Check out my perfect feedback on usaudiomart also. Username "soundgood2"2 NOS Sylvania 6SN7GT 6SN7 GT Chrome Dome Vacuum Tubes. Shipping is Flat $10 USPS priority mail to USA only. TESTED ON TRIPLETT 3423 TUBE TESTER; 100% on this tester is 3000. These test above 3000. I HAVE A QUAD OF THESE AVAILABLE. Payment may be made with Paypal friends and family option only, Venmo or Zelle. These are RARE. Here is a background on "Chrome Domes" from www.head-fi.org: "A note on Sylvania Chrome Domes:
The “Chrome Dome” moniker was first applied to particular early 1950s vintage Sylvania 6SN7GTs by tube enthusiasts. The name came about in response to the tube’s appearance – it had a beautifully shiny top getter flashing that nearly reached the bottom of the tube, obscuring almost all of the internal construction from view. "These particular 6SN7GTs are extremely rare, and as time passed, people began applying the “Chrome Dome” moniker to many other Sylvania tubes with top getter flashing. "The following Sylvania tubes are often (incorrectly) called ‘Chrome Domes’:
6SN7GTA
6SN7W
6SN7A
6SN7WGT
6SN7WGTA" “First - there is only ONE Chrome-dome. That is a 1950's 6SN7GT with mid-sized bottle that has the getter almost entirely covering the glass, hence the term 'chrome-dome' was coined to describe it. It is a fabulous sounding tube, close to as good as the '52 Syl, but extremely rare as it had such an awesome rep early on in the tube renaissance that it is pretty much long been absorbed into private collection where very few pop out. Unfortunately, due to the legendary status of the real chrome dome and it's virtual disappearance from the market, sellers have been calling virtually any top getter Sylvania by that name - despite those tubes not having a real chrome-dome at all. There are a few versions of the WGT, and the WGTA has etched markings on tyhe glass. The GTA came in two versions during the 50's with different plates, one hugely good sounding, the other not so great. There are numerous GTB's that range in sound from ok to not so great, but the GTB has nothing to do sonically with the others, and really aren't worth seeking out.” –Robert H. (in personal correspondence)"
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