Vintage Tung-Sol 6550 Blackplate Vacuum Tube - Metal Collar - 1957 Date Code (Untested)
Brand: Tung-Sol Model: 6550 Blackplate (Solid Plate, Metal Collar Base) Year: 1957 Condition: Very Good (Cosmetic condition of glass, base, and pins)
Description
Offered by The Guitar Armory
Up for sale is a holy-grail piece of American audio history: an original vintage Tung-Sol 6550 Blackplate power tube, manufactured during the absolute golden era of US tube production.
This is the highly coveted, early-production variant featuring the rugged nickel/steel wrap-around base collar and solid, smooth carbonized matte-black plates—lacking the later three-hole grey-plate design. This specific tube was pulled from a meticulously kept private estate collection.
Authenticity & Date Code:
- Manufacturer Code: 322 (Authentic Tung-Sol USA)
- Date Code: 5721 (Manufactured the 21st week of 1957—late May)
- Full Stamped Code: 3225721-3
Physical Condition:
- Glass envelope is structurally sound with no cracks.
- The original top getter flashing is bright, highly reflective, and completely intact (no milky white air leakage).
- The center plastic octal alignment pin is intact.
- Internal plate structures and support rods are straight and secure.
Testing & Shop Policy: Because this tube came directly out of a large collection and we do not currently have a calibrated mutual conductance tube tester on-site at the shop, this tube is being sold As-Is / Untested. Returns will be permitted up to 7 days from delivery. Tube collection acquired from vintage pro audio service center for MacIntosh amps. Buy with confidence.
Thanks for looking! This won’t last. Make it yours!
This item is sold As-Described
This item is sold As-Described and cannot be returned unless it arrives in a condition different from how it was described or photographed. Items must be returned in original, as-shipped condition with all original packaging.Learn More.
| Listed | 3 days ago |
|---|---|
| Condition | Very Good (Used) Very Good items may show a few slight marks or scratches but are fully functional and in overall great shape.Learn more |
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