JJ Electronic 300B power triode

The JJ Electronic 300B is a high-end, directly-heated power triode rated at up to 40 W dissipation, built for audiophiles chasing top-tier sound quality. Famous for its tonal richness, it produces a warm, natural sound with a smooth midrange, deep bass and detailed top end. That 40 W dissipation rating also brings strong efficiency and low distortion, making it well suited to demanding hi-fi use.

JJ Electronic tubes are manufactured in-house in Slovakia under strict quality control - every single tube is individually measured and tested before it goes on sale. The manufacturer's range covers both small-signal preamp triodes/pentodes and high-power output tubes, so a matched, coherent tube set can be put together for a given amplifier kit (e.g. the ELEKIT TU-8400 or TU-8900 series). Before tube rolling, always check the amplifier manufacturer's list of compatible tube types and any bias adjustment that may be required. After installing a new tube, it is worth allowing a few hours of burn-in before making a final judgement on the sound, since the cathode coating and structural elements stabilise during the first hours of operation. For output tubes bought as a pair or quad, the manufacturer typically selects units to a tighter (matched) tolerance, which results in more even current sharing and lower distortion in push-pull circuits - this matched selection is exactly why buying tubes as a factory-matched set, rather than individually, is strongly recommended for push-pull amplifier designs. When swapping a tube, keep the old one until the new one has been tested and confirmed working, so you can quickly fall back to a known-good state if anything goes wrong.

Slovak manufacturer JJ Electronic is one of the most reliable tube makers still actively producing today, with every tube going through strict quality control before it reaches the market.

Package weight: approx. 0,200 kg.