Original General Electric 6SN7GTB NOS Vacuum Tube with Original Box
In the world of analog audio, finding unused original replacement tubes is becoming increasingly rare. We are proud to offer this Original General Electric 6SN7GTB NOS (New Old Stock) Vacuum Tube, an authentic piece of American electronic engineering that has been exceptionally well preserved over the decades and is ready to bring new life to your Hi-Fi audio equipment.
NOS Condition and Technical Verification
This tube is supplied in its original General Electric box (classic orange and white design). As a NOS (New Old Stock) component, it has never been used in an operating circuit.
To provide complete confidence to our customers, the tube was removed from its original packaging only for diagnostic testing using a Kyoritsu K-119 vacuum tube tester. The test confirmed strong, healthy emission, indicating proper cathode performance and no evidence of vacuum loss (leaks) that can occasionally occur during long-term storage.
Construction Details: The “Coin Base”
As shown in the accompanying photographs, this tube features the distinctive short Bakelite “Coin Base”, a design highly recognized by audiophiles and vintage electronics technicians. This construction is characteristic of later General Electric production, most likely from the late 1960s to the 1970s.
These later-production Coin Base tubes are valued for their excellent thermal stability, very low microphonics, and clean, linear sonic performance, making them a popular choice for high-fidelity audio applications.
The tube also retains its original acid-etched General Electric logo on the glass, an important indicator of authenticity.
Technical Specifications (6SN7GTB Datasheet)
The 6SN7GTB is the most rugged and advanced version of the 6SN7 family, making it an excellent choice for both vintage and modern equipment requiring high-performance operation.
Tube Type: Medium-Mu Twin Triode Vacuum Tube
Base: Octal (8-pin) JEDEC 8BD – Coin Base Construction
Heater: 6.3V AC/DC at 0.6A (11-second controlled warm-up to help extend tube life)
Maximum Plate Voltage: 450 Volts
Plate Dissipation: Up to 5.0 Watts per plate
Nominal Transconductance: 2,600 µmhos (at 250V)
Recommended Applications
A vacuum tube of this quality is ideal for audiophile-grade preamplifier stages, phase inverter stages in classic instrument amplifiers, and especially for single-ended tube headphone amplifiers, where low noise and excellent linearity are essential.
Frequently Asked Questions (FAQs)
What does it mean that this General Electric 6SN7GTB vacuum tube is “NOS”?
NOS stands for New Old Stock. It means the tube was manufactured decades ago but was never sold to an end user or installed in operating equipment. Although vintage, it remains an unused component, preserving its original factory characteristics and performance.
Why is the black base on this tube so short?
It is known as the “Coin Base” design. This short Bakelite base was introduced by General Electric during its later production years. It reduced material usage while providing a compact, robust construction. These Coin Base tubes are highly regarded by vintage audio enthusiasts and technicians for their excellent mechanical stability, low microphonics, and reliable long-term performance.
If the tube is NOS, why was it tested with a Kyoritsu tube tester?
Even NOS (New Old Stock) vacuum tubes can occasionally develop problems during decades of storage, such as loss of vacuum or reduced cathode emission. For this reason, the tube was tested using a Kyoritsu K-119 vacuum tube tester to verify its condition.
This emission test ensures that the tube is not only unused, but also fully functional and ready for service, giving buyers additional confidence in its operating condition.
Does it come with its original packaging?
Yes. As shown in the photos, this tube includes its original General Electric factory box, featuring the brand’s iconic orange and white packaging.
