Ray Tubes Select 300B

Ray Tubes Select 300B – a legend reborn

Only the top 4–5% make the cut

The Ray Tubes Select 300B is one of the most revered output valves in high-end audio — deployed as the output stage in single-ended triode amplifiers, where it bears full responsibility for the amplifier's power output. Fewer than 5% of any production batch earn the Select designation. Consequently, this tube delivers a clearly audible improvement over standard new production alternatives, even in amplifiers at the upper end of the market. Tube rolling with the Ray Tubes Select 300B is therefore one of the most impactful upgrades you can make to a valve amplifier.

A legend with a golden history

Introduced in 1938, the 300B powered the sound systems of Hollywood's Golden Age cinemas. It has since become a reference point in high-end audio — valued above all for its low noise floor, long-term reliability, and unmistakable musicality. Furthermore, it remains the output valve of choice for audiophile single-ended amplifier designers worldwide. Ray Tubes brings this classic back to life with contemporary manufacturing methods and a rigorous selection process.

Sound character: lush, vocal, and coherent

The Select 300B excels in the midrange: rich, full-bodied, and warm in character, with a particularly convincing portrayal of vocals from baritone to soprano. Bass is controlled and cohesive — supple and elastic, with just the right amount of body without overwhelming the soundstage. Thereby making this tube an outstanding choice for acoustic music, jazz, and classical repertoire. The treble is smooth and layered, with a natural sparkle that gives strings and female voices a refined, non-fatiguing presence. Moreover, music remains engaging and inviting across extended listening sessions.

Gold pins and long-term reliability

Every tube is hand-selected and features gold pins, offering superior conductivity and oxidation resistance compared to standard materials — thereby ensuring a stable, lasting contact in the valve socket. The Ray Tubes Select 300B arrives in protective packaging with a user handbook covering burn-in guidelines and a certificate of authenticity. The 12-month warranty against manufacturing defects is a rarity for an output valve and reflects Ray Tubes' confidence in the durability of their product.

Specifications

• Tube type: 300B
• Socket: 4-pin
• Power output: 6.6 W
• Amplification factor (µ): 3.85
• Transconductance: 5.5 mA/V
• Internal resistance: 0.7 kΩ
• Max. anode voltage: 480 V
• Max. anode dissipation: 40 W
• Anode current (self-bias): 100 mA
• Anode current (fixed bias): 70 mA
• Filament voltage: 5 V
• Filament current: 1.2 A
• Available as: single, matched pair, or matched quad
• Warranty: 12 months against manufacturing defects

Frequently asked questions

What sets the Ray Tubes Select 300B apart from other new production 300B valves?

Ray Tubes assesses every Select tube individually for sound profile, dynamics, microphonics, gain, and transconductance — supplemented by listening sessions under real-world conditions by experienced audio engineers. Fewer than 5% of the production batch meet these criteria. The Select 300B consequently offers a consistency and sonic quality that standard new production alternatives simply cannot match.

Which amplifiers are compatible with the Ray Tubes Select 300B?

The 300B is a standardised output valve compatible with all 300B valve amplifiers and single-ended triode designs. Ray Tubes provides a comprehensive compatibility list on their website. Feel free to contact us for tailored advice on your specific amplifier.

How long does the Ray Tubes Select 300B need to burn in?

Ray Tubes recommends a burn-in period of approximately 40 hours before the tube reaches its full sonic potential. The sound therefore continues to open up and fill out over the first days of use. Detailed burn-in guidelines are included in the user handbook supplied with every tube.