Sylvania 12AU6 NOS Vacuum Tube – Miniature Sharp-Cutoff Pentode

The Sylvania 12AU6 NOS Vacuum Tube is a high-performance miniature pentode originally designed for wideband amplification applications. Its “sharp-cutoff” characteristic makes it ideal for circuits that require linear and stable gain without the compression typical of remote-cutoff tubes.

Common applications of the Sylvania 12AU6 NOS Vacuum Tube:

• Vintage Radios: IF amplifiers and limiters in high-end AM/FM receivers.

• Instrumentation: Used in vintage oscilloscopes and vacuum-tube voltmeters due to its stability and consistency.

• Hi-Fi Audio: Used in the initial stages of boutique preamplifiers and some high-end effects pedals operating with 12V filament voltages.

Brand History: Sylvania (Made in Italy)

Sylvania was a giant in the U.S. electronics industry, but to expand its global market and remain competitive, it outsourced the production of certain models to top European manufacturing plants. This tube, marked “MADE IN ITALY,” comes from the golden era of Italian manufacturing, known for using thicker glass and noble metal alloys in internal components, which helps reduce microphonics.

Technical Specifications of the Sylvania 12AU6 NOS Vacuum Tube

• Type: Sharp-cutoff pentode.

• Heater Voltage: 12.6 V (AC/DC)

• Filament Current: 0.15 A.

• Maximum Plate Voltage: 300 V.

• Plate Dissipation: 3.0 W.

• Transconductance (Gm): 4,500 µmhos (typical).

• Base: 7-pin miniature (B7G).

• Construction: Gray plates, made in Italy.

(FAQ)

Is this Sylvania 12AU6 NOS Vacuum Tube compatible with a 6AU6?
Not directly. Although they share the same 7-pin base and similar functions, the 12AU6 requires a 12.6V heater, while the 6AU6 requires 6.3V. Always check your circuit design before substituting them.

What does “NOS” mean in this Sylvania product?
It stands for New Old Stock. This means the component was manufactured decades ago, has never been used or installed in any equipment, and has been stored in its original factory packaging in preserved condition.

Why is it important that it is made in Italy?
Collectors value European-made tubes (such as those from Italy) for the superior quality of their internal construction, which often translates into a cleaner sound and greater durability compared to standard consumer versions.