(1) Tested Zenith 6KT8 Tube High Mu Triode Sharp Cutoff Pentode Tube

(1) Tested Sylvania 10GN8 Tube Date Code 1F High Mu Triode Sharp Cutoff Pentode

(1) Tested Sharp Japan 17JZ8 Tube Date Code 8-7 Medium Mu Triode Power Pentode

(1) Tested Tung-Sol 6AW8A Tube Tung Sol 6AW8 A High Mu Triode Cut Off Pentode

(1) Tested RCA 6AU8 Tube Medium Mu Triode Sharp Cut Off Pentode Tube

(1) Tested RCA 6JE8 Tube with Box Code AV High Mu Triode Sharp Cutoff Pentode

(1) Tested Philco 6JE8 Tube Date Code EBF High Mu Triode Sharp Cutoff Pentode

(1) Tested Very Strong RCA 6AG9 Tube RCA Medium Mu Triode Sharp Cutoff Pentode