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1x Telefunken EF804s ◇ on Bottom - Berlin 1955 - NOS

1x Telefunken EF804s ◇ on Bottom - Berlin 1955 - NOS

Regular price $154.00 USD
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Product Summary

Model: 1955 Telefunken EF804S (Made in Germany)

Soundlumia Tube Sound Rating9.5/10 - Outstanding 

Early 1960s Ulm, Germany production - Unparalleled sound characteristics and superb build quality - True holographic sound stage with layered details and ultra clarity

Date codes: B as 01 (B = Berlin, West Germany, as = August 1963, 01 = internal #)

GM (Mutual Conductance) test result: 100% of NOS/NEW

Silkscreen: 90% - 100%

Packaging: New white boxes.

Professional Tube Testing

NO shorts, leakage or gas. NO noise or microphonics.

This tube tested Near NOS (90%+ mutual conductance value for NOS/NEW) on a reliable Mercury 2000 tube tester with the following result (mutual conductance both in uMhos and in percentage of NOS/NEW value): 


Good tubes start at 1,200 and new tubes (incl. NOS/NIB) 2,500, and the Mercury 2000's rated mutual conductance for new EF86 tube is 2,500. Test result can also be seen in the pictures. In case you wonder what all these numbers mean to your sound experience, it's actually quite straightforward: mutual conductance directly translates to a tube's ability to amplify sound, so the higher the numbers the better. 
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