Groove Tubes 5U4

Common to medium powered amps like the earlier Fender Super Reverbs and Bandmasters. May be used replaced a 5Y3 for improved dynamics and power. Also, some players have replaced their 5AR4 with the 5U4 in their Vox AC30 amps to reduce heat and extend the life of the power tubes, Groove Tubes recommendeds this as a stability enhancer as long as you can live with the slightly lower power. The GT-5U4 is the factory selected rectifier for the Mesa Dual and Triple rectifier series