(!!!!!) (Best Pair) 5691 RCA red base black plates NOS 1956-1957 (2.2/2.3ma and 2.1/2.4ma)
(!!!!) (Best Single 1960's) 5691 RCA Red Base branded GE Black Plates NOS 1960's rebranded in 1970's (2.4/2.6ma)
(!!!!) (Recommended Single) 5692 RCA RED BASE black plates used/good 1953 (7/8ma) (Schiit Saga+)
(!!!) (Best Value Pair) 5691 RCA Red Base gray plates rebranded GE NOS 1960's (2.1/1.8ma and
(!!!) (Recommended Pair) 5691 RCA red base gray plates 1968-1974 (2.2/2.4ma and 2.1/2.3ma)
(!!!) (Recommended Single) 5691 RCA red base black plates NOS 1957 (2.0/2.1ma)
5691 RCA Red Base Black Plates used 1948 (2.2/2.4ma) (Gm=62% and 75%)