YJ7591 Product Image

The YJ7591 is a specialized, current-limiting/voltage-conditioning adapter for use in most amplifiers that use 7591 output tubes. Only the triode version will provide a noticeable power reduction. The ground wire connects to chassis-ground for cathode-biased amplifiers. All Yellow Jackets® converters come with JJ Brand EL84/6BQ5 vacuum tubes.

  • Converts most audio amplifiers with 7591s to EL84s without modification or rebiasing.
  • One year warranty for manufacturer defects
  • Safe for all common amplifiers and transformers.

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
Class AB to Class A operation
Class AB Pentode to Class A Triode
Drops Output Power
Product Manual
Additional Documents
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