KR Audio 2A3 Vacuum Tube
Best vacuum tube for audiophiles seeking rich, authentic Class-A sound.
Experience unparalleled audio clarity and warmth with the KR Audio 2A3 matched pair. These expertly crafted, low-frequency triodes deliver 2-5 Watts of pure Class-A power, perfect for discerning audiophiles. Designed for compatibility with any well-designed 2A3 amplifier, they bring a pure sense of space, precise timing cues, and brilliant tone to your favorite recordings. KR Audio's commitment to quality ensures these tubes elevate your 2A3-based system, offering an immersive and emotionally engaging listening experience that solid-state devices struggle to match. Discover the legendary "tube sound" with these timeless vacuum tubes.
$1200.00
Owner Satisfaction
4.7
/ 5
Category Rank
421
/ 1719
#421 in Power Amplifiers
Price vs Category Average
-85%
Below average
Filament Voltage
2.5
/ V
Who it's for
- Audiophiles seeking an immersive and highly detailed soundstage
- Listeners prioritizing long-term reliability and premium craftsmanship
- Design-conscious owners wanting a centerpiece for their audio setup
Who should skip it
- Budget-conscious buyers looking for entry-level component pricing
- Users without the space or equipment for vibration isolation
- Owners of amplifiers requiring universal or plug-and-play compatibility
Performance breakdown
Sonic Warmth
Delivers the rich, textured harmonic profile audiophiles crave from triodes.
Soundstage Precision
Creates an expansive sense of space with pinpoint instrument placement.
Power Efficiency
Optimized for low-wattage Class-A setups requiring high-sensitivity speakers.
Manufacturing Quality
Expertly crafted construction ensures long-term reliability and consistent performance.
System Compatibility
Standardized design integrates seamlessly into any well-engineered 2A3 amplifier.
Emotional Engagement
Provides an immersive listening experience that brings recordings to life.
Key Specs
Filament Voltage
2.5 V
Filament Current
2.5 A
Amplification Factor
3.8
Maximum Plate Voltage
300 V
Maximum Plate Current
100 mA
Plate Dissipation
15 Watts
Operating Plate Voltage
250 V
Operating Plate Current
70 mA
Features
- Delivers 2-5 Watts of pure Class-A power for exceptional sonic performance.
- Meticulously engineered for a pure sense of space and brilliant tone.
- Fully compatible with well-designed 2A3 amplifiers.
- Provides an immersive and emotionally engaging listening experience.
- Renowned for warm, rich, and naturally textured sound reproduction.
- Ideal for high-quality, low-powered tube amplifiers prioritizing sonics.
- Directly heated triode tube contributes unique sonic characteristics.
- A legendary choice for DIY enthusiasts and boutique amp manufacturers.
What customers say
Customers consistently praise the KR Audio 2A3 Vacuum Tube for its exceptional sound quality and robust build. Many reviewers highlight the tube's ability to deliver a rich, detailed, and immersive audio experience, often noting a significant upgrade over other options. While a premium product, users frequently perceive its performance as justifying the investment, underscoring a strong sense of value for discerning audiophiles. The tube's reliability and consistent output also contribute to its high regard, making it a preferred choice for those seeking top tier audio components.
Know before you buy
Yes, these tubes are designed to be fully compatible with any well-engineered amplifier built for the 2A3 triode. They adhere to standard operating specifications, making them a direct drop-in replacement for standard 2A3 tubes.
KR Audio tubes are known for their meticulous construction, which typically results in a lower noise floor and improved micro-dynamics. You can expect a more refined sense of space, better timing, and a richer, more textured midrange compared to mass-produced alternatives.
While they are designed to work within standard 2A3 operating parameters, it is always best practice to check your amplifier's bias settings when installing new power tubes. Ensure your amplifier is configured for the 250V plate voltage and -45V grid voltage to achieve optimal performance.
Yes, these are supplied as a matched pair. Matching is critical for 2A3 amplifiers to ensure balanced performance, consistent gain, and stable operation across both channels.
These tubes are designed to deliver between 2 and 5 Watts of pure Class-A power. They are best suited for high-efficiency speaker systems where this low-wattage output can provide sufficient volume and dynamic headroom.
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