Yes, anything outside checking the tubes and you'll need to take it to a pro. I'm definitely a DIY'er myself, but people can die if they don't know what their doing with tube amps...it's where I personally draw the line. I would recommend finding a good tech (ask guys on here in your area for one) and let the tech figure it out. You'll pay more, but save yourself in hassle and possible life shortening (or ending lol)
