(1) Tested RCA 6AU6 Tube RCA Sharp Cut Off Pentode Vintage Tube (c)

(1) Tested RCA 6AU6 Tube RCA Sharp Cut Off Pentode Vintage Tube (b)

(1) Tested RCA 6AU6 Tube Date Code 504 RCA 6AU6 Sharp Cut Off Pentode Tube

(1) Tested RCA 6AU6 Tube RCA Sharp Cut Off Pentode Vintage Tube (a)

(1) Tested RCA 6AU6 Tube Date Code 352 RCA 6AU6 Sharp Cut Off Pentode Tube

(1) Tested Sylvania 6AU6 Tube Sylvania Sharp Cut Off Pentode Tube

(1) Tested Admiral 6AU6 Tube Date Code 939 6AU6 Sharp Cut Off Pentode

(1) Tested Westinghouse 6AU6 Tube Date Code 5R30 Sharp Cut Off Pentode Tube