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6BX7 to 12B4A tube adapter for Topaz amplifier
Topaz 6BX7 to 12B4A adapter - top view with 12B4A tubes
Product Status

Adapter upgrade from 6BX7 to 2 x 12B4A triodes

  • lowers the overall gain of amplifier by about 5 or 6 dbs
  • lowers the noise floor by the same amount - this lowers the dynamic floor
  • gives a greater sense of uncompressed music - Dynamic bandwidth is greater
  • gives more precise channel balance - better 3D effect
  • more silence between notes from speakers
  • Adapter consist of a cast aluminum black case
  • 8 pin male socket - plugs into 6BX7 socket
  • 2 x 9-pin Teflon sockets for the 12B4As
  • 2 x 12B4A NOS GE triode tubes
  • PCB board where components are mounted
  • machined deep red plexiglass cover
Price (USD)
$ 435
Price (CAD)
$ 600