(!) (slightly microphonic single) 12AU7 Hitachi JAPAN branded IEC Mullard NOS ribbed plates 1968 (9.4/11ma) Title: 12AU7 Hitachi JAPAN branded IEC Mullard NOS ribbed plates 1968

1 slightly microphonic low noise tube) 12AU7 Hitachi JAPAN branded IEC Mullard NOS ribbed plates 1968 in white box

1 section) 9.4ma Gm=1900

1 section) 11.0ma Gm=2100

Amplitrex Test Data

Good Ma range 8-10ma

Good Gm range 1800-2200