Here is a dumb question. I assume that replacing caps requires soldering...which I do....but very poorly. But do tubes need soldering or wiring? My old memories of tubes is that they simply plug in which would mean that tube replacement would only require removing the top cover, unplugging original tubes and plugging new ones in. So is tube replacement a DIY job?
I'm mainly asking is that with an old unit like this I assume they will fail at some point.
How do you know when they fail? Do you lose all function, just one channel??
Final dumb question, if one fails do you replace all 4?
Thanks,
George