6C33CB Single Ended


6c33cb is an electronic tube originating from USSR or today’s Russia. Initially it was invented by the Russian Army and it was kept as a tightly guarded army secret. In 1976 certain Russian pilot navigating famous Russian MIG – 25 Jet Plane deserted Russian Army by landing this plane on Japanese soil.As the MIG – 25 plane was the latest technological invention of that time, japanese engineers were surprised to find electron tubes inside the plane. Russian MIG engineers considered the smallest details. Silicon-based semiconductors cannot tolerate the EMI burst from Atom bomb,
but tubes are fairly immune to this phenomena. Japanese audiophiles were excited by the discovery of this particular electron tube. Soon the 6C33C gained popularity in production of OTL amplifiers. In this way wider market became available and Russia had started exporting them throughout the World. Frame is hand made from oak-wood, rest from messing. I did not make an attempt to weigh it, certainly it is not an object that can be lifted and moved around at one’s ease. In Single-Ended amplifiers the main trouble is the small output power, meaning that speakers of higher sensitivity are a must. In case of 6c33c-b there is no need for sensitive speakers as the amplifiers has more than enough power to generate realistic sound levels.


  • 64 step attenuator
  • Relay selector for 3 input
  • Silver wiring
  • 6H6 ; 6C33CB ; AZ1 tubes
  • C- core output transformer
  • Fix bias
  • Mundorf / MKP capacitors
  • 60 sec turn on HV timing
  • Point to point wiring
  • 14W / 8Ohm
  • 0dB feedback