sonic frontier line 3 tube options

I have a Line 3 and replaced the back two tubes with early 60's Siemens CCa's - a very noticable improvement in sound quality.
Then I got to thinking what the other positions would sound like with NOS tubes instead of the stock Sovtek's (have read posts that it does not make any difference). I replaced the remaining eight with mid 1960's Phillips 7308's, I was once again WOWED with the improvement in sound quality.
So it seems to me that the better the tube in any position...the better the sound quality.
My two cents worth

You only need to replace the pair of 6922 that is closest to the rear end.
These positions generates 100% change in sound.
My Line 3 has been upgraded to SE.
In my system I have found these tubes to generate the best sounding music from my Line 3:
Amperex 6922 PW 1960 production
Siemens CCa 1958 production
Valo E88CC production 7LH 482 Kevin Deal
Ediswan 2492 KB/AD and CV5358 Kevin Deal
Amprex 6922 white label

Hope this helps. Terry

I would really suggest that you contact Kevin Deal at Upscale Audio (www.upscaleaudio.com). I have taken his advice on probably a dozen different tube units (DAC, Preamp,Amp etc) and he has NEVER EVER failed me! He knows more about retubing equipment than anyone that I have ever encountered. I think that his prices are more than fair considering his knowledge and experience!!!