About 2 hours ago, I got delivery of another 1678 Melz tube from Russia after one week from placing order.
Very fast shipping.
I had not got tubes from Ukraine that I ordered 5 weeks ago.
It was made in 1980 and looks clean as Nos tube.
After playing demagnetization track, I am listening to familiar music to me.
"Thriller" by MJ sounds spooky with deep and full bass, wide and deep soundstage.
Its bass, decay and soundstage is just beyond any other 6sn7 tubes.
But people may get the impression that it is bass heavy.
Now I have three pairs of 1587 Melz tubes and eight 6n8s tubes, I am going to stop shopping of 6sn7 tubes.
After being back from Kr vt231 this morning, I found that 1578 has more body and decay while KR give almost same amount of details as 1578.