Well as you may or may not know, the Blues deville although a great sounding amp has somewhat harsh high ends when it gets louder. now I've heard people say they have replaced the 12ax7 in the V1 postion for a 12AT7 and it calmed the high's and made the amp more controllable. has anyone ever done this? and how did it turn out sounding?
After having this problem I can identify with this “head room” problem. I went online and found a “Blues Deville” (reissue) replacement tube set. Torres Engineering offered a replacement set and it worked to perfection. The following is what was included:

From the back, Left to right:

Two matching 6L6 Tung-sol 5881
1 Groove tube (SAG- AX7-mpi
1 Sovtek (5751)
1 Tung-Sol 12AX7

Amazing like new now, I recommend this set-up