You don't see NOS / NIB Tung Sol very often. This is a genuine 6X4 -- the original 25mm shinny back plate version. With it's original box, which is slightly yellowed from the 57 ++ years of time... don't settle for cheaper reissues, or copies. GE, Sylvania and RCA also made excellent 6X4 rectifiers. This is a commercial audio tube, so it's exactly what your HiFi, Guitar or boradcast audio came stock with back in the 1950s!
Old tubes sound better (proving the old maxim .. you get what you pay for! )
They have authentic etched - in - glass Tung Sol codes, as well as white Ink markings. See reports in Exhibit A, C,D,E for detailed descriptions for this tube.
The real McCoy, made in the USA during 1950s - 1960s tubes. Tung Sol's were not produced on the same scale as their bigger compeitiors -- the likes of RCA. They are tough to find, so they always sell quickly.
For easy reference, refer to exhibit ( B ). This rectifier is very strong, testing 110% on a Calibrated Jackson 648 at full load, both halves, Projected life on these is beyond excellent!
Tung Sol, unlike the other major competitors (GE, RCA, Sylvania), primarily specialized in Tubes ( and related Lamp) design & manufacture -- in one way or another since inventing the first automotive light around the turn of the century. Audiophiles have long appreciated Tung Sol tubes ... primarily for their 1950s coup --- the design of the 6550 and 5881 post war power tubes. Really the 6550 by Tung Sol ruled HiFi amp land until GE put out a very nice (under appreciated) design in the 1970s. Arguably, though Tung Sol developed and mfr'd the most perfectly made, highest quality tubes this side of the pond. When it came to larger power, pentode / tetrode tubes, only the British made better -- and at much higher cost.
Tung Sol manufactured their tubes in house, and the quality was simply outstanding. Production facilities were actually production laboratories that manufactured these ... a much different method than their larger competition. Tung Sol's quality and innovation maintained well into the 1960s (they made some of the finest Transistors too) -- and business came to a close sometime in the 1970s as they lost their battle to competition, and poor sales in the Solid State era.
Getting back to the unique qualities of Tung Sol designed and produced tubes though.. and the best examples date from the late 1930s thru the early part of the 1960's ...just before mid decade changes. And, just as severalgrey plade designs became prevalent ... Tung Sol tubes are reserved, super quiet and smooth -- very refined .... quiet and steely (but not cold) with an absolutly tons of resolution.
They have musical qualities, but pack allot more punch in the lower mid vocal area than even RCA's or GE could... and they have a far more defined bottom end ... not reaching down as far ... but absolutely no flab ... hitting notes perfectly in percusive harmony, keeping it all real with an errie smoothness.
They feature early tall plate construction. Original box, in which it was stored (shows wear, and foxing, from the many years of dry storage)
I get allot of requests for quality rectifier tubes .... this 6X4 is a great choice. If your equipment can be adapted for the Western Electric 412A, it's even better (at a higher price). For collectors already in love with GE, RCA & Sylvania ... these top quality manufacturers are quite nice -- almost always delivering the goods. If you are looking for the same amazing detail and build quality ... but looking for something refined and different and more rarified... look for these old Tung Sol's.
Pins are straight, shinny & clean.
ALL TUBES Guaranteed NO DOA.
See our excellent feedback on all vintage tubes.
You'll find no other set of tubes this thoroughly tested & inspected.
Will sell quickly, buy now to avoid a bidder's war.
