12AU7 / ECC82 TELEFUNKEN NOS Matched Pair - Smooth Plates - Made in West Germany

12AU7 ECC82 NOS TELEFUNKEN Matched Pair Smooth Plates Tubes Made in W. Germany

Description:

This matched pair of 12AU7 / ECC82 TELEFUNKEN NOS , produced in West Germany , represents one of the most authoritative expressions of the German construction school.

One tube has a clearly visible Diamond Bottom; on the other the imprint is very light. The smooth-plate internal structure and manufacturing codes are, however, fully consistent with original Telefunken production from Berlin.

The tubes are authentic NOS (New Old Stock) , selected and matched in our laboratory, with tests performed on Amplitrex AT-1000 .

Rated Low Noise & Microphonics , they are also suitable for sensitive circuit positions.

Sound Characteristics

Bass: Controlled, linear, and well-structured. The low range is precise and never intrusive, with excellent articulation and rhythmic coherence.

Mids: Neutral, refined, and highly transparent. Voices emerge naturally and cleanly, without any pronounced coloration. Acoustic instruments and strings are defined and harmonically complete.

Highs: Extended, airy, and finely detailed. The upper end is clean and well-controlled, with a fine texture that favors prolonged listening even on high-resolution systems.

Dynamics: Balanced and composed. Excellent microdynamics and linear transient response, with consistently predictable and consistent behavior.

Soundstage: Stable, well-organized, and three-dimensional soundstage. Precise separation of sound planes and sharp focus of the central image.

🎧 Use in Hi-Fi Amplifiers

Ideal for:

• medium-high and high quality line preamplifiers
• driver stages and phase inverters
• integrated amplifiers and power amplifiers that require stability and silence

Particularly suitable for systems oriented towards transparency, neutrality and timbral correctness.

🎸 Use in Music Applications

Also appreciated in:

• instrument amplifiers
• studio equipment
• sensitive entry positions

They offer clarity, control and balanced harmonic response, while maintaining silence and operational stability.

🎯 Note for audiophiles and technicians

• Original Telefunken production – Made in W. Germany
  
• Smooth Plates
• NOS – New Old Stock
• Low Noise & Microphonics
• Tested and matched on Amplitrex AT-1000

A pair that embodies the Telefunken character: precision, balance, and consistency over time. Designed for those seeking a technically solid, musically neutral, and historically significant 12AU7, in true Vacuum Tubes Treasures style.

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 = 2100 ; Ia = 10.0 mA
• Section 2: Gm = 2000 ; Ia = 8.6 mA

Valve #2:

• Section 1: Gm = 2000 ; Ia = 8.6 mA
• Section 2: Gm = 2000 ; Ia = 8.2 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.

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 – Labeling partially eroded, but still legible. Tube body in good condition. One tube has a clearly visible Diamond Bottom; on the other, the imprint is very light. The smooth-plate internal structure and manufacturing codes are, however, fully consistent with original Telefunken production from Berlin. See photos for details.

Manufacturing Code:

• B1203527 - B → Berlin plant - 1 / 2 → day of production (12) - 0 → tenth of the month - 3 → last digit of the year (1963) - 5 → last digit of the month - 27 → internal serial / batch number
• B fr 27 → B → Berlin - fr → December 1968 - 27 → Internal serial number

The codes indicate distinct production batches, while maintaining the same smooth-plate internal structure and authentic diamond bottom. Both tubes feature consistent construction and characteristics typical of Telefunken West Germany production.

Find out why our valves are different →