Western Electric 300B 1988 TESTED NOS Matched Pair DHT Vacuum Tube HI FI pair

Western Electric 300B – 1988NOS – Original Boxes – 100% Ia Matched Pair

60.0 mA / 60.0 mA – 100.0% Ia Matching – Professionally Tested

For sale is an exceptional pair of genuine Western Electric 300B directly heated power triodes, manufactured in the USA and preserved in NOS – New Old Stock, never used condition.

Both tubes are supplied with their original Western Electric boxes and have been professionally tested under identical operating conditions using a Metrix U61B.

Exceptional electrical matching

The two tubes measured exactly the same plate current:

• B30001: 60.0 mA
• B30002: 60.0 mA
• Ia Matching: 100.0%
• Plate-current spread: 0 mA

This is therefore a 100% matched pair in plate current at the measured operating point.

The test results are documented in the photographs included with the listing.

Identification

Both tubes carry the original gold Western Electric markings:

WESTERN ELECTRIC – 300B – MADE IN U.S.A. 8813

The original boxes are marked:

100792522 / 300B-ET / 5-88

The 5-88 marking indicates May 1988.

Main characteristics

• Manufacturer: Western Electric
• Model: 300B
• Country of manufacture: USA
• Year: 1988
• Quantity: 2 tubes
• Configuration: matched pair
• Condition: NOS – never used
• Type: directly heated power triode
• Construction: traditional single-plate construction
• Base: American 4-pin
• Heater: 5.0 V
• Original Western Electric boxes: included
• Individual identification: B30001 / B30002

Professional test – Metrix U61B

Both tubes were tested under exactly the same conditions.

Metrix test setup:

• Heater: 5.0 V
• Plate voltage: 260 V
• Grid bias: -50 V
• Meter range: 100 mA
• Measured plate current: 60.0 mA / 60.0 mA

Western Electric nominal reference operating point used for comparison:

300 V / -61 V / approximately 60 mA

The Metrix operating point was selected to obtain the corresponding nominal plate-current region while remaining within the available test configuration.

Measured results

B30001

• Ia: 60.0 mA
• Calculated plate dissipation: 15.60 W

B30002

• Ia: 60.0 mA
• Calculated plate dissipation: 15.60 W

Matching result

60.0 mA / 60.0 mA

100.0% Ia MATCHING

Both tubes therefore show identical plate current at the tested operating point.

Why this pair is special

Original vintage Western Electric 300B tubes are among the most desirable directly heated triodes for high-end single-ended tube amplification.

This pair combines several particularly desirable characteristics:

• genuine Western Electric USA production
• 1988 manufacture
• NOS, never used condition
• two original Western Electric boxes
• visually consistent pair
• professionally tested
• identical 60.0 mA / 60.0 mA plate current
• documented 100.0% Ia matching

The combination of condition, provenance, original packaging and matching test results makes this pair particularly attractive both for serious audio use and collection.

The photographs show the exact two tubes offered for sale, including their glass envelopes, bases, pins, original markings, internal construction, boxes and test documentation.

Shipping

The tubes will be packed with particular care using professional protective materials suitable for fragile vintage vacuum tubes.

Orders are normally dispatched within 1–2 business days after payment confirmation.

All shipments are fully tracked and handled by UPS, DHL or BRT, depending on destination, service availability and, whenever possible, the buyer’s preference.

For orders with a value above €200, shipping is always insured.

Local pickup is also available in Milan, Italy – postcode 20154.