SVETLANA TECHNICAL DATA EL34/6CA7 High Performance Audio Power Characteristics T Pentode he Svetlana™ EL34 is a glass envelope power pentode having a plate dissipation rating of 25 Watts with convection cooling. It is intended for audio frequency power amplification service in either pentode, ultralinear or triode connection and single or push-pull/parallel applications. The Svetlana EL34 has an indirectly-heated oxide cathode, which may be DC operated for the absolute best hum/noise per.