Yow! Nice purchase list!
It is easiest and most effective to change out tubes one position at a time. Traditional wisdom is to start with the V1 position. There is nothing wrong with that.
If your amp is a combo, sometimes it helps to have the back of the cab set up to be easily removeable and replaceable for ease of getting to the preamp sockets, also, it might help to place the amp upside down on top of a pair of rolled up bathtowels set one under each side so that the upside down amp does not rest on the carry handle and wobble precariously all over the place.
If your amp is a head, go ahead and take it out of the headshell, but make darn sure that nothing comes in contact with the amp's guts inside the chassis.
Some positions have different needs. For instance, if V5 is your phase inverter, it is best to choose a tube that has a very close if not exact balance between triodes for that PI position. The chance of all your recently purchased tubes being that tightly balanced is pretty remote. So if you take care of that one first, and it sounds good, then you have done yourself a favor. If you socketed your best balanced tubes earlier in the chain you might compromise the tone chain's overall potential by not having a balanced tube left over for the PI position.
Contrary to what many have written, my ears tell me that the PI position
does have an effect on the overall tone of the amp. So it is good to have choices between different makes of preamp tubes to roll for the PI...Shredd6 did up a great thread on Matsushita 12ax7 if my memory is correct dealing with that very topic as part of it.
One thing I have noticed is that at the limit of clean headroom (loud without any breakup) a balanced power section will sustain longer for a given note than an unbalanced power section. That means balance in at least three areas:
The sides of the phase inverter
circuit must be balanced... and you can't really do much but hope for that one unless you are a pretty skilled tech
The sides of the phase inverter
tube need to be balanced as previously mentioned,
The
power tube pairs must be balanced with respect to each tube within that pair.
With all that theory aside, DO take notes for each tube change for each position, and after you have finished with your "one position at a time method" lineup, just for giggles go ahead and try your dream lineup that you came up with in the origin of this thread, compare it to what you came up with doing the one at a time method... why not?
Best of luck to you, and let us know how things came out! Peace. 8)
