Removing chasis to changing V1 preamp tube.Advice needed

[diddlydan]

Bought a used Mark V a few months back and the original owner said there was a different tube in V1 position.Curiosity has got the better of me and ive picked up a mesa spax 12ax7 to replace it with.From what ive read its damn near impossible to get near the V1 tube unless the chasis is removed.I have no idea how to do this bar obviously turning screws ha.Ive also never changed a tube before so im worried ill do something stupid.Are there any things to look out for when removing the chasis and changing tubes.Im considering bringing it to a tech but doing it myself will not only save me somes cash but ill also learn how to do it.Cheers

 

[borisson]

i ve changed the V1 in my Mark V head without removing chasis...its not easy but you can get there through the back of the amp...

 

[jmontgomery]

You can take the cover off, pull the tube and replace it fairly easy. It's a fingertip job and you'll be doing it by feel. Putting the cover back on is the hard part. I broke the tube the first time.