Conrad-Johnson
Conrad-Johnson ART 27A Power Amplifier
Best high-end amplifier for audiophiles seeking pure, tube-driven musical warmth.
Experience unparalleled musical fidelity with the Conrad-Johnson ART27A Stereo Power Amplifier. This limited edition amplifier, with only 250 units produced, is engineered for the most discerning audiophiles. It delivers 36 Watts per channel in pure Class A operation, utilizing triode-configured KT88 tubes for exceptional clarity and warmth. The ART27A features independent, discrete regulated power supplies for each stage, ensuring pristine signal integrity. Built with the highest quality components, including precision Vishay resistors and proprietary Translinear output transformers, it promises enduring performance and sonic accuracy.
$21000.00
Owner Satisfaction
4.9
/ 5
Category Rank
4
/ 1719
#4 in Power Amplifiers
Price vs Category Average
+154%
Above average
Power Output
364
/ Watts rms per channel (into ohms)
Who it's for
- Collectors prioritizing long-term reliability and premium build quality
- Audiophiles seeking natural, lifelike musical reproduction
- Listeners pairing the amp with demanding, high-end loudspeakers
Who should skip it
- Owners with limited rack space or poor ventilation
- Budget-conscious buyers seeking high-value audio equipment
- Listeners wanting a low-maintenance, set-and-forget audio system
Performance breakdown
Sonic Transparency
Pure Class A circuitry delivers an incredibly lifelike and transparent soundstage.
Build Integrity
Premium components and discrete power supplies ensure lasting, high-fidelity performance.
Tube Warmth
Triode-configured KT88 tubes provide that signature rich, organic harmonic texture.
Power Efficiency
Thirty-six watts requires high-sensitivity speakers to truly shine in larger rooms.
Signal Purity
Independent regulated power supplies keep noise floors exceptionally low and clean.
Exclusivity
Limited production of only 250 units makes this a true collector's piece.
Key Specs
Power Output
36 Watts rms per channel (into 4 ohms)
Amplifier Class
Class A, Tube
Frequency Response
20 Hz to 20 kHz, +/- 0.25 dB
Total Harmonic Distortion
Less than 1.5% THD (30 Hz to 15 KHz)
Tube Complement
3 x 6922, 4 x KT88 (matched pairs, selected)
Input Impedance
100 kOhms
Output Impedance
4 Ohms (also available connected for 8 or 16 ohm loads)
Dimensions
17.5D x 19W x 8.875H inches
Features
- Limited edition, reference-quality stereo power amplifier
- Pure Class A operation with KT88 output tubes
- 36 Watts RMS per channel for efficient systems
- Independent regulated power supplies for optimal signal purity
- Proprietary Translinear output transformers
- Precision-crafted with premium internal components
- Designed for exceptional musical accuracy and longevity
- Phase-correct operation throughout
What customers say
The Conrad Johnson ART 27A amplifier is celebrated for its exceptional sonic purity and musical reproduction. Owners consistently praise its ability to blend rich, classic tube musicality with modern speed and transparency, largely due to the KT150 tubes. A key theme is the creation of a vast, holographic soundstage with precise imaging and excellent instrument texture. The amplifier delivers effortless power, maintaining detail during complex music. While positioned at a high price point, the consensus is that the performance justifies the investment, forging a deep emotional connection to the music. For many dedicated listeners, the ART 27A sets the current high end benchmark.
Know before you buy
Because this amplifier operates in pure Class A, it is best suited for high-efficiency speakers. While 36 watts per channel is substantial for a tube design, it will perform most dynamically with speakers that have a sensitivity rating of 90dB or higher.
Yes. While the unit is factory-configured for 4-ohm loads, it can be internally reconfigured to support 8-ohm or 16-ohm speakers. This ensures optimal power transfer and damping regardless of your speaker's impedance requirements.
The triode-configured KT88 tubes provide a signature blend of warmth and harmonic richness while maintaining excellent clarity. By operating in pure Class A, the amplifier avoids switching distortion, resulting in a highly linear and musical soundstage.
Each stage of the amplifier features its own discrete regulated power supply to prevent crosstalk and signal interference. This design choice ensures that the signal remains pristine and stable, even during complex musical passages.
Like any high-end tube amplifier, the ART27A uses matched pairs of tubes that will eventually require replacement to maintain peak performance. Because this model uses premium, selected components, we recommend sourcing replacements through authorized service channels to ensure the amplifier's sonic integrity remains intact.
No, the ART27A is designed exclusively for single-ended operation and features RCA input connectors. It is optimized for high-quality unbalanced signal paths to maintain the purity of the audio signal.
Still have a question?
Ask Hayley anything about this product before you decide.