6EA7 - 6EM7 - 6DN7 - 6GL7

6EA7 - 6EM7 - 6DN7 - 6GL7

Once an obscure TV tube, the 6EA7/6EM7 has really made a come-back due to it's usability in high end audio. 

Direct equivalents & compatible tubes: 6EA7, 6EM7, 6GL7, 6DN7.