Conrad Johnson ET5 Enhanced Triode Tube Preamplifier CJ Serviced in 2023
Item History - Pre-owned
Manufacturers Description - This information is to be used for reference only. Because the item may be pre-owned, accessories or warranties mentioned in this section may not apply to this specific item. Please check the “Included Accessories” section and photos for more details..
The audio circuit is elegant in its simplicity.
An audio amplifier stage consisting of a single-ended triode amplifier provides the voltage gain. This amplifier stage is connected to the preamplifier outputs through a high-current MOSFET buffer, which achieves a very low output impedance, making the ET5 extremely flexible in the choice of interconnect cables and amplifiers.
DC voltage is supplied to the circuit by our latest discrete voltage regulator that isolates the audio circuit from the power line by maintaining negligible impedance across the audio frequency band. Infra-sonic noise is minimized by operating the tube filaments (heaters) on a dc voltage supplied by a separate regulated power supply. The ET5 is also notable for convenience and ease of use. The unit features input selection and level adjustment by microprocessor-controlled relays, with controls available both at the front panel and via a full-function remote.
All control functions of the ET5 operate through microprocessor-controlled relays. For the level control, the relays select combinations from a network of precision, low-noise metal foil resistors to effect loudness and balance changes in 100 steps of approximately .7dB per step. All switching and adjustment can be controlled by the unit’s remote control. A Theater Mode, which passes the input signal through at unity gain, makes it simple to incorporate the ET5 into a high quality home theater system without compromising its two-channel performance.
Like its bigger brother, the GAT, the ET5 is constructed from the highest quality, carefully selected parts for unrivaled sonic performance and reliability.
Tubes have been carefully hand selected for minimum noise and microphonics. The same CJD Teflon capacitors that distinguish the GAT are used in the ET5 for output coupling and post-regulator power supply storage. All other capacitors in the audio circuits and related power supplies are polypropylene or polystyrene – there are no electrolytic capacitors in the audio related circuits. The resistors in these circuits (including the two dozen level control resistors) are special low inductance, high-precision laser-trimmed metal foil resistors. Switches are sealed relays with gold-plated silver contacts. Input and output connectors are premium quality custom machined parts.
Gain: 25 db Maximum output: 20 vrms Output impedance: 100 ohms Distortion: less than .15% THD at 1.0 Vrms output Frequency response: at unity gain 2 Hz to more than 100Khz Hum and noise: 100 db below 2.5 v Tube complement: 1 x 6922
15.375D x 19W x 4.94H inches
Functional Condition - Full Functionality - This item is in full working order with all features operational.
Functionality Notes (if any) - Few signs of cosmetic wear on the ET5. The remote does have some wear.
Cosmetic Condition - Above Average - The item shows a less than average amount of wear for its age.
Cosmetic Notes (if any) - This preamp was serviced by Conrad Johnson in March of 2023. It is completely functional. The remote does have an issue in the battery compartment as shown but it is functional.
Included Accessories - ET 5 preamp, Remote control, Power cable, Original box