6DJ8

The 6DJ8 is a miniature 9-pin medium gain dual triode vacuum tube. It is distinguished by its very high transconductance, mostly the result of its frame grid construction.

Origins

Developed by Amperex in 1958, the 6DJ8 was originally designed for use as a low-noise amplifier in VHF and UHF TV tuners, an improved successor to the usual 6BK7. But its high gain won it many designs in high-end test equipment. Most high-quality oscilloscopes from the 1950s thru the 1960s have many 6DJ8's tubes, often a majority.

Audio

Although not originally designed for the purpose, it became popular in hi-fi audio amplifiers. European-produced version of the tube is designated ECC88. An industrial (improved/higher ratings) version of the tube is designated 6922. New Old Stock (NOS) 6DJ8s and ECC88s produced in the past by major American or West European vacuum tube manufacturers (such as Philips or Amperex) remain extremely popular with and highly sought by audiophiles. A version (direct equivalent) of this tube was also produced in the Soviet Union under the designator 6N23P (Russian: 6Н23П) and in China, under the 6N11 designator.

The tube is currently being produced in four versions in Eastern Europe - Slovakia by JJ Electronics (ex-Tesla), Serbia (Ei) and in Russia - 6DJ8 for Sovtek and 6922 for Electro-Harmonix.

See also

*6N1P
*6N3P

References:

[http://tdsl.duncanamps.com/show.php?des=6DJ8] - 6DJ8 tube data at DuncanAmps.