(!!!) (#1 - U52=5U4G - Best Single - Best Sound) U52=5U4G GEC brown base "D" getter NOS 1950's (54/40 and 55/40) (#3)

$ 398.88

1 tube) U52=5U4G GEC black plates - brown base "D" getter halo NOS 1950's original box

date code "LM" - tube was factory sealed in plastic, cut open to test 

1 section) 54/40 

1 section) 55/40

Amplitrex Tested: 120ma current through plates (below 42ma V drop is very good)

Diode #1 Forward Voltage 418V, Reverse 26V drop

Diode #2 Forward Voltage 418V, Reverse 27V drop

"Aduana perfumeria circulacion" stamp on glass (Spain - customs / export tax label)

U52 are best sounding 5U4G ever made

the only 5U4G substitute that sonically compares to the U52 is the 274A or 274B Western Electric 


Recommended for

- WA6-SE (Special Edition) Headphone Amplifier

- SET amps

- Wright Sound SET

- Audio Note P4 Balanced mono amps

- Dared MCP7 preamp with phono

- Singlepower

- Modwright Transporter

- Donald North Audio






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