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Quad 6550


Vintage RCA USA 6550 Tubes Quad Set

$99.00


Brand New Matched Quad (4) Genalex Gold Lion Reissue KT88 / 6550 Vacuum Tubes

$176.14


Quad SED Svetlana Winged C 6550C KT88 Tubes Dimpled St. Petersburg Test Great

$135.00


New JJ Electronic OEM KT88 Tubes Valves, Matched Quad KT-88 6550 KT 88

$109.99


Factory Matched Quad Tube Amp Doctor TAD 6550 6550A KT88 - GE 6550A Remake

$180.00


Brand New Current Matched Quad Svetlana 6550 / 6550C (KT88) Reissue Vacuum Tubes

$129.59


Quad Set (4) original Svetlana Electron 6550C, Made in Russia, 9920.

$145.90


New Premium Select NessTone 6550 Power Tube Matched Quad - Big, Clean Warm Bass

$89.99


SOVTEK Factory Platinum Matched QUAD FOUR 6550WE 6550 tubes 24 Hr Burn-in

$112.95


Matched Quads (4 tubes) Tung Sol 6550 Reissue amp tubes, BRAND NEW

$124.42


4pcs Matched Quad New Tested Psvane HiFi KT88 6550 Vacuum Tubes

$105.00


New Current Matched Quad (4) Psvane KT88 (6550) HiFi Series Vacuum Tubes Hi-Fi

$124.95


New Plate Current Matched Quad (4) Tung-Sol Reissue 6550 KT88 Coke Bottle Tubes

$131.16


Matched Quad (4) original Svetlana SED 6550C, AT1000 Tested, mid-1990s

$294.00


KT88 Matched Quad Groove Tube (4 Matching Tubes) KT90 KT120 GT-KT88 6550

$134.99


Amplitrex AT1000 Super Gold Matched QUAD GE NOS 6550 6550A USA - For ARC, CJ

$525.00


New Current Matched Quad (4) JJ Electronic 6550 Vacuum Tubes

$135.95


QUAD of General Electric GE 6550A tubes ~ test NOS...OUTSTANDING!

$610.00


Ruby Power Vacuum Tube, 6550A-STR, Matched Quad

$147.95


Tung Sol 6550 Cryo Matched Quad (4) - KT88

$179.99


Matched Quads Svetlana 6550 6550C amp tubes, BRAND NEW

$123.21


Factory Matched QUAD Svetlana KT88SV 6550 KT88 - For Tube Amplifiers

$160.00


6550 Electro Harmonix Cryo Matched Quad (4) KT88

$149.99


MATCHED QUAD - GENALEX GOLD LION KT88 RE-ISSUE VACUUM TUBES - KT88 6550

$174.95


Quad of Tung-Sol (GE label) 6550 KT88 NOS NIB Solid Gray Plate 1961 Vacuum Tubes

$1,200.00


NIB new ElectroHarmonix 6550 KT88 vacuum tube $27ea; matched pair quad available

$27.00


Mullard KT88 Cryo Treated and Matched Quad - (4) 6550 KT90

$179.99


Electro Harmonix Factory Plat Matched 6550 6550EH Vacuum Tubes QUAD 24hr Burn-in

$119.95


4x NEW Ruby 6550A-STR 6550ASTR Vacuum Tubes, Matched Quad TESTED

$143.75


Quad of Sovtek 6550WE Power Vacuum Tube

$111.92


Vintage 1968 TUNG-SOL 6550 Vacuum Tubes - Matched QUAD (Date/Strenght) - KT88 ?

$695.00


MATCHED QUAD - SVETLANA 6550 / 6550C (KT88) VACUUM TUBES - CURRENT MATCHED!

$124.50


Factory Matched QUAD Tung-Sol Tungsol 6550 KT88 - For Tube Amplifiers

$155.00


Tung Sol KT120 Cryo Matched Quad (4) - 6550 / KT88

$199.99


Factory Matched Quad Tube Amp Doctor TAD KT88 6550 For Tube Amplifiers Citation

$199.00


Quad of Telefunken Black Diamond 6550

$284.00


Valve Art Power Vacuum Tube, 6550A, Matched Quad

$115.85


Quad of JJ 6550 Power Vacuum Tube

$139.92


6550 Tubes Tung-Sol reissue platinum matched quad(4) pcs.

$169.90


Quad of Tung-Sol 6550 New Production Power Vacuum Tube

$139.92


Ruby Tubes 6550ASTR Quartet Matched

$163.44