EL500 / EL504 / 6GB5

The EL500 and EL504 and similar valves including the PL versions or 40 Volt filament, are excellent quality Tetrodes initially designed and used for TV and AM and FM use and Transmission equipment but, subsequently, given their excellent characteristics in Amplification, they have been used in Low Frequency in AUDIO projects, especially in amplifiers for musical instrumentation and, of course, there are various DIY projects.

EQUIVALENCE: EL504 = R169 and EL500 = 6GB5