The JJ GZ34S (5AR4) rectifier valve appears in many famous amps, including the Vox AC30.
Valve rectifiers add a characteristic “sag” to audio signals, a bit like compression, producing better sustain compared to solid state rectified amps. GZ34S valves give your amp a better sound! The JJ GZ34S is a better alternative to replacing your old GZ34 with a solid state rectifier. Old valve rectifiers eventually loose emission, resulting in higher internal impedance and lower output voltage, leading to reduced clean headroom and lower output watts from your amp. We recommend changing your rectifier every couple of years or when you change the output valves. You can keep the old one as a spare for emergencies.
Click here for the JJ GZ34S datasheet
We also stock the Sovtek 5AR4.
We test each rectifier valve  on our suite of vintage, modern, and custom-built valve testers. You can’t buy a better tested or more reliable valve.
Made by JJ Electronic in Slovakia.
Includes our class-leading 180 day warranty.
