by paart » Wed Jun 12, 2013 1:47 pm
Over the years, I've read that there were two variations of the Z565: 1/ The original US made units with cloth leads, and 2/ Japanese made transformers identifiable by vinyl covered leads. I have examples of each of these, and a third with both cloth leads and vinyl covered leads! Unless anyone has additional information, I'm going to guess that the US manufacturer was slowly changing over to vinyl insulation, before the source was changed to the Japanese firm.
I have never noticed any sound quality difference between the types, nor have I ever seen others comment on it.
Years ago, John Atwood presented an extensive evaluation of OTs used in major manufacturer's tube amps. The Z565 was given the paper's "A" or highest rating. The other Dynaco offerings were generally rated somewhat lower.