almarg speak English, my head started hurting, followed by flashbacks of science class.....lol.
The point I was making in my previous post was simply that while the impedance situation in the connection between the preamp and the power amp is not ideal, and does not conform to the recommendation stated in the manual for the preamp, I’m pretty certain that it is not what is causing the symptoms you have described. And I expressed agreement with Ralph (Atmasphere) that a tube is the most probable culprit.
The reason I went into further detail in that post is that you had referred in your initial post to "the impedance thing that Im just learning."
almarg, don’t know a thing about the imped factor. and do you still have that 17ls. or what preamp goes best with the dna 500....
It was another poster who referred to the 17ls, not me.