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Philips ECC81 12AT7 Foil D-getter Matched Pair - Holland 1960 TK2 - Same code

Philips ECC81 12AT7 Foil D-getter Matched Pair - Holland 1960 TK2 - Same code

Regular price $184.50 USD
Regular price Sale price $184.50 USD
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Product Summary

The "textbook Heerlen sound" has been referenced in several Soundlumia listings of Amperex Holland 12AT7/ECC81 tubes, and many tube enthusiasts asked what that all means. So this is the answer: the late 1950s and very early 1960s tone, the beginning of over a decade's excellence in sound, the classic tonal template for all the great (and greater) Amperex/Philips/Valvo/Miniwatt tubes to be made in the years to come, the timeless Philips radio tone that many of us grew up listening to. 

Sound Characteristics 

The most distinctive sound feature of the Heerlen ECC81's is the transparent, natural and expansive midrange presentation, with a slight touch of warmth that illuminates your music. Every piece of music you play through these tubes sounds like from a vinyl record, whether your sound source is phono or not. The sound stage is spacious, deep and structured. Bass is incredibly deep but well controlled and feels as accurate as on the high end German ECC83's (Siemens, Telefunken, Valvo etc.) Thanks to the very rare foil d-getter on this pair, you get with fast response (as in the solid-state fast), overwhelming detail in sound and the realistic bass.

Professional Tube Testing 

Both tubes tested Super Strong NOS  (120%+ nominal mutual conductance) on a reliable recently calibrated Mercury 2000 tube tester with the following results (mutual conductance both in uMhos and in percentage of nominal):

Tube 1: 3,500/3,600 (100%/103%)
Tube 2: 3,580/3,820 (102%/109%)

Good tubes start at 2,000 and new tubes (incl. NOS/NIB) 3,500, and the Mercury 2000's rated mutual conductance (nominal) for new tubes is 3,500. 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 tube's ability to amplify sound, so the higher these numbers the stronger. 

Appearance & cosmetic condition

Besides the world-class sound characteristics, we still treasure this pair for its near pristine cosmetic condition given the tubes' age - nearly 100% of the paint is still intact on both tubes, and the Heerlen date codes are perfectly visible on both tubes: 

Tk2 ⊿6K (Tk = ECC81, ⊿ = Heerlen, Holland, 6 = 1966, K = November)



This pair of tubes will be packaged in new white boxes.

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