12AX7 / ECC83 HAMMOND by RCA – Long Gray Plates – Square Tilt Getter – Made in USA '50s
AMPLITREX Tested – VERY STRONG – Low Noise & Microphonics
Description:
This 12AX7 / ECC83 branded Hammond and produced by RCA in the United States in the 50s represents one of the most authentic expressions of the American school of the time, characterized by robust construction, high quality materials and great reliability over time.
Hammond production by RCA is particularly appreciated because it was intended for high-end electromechanical organs, where stability and durability were essential. This translates today into selected tubes, often superior to the average of standard production.
The internal structure highlights distinctive elements of great value:
- Long Gray Plates
- Square Tilt Getter
- solid and precise mechanical construction typical of RCA from the 50s
The square tilt getter is a less common configuration, typical of older production runs, associated with excellent vacuum quality and operational longevity.
The valve has been tested in our laboratory with Amplitrex AT-1000 , with a VERY STRONG result, and verified by Low Noise & Microphonics , proving to be perfectly suitable even for sensitive applications.
The aesthetic conditions are consistent with the age , as visible in the photographs: partially present silkscreens and signs of aging, without compromising performance in any way.
Sound Characteristics
This RCA 50's configuration offers a typically warm, full and three-dimensional sound, with an extremely natural musical presentation.
Bass: Deep and rounded, with excellent structure and body. Never intrusive, but always well controlled.
Mids: The real strength: rich, textured, and incredibly expressive. Vocals are present, credible, and nuanced.
Highs: Sweet and refined, never aggressive. Excellent extension with a velvety performance typical of the best vintage RCA productions.
Dynamics: Fluid and natural, with a musical response that prioritizes coherence and musicality over artificial impact.
Soundstage: Wide and well-layered, with excellent instrument separation and realistic depth.
🎧 Use in Hi-Fi Amplifiers
Ideal for:
- tube preamplifiers
- vintage and modern integrated amplifiers
- phono stages (due to low noise)
- quality buffer and line stage
Perfect for systems requiring musicality, naturalness and realistic harmonic reconstruction , with a typically “American” sound signature.
🎸 Use in Music Applications
Also highly appreciated in the instrumental field for:
- guitar amplifiers
- vintage organs and instruments
It offers a warm, progressive and musical response, with a soft and controlled saturation, ideal for those looking for character without harshness.
🎯 Note for audiophiles
This Hammond by RCA from the 1950s represents a very interesting choice for those who want a 12AX7 with authentic vintage character , solid construction and high performance.
The VERY STRONG test on Amplitrex and the Low Noise & Microphonics verification ensure stable and reliable operation, making it suitable even for critical positions in the circuit.
A valve that combines history, construction and musicality , designed for those seeking not only performance, but a true listening experience.
Test Results
Tested on AMPLITREX AT-1000 Tube Tester
Voltage Test: Va = 250V, Vg = -2V
Average 100%: Gm = 1600 ; Ia = 1.2 mA
TEST RESULT: VERY STRONG
Valve:
-
Section 1 : Gm = 1500; Ia = 0.9 mA
-
Section 2 : Gm = 1700 ; Ia = 1.0 mA
Additional Tests Performed:
- Microphonics: Low Noise & Microphonics – Tested and compliant for use in hi-fi systems and guitar amplifiers.
- Output Quality: Excellent – Very strong and stable output, no fluctuations.
- Short circuits and GAS: Absent.
Conditions:
-
Condition: Vintage tubes - Tested and in perfect working order. Shipped in our custom box for optimal protection.
-
Balance: The sections present a coherent balance, fully compatible with use in hi-fi and musical amplifiers, in all applications where absolute symmetry between the sections is not required.
-
Functionality: Fully functional.
-
Aesthetic condition: Fair – Writing almost completely faded. See photos for details.
Manufacturing Code:
-
Unreadable, identifiable by construction features. 1950s
Find out why our valves are different →