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1x Telefunken EF804S Labormuster (Lab Prototypes) - ◇ Bottom - Strong

1x Telefunken EF804S Labormuster (Lab Prototypes) - ◇ Bottom - Strong

Regular price $212.50 USD
Regular price Sale price $212.50 USD
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Product Summary

Model: Telefunken EF804S Labormuster (Made in Germany)

Soundlumia Tube Sound Rating9.5/10 - Outstanding 

Unparalleled sound characteristics and superb build quality - True holographic sound stage with layered details and ultra clarity

GM (Mutual Conductance) test result: 86% of NOS/NEW

Silkscreen: 90% - 100%

PackagingNEW white tube boxes.


Professional Tube Testing

This set was tested and certified by RoeTest V11 Professional Tube Testing System with the following result: 

Tube 1:

Measured transconductance(GM): 1.71 mA/V - 86% (100% = 2.00 mA/V)
Measured plate current(IA): 2.365 mA  - 79% (100% = 3 mA)


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

Curve trace is also included in the original RoeTest report.

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