EL37 ST fat shape PENTONE Square getter 6L6G KT66 EL35 equivalent holy grail!

Description

The EL37 audio output valve is one of the classic valves and its predecessor was the Mullard EL35.

Mullard also described the EL37 as suitable for use as drivers for large triode push-pull output stages. The EL37 has a high value of mutual conductance compared with the valves it is sensibly equivalent to. At 11.0 mA/V it is almost twice the value of the KT66 and the 6L6.

Audio Magical is glad to show you all EL37 made back those days

Here we have a quartet of Mullard EL37 old logo circa 1955 they are labeled PENTONE  and bear etched code on glass 1282 JO IO etc.

This is the fat shape of the Mullard EL37 hard to come by these days

We offer a set of four pieces all tested with AVO VCM 163

EL37 Mullard has a grid volts of − 13.5 with both Anode and Screen set at 250 V and filament 6.3 V then we got current of 98mA, 98mA, 98mA, 97mA 100% emission and mutual conductance of 11