Thanks Riffraff for that explanation, very instructive. I'll see if I can get some of these tubes on ebay. The TAD 7025S that i put in V1 is, as they say, a recreation of the old Mullard tubes, long plate, and that makes a huge difference compared to the stock tube, I think a NOS will work much better. Tell you if i find something and will ask if worth it. Have a nice day folks. And keep on rockin'.