Audio Glossary

Tube CAD Journal


Copyright  © 1999 GlassWare


The plate resistance of a vacuum tube. It is the impedance that a tube offers a change in plate voltage. It is equal to mu/gm and it is not as constant as we might like, varying as it does with voltage and current. A 12AX7 has a rp of 62 k, whereas a 6DJ8, 3k.