Tube rolling 12AX7As

It takes 6 tubes, 2 each for the preamp stage, the mm phono stage and the mc phono stage. It will take 12ax7's. New old stock Telefunken 12ax7's seem to be popular however when I had mine I enjoyed new old stock Mullards. You do not have to replace all 6 tubes, your phono needs will dictate whether you need to place any good tubes in your phono stages.

Have fun but take your time when removing the cover and the subsequent removal of the tubes. There is a silly and poorly thought out tube "holder" that will require you to remove screws on the left and right of the the tube section so the top tube guide can be removed. Use both hands so you dont drop the screws into the preamp. Dont ask me how I know this can happen.

Brad,

a good plan you have there and I admire your patience. Make sure and place the type of tubes in the preamp section that you want to use to flavor your system and you may wish to consider neutral tubes for your phono stage.

Now, I may be setting myself up for a flame or two but there will be some who believe breakin wont completely occur unless your preamp is connected to an amp. They are wrong and likely still live in their parents basement. As a matter of fact, they probably just dropped their video game controller while reading this heresy! LOL.

Brad, I would not worry too much about performing any tube upgrades until you get your amplification sorted and acquired. If I'm not mistaken, the headphone amp of the C2300 is an op amp so the funds spent on NOS 12AX7's might be better utilized presently toward your fund to purchase an amp. In other words, the addition of either amp would be top priority over flavoring the output of your preamp, which you likely would not be able to discern through the headphone outs of a C2300. My 2 cents would be to save for a 275, the 240 being kind of an enigma....not as sweet and lovely presentation wise as MC30's and not as crisp and articulate as the 275 editions. Good luck with your journey.