(2) RCA 5691 Red Base Black Plate Audio Tubes. I tested them today using my recently calibrated TV-7D/U and with minimum of 32/32 they tested strong at 51/58 and 54/51. $7.45 shipping
1956 5691 RCA GE Tube Black Plate Red Base TV7 Test NOS 5691-1
5691 RCA Tube. Made In USA. Triode 1 NOS: 51/ 32 Baseline. Triode 2 NOS: 52/ 32 Baseline. GE Label Manufactured in September of 1956. NOS tubes fall within the GM range published in the RCA Receiving Tube Manual; variation above/below average is normal.
RCA (Sylvania label) 5691 Red Base Black Plate NOS Tube (balanced and strong)
The box is in rough shape, but the tube is great. It feature black plates, support rods, and a third mica level. The TV-7 lists the minimum as 32, which puts NOS spec around 49. This tube tests very well balanced at 52.2/54.1.
2 RCA 5691 Vacuum Tubes / BOGEY STRONG/ Grey Plates /DD / RED / Amplitrex Tested
One pair of RCA 5691 vacuum tubes. Tested on Amplitrex computerized tube tester analyzer. Tested on Amplitrex tube tester where spec (nominal) values are 1600 micromhos / 2.3 mA. Double DD double D’s getter.
RCA 5691 Red Base Vacuum Tube – Tested Strong
Offered is a genuine RCA 5691 Red Base vacuum tube, proudly made in the U.S.A. The 5691 is the premium, ruggedized long-life version of the 6SL7GT and is highly sought after by audiophiles, vintage hi-fi enthusiasts, and collectors for its exceptional reliability and musical performance. This tube has been tested strong and is ready for use. * Brand: RCA * Tube Type: 5691 * Premium 6SL7GT Equivalent * Genuine Red Micanol Base * Made in U.S.A.
Pair of RCA (GE lbl) 5691 NOS Gray Plate Vacuum Tubes – 6% matched
Nice pair of RCA 5691 Special Red tubes, labeled for GE, with original boxes. Gm matched to about 6% difference on the Amplitrex AT1000. Gray plates, micanol bases, multiple support rods, thick glass, triple micas, and double getters all make for a bulletproof tube.
1 NOS RCA 5691 Vacuum Tube 6SL7 Red Base Triple Mica Black Plates DD Getter
TESTED 52/32 and 51/32 where 32 IS 65% this tube tested 103-105%. Plate current was 5.8 and 5.7.
5691 RCA Red Base
Nos Not tested
NOS NIB MILITARY SPEC RCA RED BASE 5691 6SL7 BLACK PLATE TUBES!
NOS NIB RCA 5691 SPECIAL RED BASE TUBE. PHONO GRADE & RCA CLAIMS A 10,000 HOUR LIFE! TRANSCONDUCTANCE MATCHED PER TUBE PER TRIODE.