YJUni Product Image

The YJUni is a simple pin-converting adapter for use in most amps with 6V6 or similar based tubes like 6F6, 6G6, 6K6, 6Y6, etc. The YJUni is shorter than standard Yellow Jackets®. It is designed for use in lower power output amps (20 watts or less) when no power reduction is desired. If your amp is cathode-biased, then no bias adjustment is needed. If your amp is fixed biased, then the bias should be adjusted just as it would be according to the standard biasing instructions included with the amp. All Yellow Jackets® converters come with JJ Brand EL84/6BQ5 vacuum tubes.

  • Converts pin configuration from 9-pin to 8-pin to allow certain 6V6, 6K6 and similar low-voltage circuits to use EL84 tubes.
  • One year warranty for manufacturer defects
  • Safe for all common amplifiers and transformers.
  • Great for adapting tube-testers to test EL84 tubes.
  • Perfect for THD UniValve, BiValve-30 and Flexi-50 amplifiers.

The Yellow Jackets® pentode versions provide more bite and attitude, while the triode versions provide greater power reduction and more linearity. If you are looking for power reduction and response with more bite and attitude, choose the pentode version. If you're looking for maximum power reduction and want to tame the response of your amp, choose the triode version.

Standard Version
Triode Version
Pin config from 8-pin to 9-pin
Pin config from 8-pin pentode to 9-pin triode
Drops Output Power
Does not drop power
Product Manual
Additional Documents
Select a Yellow Jacket® below to see product details.