Something not said explicitly but to me, is the characteristic sound of psy-x is the synth bass line. It's a very simple sound that you can make in any subtractive synth - you start with a single saw, add a lowpass filter, and instead of using the amplitude envelope to control the dynamics or "pluck" of the sound you modulate the cutoff of the filter by an envelope with a very short attack, quick decay, and low or ze…
regarding the pumping, I'm not sure if sidechain compression is what most producers are doing. I'd describe it as a gallop rather than a bump. so with 16ths, you'd typically see 1/16 & 2/16 have zero to little amplitude, 3/16 & 4/16 have most of the energy. 4 maybe even a little less so. which can't be done by sidechaining. also phase alignment with the kick is important
Yes phase alignment is important too. There's always a sweet spot where it just sounds "right". Plus staring endlessly at an oscilloscope to check they aren't interfering. Then doing it for hours and hours and wondering at the end if it sounded better before you started mucking around with it actually but your ears are so tired of it you can't tell anymore.
This stuff is such a rabbit hole. Lots of fun though.