I recently aquired a Mesa Boogie Single Rectifier 50. I think it is about 6 years old. It hadnt been used in 3 years or so i believe. Anyway its still running on the stock 6l6s from the factory. Should i be looking at changing these out? THe amp works anyway, although Im feeling there's a lack of gain on the dirty channel, in the modern mode with the gain half way it should be screaming but the distortion isnt all the way there. As far as im concerned,.maybe i dont have it loud enough to get the full effect but i dont know but there is definitely distortion there.

New tubes?

In terms of installing them, is it a case of taking off the back panel, pulling the old ones out and putting the new ones in? is there any soldering required? should i take it to an amp tech to sort out a tube change?

I dont have any experience with this so any help is appreaciated
You don't need to any soldering or other crazy shit if you are just swapping tubes, unless you would be changing tube type altogether, and that would require re-biasing and in some cases socket modding.

The issue is most likely not being caused by the 6l6's, though it would still be worth replacing them sometime soon if you get the chance. They'll sound better for sure.

If the main issue is with the gain, the problem most likely exists with one of the preamp tubes. First be sure they are seated properly, and if they are but you are still having issues, look into replacing them.
i think new tubes would be a good idea. as far as installing them goes you would be best off bringing them to a professional because most mesa's need to be biased otherwise you end up using your tubes to fast or you wont get enough of a punch from them just be prepared to spend some money. no soldering at all but not sure how to open the head up.
If you buy Mesa branded tubes from mesa,you can just swap the power tube out without biasing the amp. The pre amp tubes give your amp its gain, so I'd guess it is a per-amp tube that has gone bad.
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