So my main amp for a number of years has been my Laney LC15 but recently it's overall output volume has dropped to maybe 5% of what it could achieve before even with gain and volume nearly maxed out (I didn't used to be able to push it past about 3 on volume before getting complaints about the noise). I've been lead to believe this is a power valve problem, is that right? If so, how much does that kind of thing cost to fix? I picked the amp up for about £40 several years ago and am very satisfied with the tone and power, will it be worth it to fix it or get a new amp? I'm based in the UK so a GBP sum would be helpful, cheers
It seems as if your amp has 2 power tubes. A matched pair will be about $28 (so 17 GBP before shipping). Then you'll want to get a cheap multimeter and a bias probe to bias the amp once the new tubes are installed, which is a fairly easy thing to do yourself, you just have to be careful not to kill yourself with electricity. Multimeter+bias probe is about another 20 GBP before shipping.

I got my tubes for my Laney from Tube Depot, as well as my multimeter. Their bias probe is some assembly required so I got the one from Eurotubes (after I incorrectly assembled the Tube Depot one lol). I recommend the JJ E34L tubes.

All in all considering 40 pounds for that amp is kind of a steal and a new halfway decent amp would be at least 100 it would be worth it to retube and bias it yourself.
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The Stig1214 was 100% correct, go with his advice. When I had to get new valves installed in my Marshall the first time it cost me over £100. So being a Scotsman and not wanting to part with my cash I read up and bought the kit to do it my self, and I have done twice now. If you plan to stay with the guitar then look at it as a long term investment when you buy the kit. Always remember when you are working on the Amp " One hand in the back pocket, so if you get a shock it does down your leg and not through your heart to you other hand :-) " And you thought playing the guitar was exciting.

A pair of EL84's from www.hotroxuk.com is £20-25, not too expensive. Definately worth doing
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It sounds like the POWER TUBES, get a matched pair of EL84's (JJ EL84 seem to be the best new tube and fairly cheap.

I would suggest you get a new set of 12ax7's for the preamp also, but your issue seems power tube related
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