I am looking at purchasing a Marshall DSL401. It is 40 watts and has a 12" Celestion. However being that this is my first tube amp, as well as first Marshall, I have a few questions.

1) How much is it to retube it assuming it has 4 EL84s and 4 ECC83s?
2) How often must it be retubed?
3) Is 40 watts of power out of a 12" enough for a small gig and jamming with a drummer? My friend's 60 watt DSL stack only has to be turned up to about 2 or 3 to be plenty heard over a drummer and various other amps, so I'm guessing that unless the speakers have a huge bearing on sound that this will be enough. By 'small gigs' I mean playing to an auditorium of 200 people at the school Battle of the Bands or playing to about 75 people under a tent at a small festival. Anything louder hopefully I can just mic the amp for anyway.

Before anybody says "LOLOL BAI A FENDAR HOT ROD DELUX LOL" be aware that unless there is any pressing issue with this particular amp I'm buying it come hell or high water. I have used the head and I love it - I don't particularly care about the 'deep switch' or other such tripe, since I have a Guv'Nor and I could use that if I really wanted to to get a 'deep' sound.
Steinberger GU/Spirit w/ Moses Graphite neck, EMG 81-85
"Fireball" Pacer/RG hybrid

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Peak FCB4N
1) $71 from EuroTubes
2) Depends how much you play it, and at what volumes. The old ones in my 5150 were in there for 3 years, but they can last as little as 1 year. Pre-amp tubes generally last a few years longer than power-amp tubes.
3) Yes, 40 watts tube is equal to about 100-120 watts SS. It's LOUD, trust me.
Quote by Dave_Mc
I've had tube amps for a while now, but never actually had any go down on me
Quote by jj1565
maybe you're not saying the right things? an amp likes to know you care.