Skip to product information
1 of 15


Mullard 12AU7 Long Plate Goal Post Square Getter Matched Pair Blackburn 1957 K61

Mullard 12AU7 Long Plate Goal Post Square Getter Matched Pair Blackburn 1957 K61

Regular price $638.00 USD
Regular price Sale price $638.00 USD
Sale Sold out
Shipping calculated at checkout.
Product Summary

No other tubes can deliver vocals like the Blackburn Mullard's, and that's a fact. These special ECC82 tubes, with the rare goal post square getter and 17mm long plates, carrying the unmistakable vintage sound signature of the very early Blackburn K61 (1st generation of ECC82 long plates) production, are extremely hard to find today and shouldn't be ignored by critical listeners and tube enthusiasts. 

Sound Characteristics

The overall tonality of Mullard ECC82 tubes is warm and lively with a very spacious sound stage. "Like a warm British jacket of the finest tweed, these glorious tubes have an attractive sweet warmth in their midrange and lower regions."  This is how the experts on describe the sound signature of British-made Mullard tubes. The top end is silky and pleasant and doesn't get rolled off. They retain a fine sense of "air" at the top, and the upper midrange is smooth and liquid. These tubes reproduce the human voice, especially female voices, with haunting realism. The British made Mullard tubes are also known to have an attractive sparkle at the top with rich we know where that "warm British jacket" comes from!

Professional Tube Testing

Both tubes tested Near NOS (90%+ nominal mutual conductance) and tightly matched 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: 2,950/2,900 (98%/97%)
Tube 2: 2,980/3,050 (99%/102%)

Good tubes start at 2000 and new tubes (incl. NOS/NIB) 3,000 - 3,100, and the Mercury 2000's rated mutual conductance (nominal) for new tubes is 3,000. 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

This tube is in pristine cosmetic condition with nearly 100% of the paint and lettering well retained. The Blackburn date code etched on glass is also perfectly: 

K61 B7D (K61 = ECC82 long plates production gen #1, B = Blackburn, 7 = 1957, D = April)
K61 B7J (K61 = ECC82 long plates production gen #1, B = Blackburn, 7 = 1957, J = October)


This pair of tubes will be packaged in the NEW Mullard reproduction tube boxes.
View full details