Ray Tubes Reserve KT88

The KT88 has been the output tube of choice for high-power push-pull amplifiers since 1956. Its combination of power capability, linearity, and longevity made it the standard for serious audio amplification from its introduction through the present day. New Old Stock KT88 is increasingly scarce and increasingly expensive. Good new-production alternatives matter.

The Ray Tubes Approach

Ray Tubes was created specifically to supply the audiophile market with new-production tubes built to audio-specific standards — not repurposed industrial tubes or rebranded commodity production. They partner with manufacturers to build tubes to their own specifications, then subject every batch to a QC process that includes electrical testing and listening evaluation by sound engineers. Not a cursory test. A meaningful one.

The Reserve line represents Ray Tubes' higher-performance tier — selected from production for tighter tolerances and more consistent performance than the Select line.

Press Recognition

Ray Tubes is a newer brand without extensive press coverage yet. Our own evaluation of their KT88 and the feedback from customers who have used them in Unison Research, PrimaLuna, and similar amplifiers has been consistently positive — comparable in character to the better NOS options at a fraction of the price.

Specifications

• Type: KT88 beam tetrode
• Application: Output tube, push-pull and triode amplifiers
• Production: New production to Ray Tubes specifications
• Quality control: Electrical testing plus listening evaluation
• Tier: Reserve (higher selection threshold than Select)
• Pricing: Per pair

Questions about matching these to your specific amplifier, or comparing Reserve versus Select for your application? Reach out.