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Tesla

Tesla ECC88 6DJ8 Tubes Matched Pair - Czechoslovakia 1969 - Same code "FG" - NOS

Tesla ECC88 6DJ8 Tubes Matched Pair - Czechoslovakia 1969 - Same code "FG" - NOS

Regular price $86.50 USD
Regular price Sale price $86.50 USD
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Product Summary

Whether you're looking to try something totally new and exotic or you want to find the best E88CC tube sound at a budget price, these Telsa steel pins made in the original Czechoslovakia factory are absolutely a stunner. They are easily the best bang for your buck E88CC tubes in any price range, and you get the sound qualities close to those of the top end German/Dutch E88CC tubes. 

Sound Qualities 

Many listeners find these tube sound very much like Telefunken E88CC's and that's a true statement. They certainly share the most lovely sonic features distinctively known to the supreme commander: liquid, euphonic, detailed with great sound clarity. The top end is very smooth and airy with no brightness or harshness non whatsoever and reminds one of the magical non-fatiguing extension of highs on Siemens E88CC's. Midrange presentation on these tubes is transparent and expansive, similar to the famed Amperex Holland/Philips mids from Heerlen and feels even more intimate than on Telefunken's. The bass control on these tubes truly sets them apart: deep, clean and accurate without being too punchy. 

Professional Sound Evaluation

The pair sounded terrific in our professional studio setup for monitoring. 

 - Input: Cambridge Audio CXC V2 dedicated CD transport + Schiit Audio Bifrost 2 Multibit DAC
 - Amplification: Liquid Platinum Tube Amplifier by Alex Cavalli 
 - Output: Focal Clear MG Pro open-back headphones

Our full tube sound review was written 100% based on the actual listening experience while these tubes were running in the system described above.

Professional Tube Testing 

Both tubes tested Strong NOS (110%+ nominal mutual conductance) and tightly matched on a reliable and recently calibrated Mercury 2000 tube tester with the following result (mutual conductance in uMhos and percentage of nominal):

Tube 1: 15,000/14,500 (120%/116%)
Tube 2: 14,200/14,500 (114%/116%)

Good tubes start around 7000 and new tubes (incl. NOS/NIB) 12,500 - 13,000, and Mercury 2000's rated mutual conductance (nominal) for new tubes is 12,500. Test result can also be seen in the pictures. In case you wonder what all these numbers would mean to your sound experience, it's actually quite straightforward: mutual conductance directly translates to tube's ability to amplify sound so the higher the numbers the stronger. 

Appearance & cosmetic condition

Beside the world-class sound characteristics, we treasure this quad also because of their excellent condition of inscriptions - nearly 100% of the paint and lettering is well preserved and the IDENTICAL Tesla Czechoslovakia date codes are also perfectly visible on all tubes: 

FG (March, 1969)

Tesla tube date codes can be looked up here: https://tubes-store.com/article_info.php?articles_id=5. 
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