This is the schematic of my amp (135W MV twin reverb). In case i want to replace some caps in there, which ones would make a difference? Some people say that there's no clearly audible change if i replaced the ones in the tone stack. Not even the ceramics with silver micas? Could someone pinpoint the coupling caps, or any cap that could be replaced? I'd like to go with Mallory 150's because i really like them in my custom built pedals, although they are mostly suited for "Marshall type" amps.