RCduck7:
Intresting...
http://www.skipsimmonsamps.com/truthaboutvintageamps.html
have read that a few months ago (was discussed in detail on another forum) ... I don't understand all the techinical jargon, but this is how I understand the issue
problem is that when the capacitors start to 'bulge', it's time to recap ... capacitors can last up to 30yrs if the amp is not used often, and some say capacitors have a lifespan of approx 1000 hrs of use
as regards altering the sound of the amp, it will change if more modern caps are used and not the original ...
I opted for expensive ones which are regarded highly, and can say it has changed for the better and is really sounding good ... but before deciding which caps to use, visit a vintage forum and seek advice/opinions
other issues are dry solder joints, deoxit on all pots, recalibrating etc etc .... plus replacing all internal cabling with decent silver cabling .... there is even an issue with the solder wire .... (something to do with the silver content)
was money well worth spending ....
IMHO if you have a good quality vintage amp, it may be worth your while to spend a little have a good job done