WE300B Western Electric orig. factory matched Pair Holz Box

WE300B Western Electric factory matched pair – the original tube for your 300B amplifier

Every 300B amplifier owner eventually faces the same question: one of the many replicas, or the original? This factory matched pair gives you the genuine Western Electric WE300B from current US production, built to the original 1938 specifications. Each tube carries an engraved serial number, passes a 72-hour selection process, is paired in the USA and ships in a wooden box.

A pair is exactly what a stereo single-ended amplifier needs – one 300B per channel, from the historic Western Electric 91A cinema amplifier to current designs such as the Fezz Audio Mira Ceti 300B or the Woo Audio WA5 headphone amplifier. Sonically, the WE300B is wonderfully musical: pleasantly open, with clean, well-defined bass and a well-structured soundstage – a presentation that never fatigues and keeps the joy in listening. Fill in the enclosed warranty card and mail it to the USA within 10 days of purchase: this extends the manufacturer warranty from 90 days to a full 5 years.

Typical applications

• Retubing or first-time fitting of stereo SET amplifiers using one 300B per channel
• Upgrading an existing 300B amplifier from a replica to the original
• Channel-matched operation thanks to tight factory pairing
• New audio DIY builds with a properly calculated output transformer

Technical data

Valve type

directly heated power triode for Class-A audio service

Base

UX4 (4-pin)

Heater / filament

5 V / 1.2 A

Average characteristics (plate voltage 300 V, grid −61 V)

plate current 60 mA, amplification factor 3.85, transconductance 5.5 mA/V, plate resistance 700 ohms

Absolute limits (not operating points)

max. plate voltage 450 V, max. plate dissipation 40 W, max. plate current 70 mA with fixed bias or 100 mA with self-bias

Life expectancy

rated by the manufacturer at typically 40,000 hours within published specifications

Burn-in period

approx. 50 to 100 hours to reach full sonic potential

Dimensions

bulb diameter approx. 61 mm, height approx. 140 mm

Scope of delivery

2 valves as a factory matched pair with serial numbers and test cards in a wooden box

Warranty

90-day manufacturer warranty, extendable to 5 years by mailing the enclosed warranty card to the USA within 10 days of purchase

Country of manufacture

USA (Georgia)

Application and design notes

Before retubing, make sure your amplifier is designed for 300B operating conditions and re-adjust the bias after installation where the circuit provides for it. The 300B is directly heated; with AC filament supply, the data sheet recommends returning grid and plate circuits to a center tap on the filament winding. Allow a burn-in period of around 50 to 100 hours before making a final judgement on the sound. Lethal voltages are present inside the amplifier – open the chassis only if you are qualified to do so.

Questions about selection and use

Can you still buy the original Western Electric 300B?

Yes, Western Electric manufactures the WE300B itself again in the USA – to the original 1938 specifications and with engraved serial numbers to prevent counterfeits. This offer is a brand-new factory matched pair from current production, not old stock and not a replica.

Does the current WE300B match vintage NOS examples?

Yes, it is the same tube type from the original maker: according to the manufacturer, the 1938 specifications, original tooling and filament core material from old Western Electric inventory are used. The overall sonic result always also depends on the amplifier, operating point and output transformer.

I want a very musical-sounding 300B – is the WE300B the right choice?

Yes, this is precisely the character the WE300B has been known for over decades: a relaxed, long-listening presentation with fine soundstage layering and well-defined low end that lets you enjoy music for hours without fatigue. Allow the pair around 50 to 100 hours of burn-in to reach its full potential in your own amplifier.