166.137.88.47
This Post Has Been Edited by the Author
In Reply to: RE: EL 34 for Marantz 8B posted by jazz251 on June 20, 2012 at 11:50:34
...the 8B was designed specifically around the EL34. Note that the EL34 is one of the few audio power pentodes where g3 is brought out to a separate pin instead of the usual practice of internally strapping it to the cathode (6L6 etc). If one looks at the schematic of the 8B, one finds that g3 is not tied directly to the cathode as it is in almost all other EL34 type amps but rather, goes thru am RC network instead. Therefore, by stuffing 6L6 types in there, one defeats this design subtlety that is unique to the 8B AFAIK. Due to how the sockets are wired, 6L6 types will work ok but the output circuit is not as designed.
Persons who should know better indisdciminately make tube substitution recommendations w/o proper familiarity with the details of the amp under consideration. Bottom line: an 8B is not an ST70 and should be treated accordingly...IMO of course.
Follow Ups:
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2012, Audio Asylum, all rights reserved ]
[ Take5 ]