AUDIO VALVES: EZ81 U709 UU12 CV5072 6CA4 RECTIFIER


The EZ81 was introduced by Mullard as a high current B9A rectifier, the low power rectifier offered by Mullard was the 90 mA EZ80. Prior to the EZ81 Mullard designs used the GZ34.    in use the maximum reservoir capacitor would be limited to 50 µF and to prevent damage by excess current an effective series resistance of 230 Ohms is used.  The thin glass tube envelope is 19 mm in diameter and, excluding the B9A base pins, is 70 mm tall.    The EZ81 saw much use in classic hifi and classic guitar amplifier designed including such exotics as:-

Bogen DB230

Cary SLP90

Concert Fidelity Pre-amp

Marshall EL84 guitar amp

Reinhardt SVT-18 guitar amp

Wright Sound phono stage