AUDIO VALVES: EL34 6CA7 CV1741 KT77 OUTPUT PENTODE

The EL34 was the 1952 successor to the very successful EL37  with which it shares a high value of mutual conductance of 11.0 mA/V allied to a maximal anode dissipation level of 25W with a sub 1.5% distortion level possible. The EL37 was of pinch construction whereas for the EL34 mullard used the pressed glass foot construction employed on the B9A and B7G miniature valves for this IO based device. 

 When used in push-pull ultra linear configuration is capable of excellent results and low distortion.    The definitive circuits for these valves was given by Mullard's own design labs in the publication Circuits for Audio Amplifiers. Having a tall form glass tubular envelope of approximately 35mm diameter and 100mm length this is a compact punch packing output pentode which found use in many classic valve guitar amplifiers, classic   valve hifi amplifiers  from Leak, Concordant, Dynaco, Tannoy, Decca, Pye, Radford and Rogers to name but a few!    Some current exotica using the EL34 is listed below:-

 Aestetix power supply

ASL aq1006-845 dt

Audio Matiere Accordance

Audio Sculpture Equilibre

CJ Premier 4

Conrad Johnson monobocks

Cornell Plexi 45/50 2003

Dynaco ST70

Elmwood

Germino Club 40

Germino Fillmore

Heritage Colonial 50W

HIWATT DR103 - Custom 100 Head

Hiwatt DR-103 1971

Lectron JH50 power amp

Mad Professor amp

Manley amp

Mrantz 2

Marantz 9

Marshall 1987 head

Marshall 50 watt Bass 1972 (model 1986)

Marshall JMC 2000 DSL 100 watt 2003

Matchless (35 watt Class A)

Matchless Chieftain 1995

Park 75

Randall RT2/50 power amp

Sonic Frontiers amp

THD amp

Two Rock amp

Univalve amp

VOX AC50, AC100 Super DeLuxe

VTL amp

Woo Audio amp