I know I've shared the story of how years ago we (and others) discovered the bypass cap—that small film capacitor placed in parallel with a big electrolytic.
If you look inside any PS Audio product you'll always see these small caps as neighbors to their larger relatives. They are simply what we, and I assume, any company in our industry does as responsible citizens wishing for the best sonics.
How this started, years ago, was on power supply capacitors. You know, the big caps that store energy and smooth out the 60Hz AC into clean DC? The ones the high-end deniers claim cannot matter because they are at such a low frequency and the bypass caps only work at magnitudes higher frequencies.
Yeah. Those.
Well, what's interesting is that not long after having discovered the benefits of capacitor bypassing in power supplies it dawned on us to try it in the signal path. In those days, everything was cap coupled: input and output capacitors on everything.
Boom! Bypassing those input and output caps was startling. Amazing. Add a 0.1mF film cap to a 10mF electrolytic on the input of a power amplifier and for less than ten cents, a major improvement happens.
And as in my post about forward motion, the next step was to eliminate the input and output blocking caps all together.
Direct coupled!
Step by step, we get better and better.
