The older and until now non-existant NOS 1960's EF86 were finest Professional triode-pentode tubes Telefunken or any manufacturer ever made! BEST SOUNDING, BEST MADE and MOST VALUABLE and RARE out of ALL the EF86 Amp and Audio tubes.  You won't find other Extremely RARE Telefunken EF86 Amplitrex Tested tubes around - that's because they are kept and treasured by those who know which the BEST EF86 tubes are!

Based on the NOW available TELEFUNKEN EF86 pentode tube that was already being used in Neumann's small-diaphragm KM56, the U 67 incorporated a new K 67 capsule and transformer-balanced tube circuit along with modern innovations that delivered significant sonic and operational improvements on its predecessor. The U 67 was enthusiastically welcomed by the pro studio community and assumed its place as the large-diaphragm Neumann workhorse in daily use at virtually every major facility on the planet. It would not be a stretch to say that the U 67 defined the sound of the '60s. Now the legend is back — in a meticulous reissue, handcrafted in Germany to original specifications using archived documentation.