Hey, Its been a long time since I have been on here, dont know if anyone remembers me but anyways I need to buy Tubes online because Im thinking that the tubes in my Marshall Jcm2000 are getting old because I bought it used and have had it over a year without any tube replacements, I have $100 and I need something new before Saturday so I need to buy quick, Should I buy new Pre-amp Tubes or the bigger tubes??? For better tone. I dont know which ones might give out first, and I know I need to get them replaced by a real technician at a music store and I dont know how long it takes to Bias an amp head. Could you please help me with knowing what to get and if any recommendations on what brand I should get, thankyou.