- vacuum tubes
Dates of manufacture:
The EL34 is an audio power pentode vacuum tube. It was first made in the 1950s by Philips and later became popular after it was used in Marshall guitar amplifiers in the 1960s. Lately it is made in Russia, China, and Slovakia. In the USA these tubes might be labelled 6CA7 (although some 6CA7 tubes are beam-power tetrodes, not pentodes).