our demonstration facilities we have the Conrad Johnson GAT, ET3 and our much loved legacy Premier 16LS line stages on hand for an enlightening introduction to the craft.

About the Author

Audio Engineer, Critic & Retailer twenty-seven years in the making.

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