Got a vintage 1969 valve amp. I've changed the tubes a few times but I've heard that u should change the power caps too....is this true and if so....how the hell does one get hold of these rare caps.
Yes, indeed! Electrolytic caps only tend to last 10-15 years, their dielectrics break down over time and tends to lead to a loss of bass, hum and eventually cap failure. I'd not only change the power caps but ALL the polarized caps as the same time and be done with it.
I'm also of the opinion you should rather pay ONCE for QUALITY caps that will last another 10-20 years, like Sprague Atoms. I've JUST ordered in a set from the USA for my 67' Bandmaster, and set me back around $50+ USD for all the lytics.