Tube change question

[pivot]

I had a hard time finding the answers to these ?'s so please forgive me if they have already been answered.
1. Im getting close to the 2 year mark. I play 3 to 4 times a week for 2 hours a day. when should I replace the pre-amp tubes and should I replace all pre-amp tubes or just wait for them to go out?
I saw allot of posts saying not to replace all the pre-amp tubes that they are put in a specific order for a reason. How do I know when to replace and what order? I would rather not have then blow out on a show so im over cautious. I bought a SPAX7-A as a backup should I replace them all with these? I want to keep the tones I have now in the amp so I dont want to do something wrong when replacing the pre-amp tubes.

2. I use channel 3 in 90w pentode mark 4 mode. Reading the manual it sounds like the rectifier tube is not being used when in the mode and wattage. How often should I replace the rectifier tube.
I replaced the power tubes a year ago. I plan on replacing them yearly.

 

[gman1951]

Generally speaking, there is not a lot of wear and tear on the preamp tubes, so the should last a good long time. If you satisfied with the tone you presently have, I would suggest just leaving these alone because changing these tubes could DEFINITELY change the character of your amp. If you do change them, and are interested only in modern tubes, I would stick with one of the reputable dealers such as The Tube Store, Eurotubes (among others). They sell tubes closely spec'd to the tubes that come stock in your amp, so you should not hear much difference in what you hear now. If you do use Eurotubes, Bob will probably ask you whether or not you want the high gain set, which I recommend because, at one point, I requested the lower gain set and ended up putting the old tubes back in.

If do you decide to use NOS/ANOS, do your research before you buy. Online stores include TC Tubes, The Tube Depot among others (google NOS tubes for a greater assortment). You could also take your chances with ebay. Just make sure the spec's are listed and are specific.

Oh, and always keep a spare of each tube type handy.

Hope this helps

 

[pivot]

thanks! that is what I was thinking. When I do replace the tubes I plan on buying them straight from Mesa boogie. I still am confused about the statement they made that the pre-amp tubes are put in a specific order and can change the sound if replaced. Does this mean if I put in the Mesa preamp tubes purchased from mesa in place of the existing preamp tubes that my tone will change?

Do you know if the rectifier tube is being used if I am in 90W mode?

 

[jmontgomery]

I think what they mean by a specific order is the V1 and the V2 tubes are where your guitar signal first gets amplified so you need a good quiet tube in those spots. If you stick a noisy or microphonic tube in the first gain stages it's going to affect your tone. If your happy with your tone leave the preamp tubes alone. When you do change them put your best tubes in the V1 & V2 spots. Without looking at my amp I'm pretty sure your rectifier tube isn't being used in 90w mode.

 

[pivot]

Great thanks!!