5963 / 12AU7 / ECC82 GE NOS Matched Pair - Long Gray Plates - AMPLITREX Tested - Made in USA

5963 / 12AU7 / ECC82 GE NOS – Matched Pair – Long Gray Plates – Halo Getter – Made in USA – Low Noise & Microphonics – Amplitrex Tested – Test VERY STRONG

Description:

This matched pair of NOS General Electric 5963/12AU7/ECC82 , made in the USA, represents one of the most reliable and musically balanced American versions of the 12AU7 family.

The 5963 designation identifies the industrial variant of the 12AU7, designed for stable and continuous operation in professional equipment. The construction with long gray plates and halo getters is typical of GE's quality production, characterized by mechanical robustness and electrical consistency.

The tubes are authentic NOS , selected as a Matched Pair , classified Low Noise & Microphonics and tested in our laboratory on an Amplitrex AT-1000 , with a VERY STRONG result. A pair ready for hi-fi and professional level applications.

Sound Characteristics

Bass: Solid, compact, and well-controlled. The low range is structured and linear, with good articulation and natural support for the musical message.

Mids: Clean, balanced, and natural. Vocals are clear and well-focused, while acoustic instruments and piano maintain harmonic coherence and timbre accuracy.

Highs: Extended and uncluttered. The upper range is airy yet disciplined, with a fine grain and no harshness.

Dynamics: Smooth and stable. Excellent microdynamics and prompt transient response, with consistent performance even in the most complex passages.

Soundstage: Wide and well-organized soundstage, with good depth and natural separation of sound planes.

🎧 Use in Hi-Fi Amplifiers

Ideal for:

• line preamplifiers
• driver stages
• integrated amplifiers and power amplifiers that require stability and silence

Particularly suitable for systems that prioritize balance, reliability and timbral correctness.

🎸 Use in Music Applications

Also very valid in:

• instrument amplifiers
• studio equipment
• sensitive positions thanks to the Low Noise & Microphonics classification

They offer predictable behavior and controlled harmonic output.

🎯 Note for audiophiles and technicians

• General Electric Production – Made in USA
• Industrial version 5963
• Long Gray Plates – Halo Getter
• NOS – New Old Stock
• Matched Pair selected
• VERY STRONG test on Amplitrex AT-1000
• Low Noise & Microphonics

A solid and reliable pair, an expression of American GE production, designed for those who want operational stability and balanced musicality in full Vacuum Tubes Treasures style.

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Test Results:

Valve tested on AMPLITREX AT-1000 Tube Tester:

• Test Conditions: Va = 250V, Vg = -8.5V
• Average 100%: Gm = 2200 ; Ia = 10.5 mA
• Test Result: VERY STRONG

Valve #1:

• Section 1: Gm = 2300 ; Ia = 9.8 mA
• Section 2: Gm = 2300 ; Ia = 9.8 mA

Valve #2:

• Section 1: Gm = 2220 ; Ia = 9.4 mA
• Section 2: Gm = 2200 ; Ia = 9.6 mA

Additional Tests Performed:

• Microphonics: Low. Tested and approved for use in hi-fi, including phono stages and guitar amplifiers. Also suitable for V1.
• Output Quality: Excellent – ​​Very strong and stable output, no fluctuations.
  
• Short circuits and GAS: Absent.

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Conditions:

• Condition: NOS - New Old Stock - Tested and in perfect working order. Comes in our custom box for optimal protection.
• Functionality: Fully functional.
• Cosmetic condition: Good – Lettering partially eroded, but still legible. Valve body in good condition. See photos for details.

Manufacturing Code:

JV → two-letter code → production June 1966

Find out why our valves are different →