Few of years ago, a friend once advised me (err sort like reminded me actually), that once you embark on DIY Audio, then be prepared for a never ending journey.
When I heard this, I thought "yeah, you're right", but here I am now, tweaking and tweaking, again and again, hahaha!
You see, last time I tweaked my Lucky13 Gainclone LM3886 amp with changing the feedback resistors, from metal to carbon (Allen Bradley/Morganite), tweaking the input resistors to use a combination of carbon and metal, upgrading the filter capacitor on the PCB Board to Low ESR caps (Panasonic NHGs), then bought Russian Caps K42Y, K40Y, and K75Y from eBay.. applied them as bypass for electrolytic caps and some used as signal/coupling caps
Latest tweak? Well, I ordered 1uF/630V Obbligato Supreme Caps then I installed them as signal/coupling cap. It truly improves the performance of my Lucky13... though not Night and Day but overall improved.
Was that the latest journey?
Apparently not! Hahaha...
Last weekend, I tweaked the PSU of my AikiDino Pre-amp (again), by adding a pair of Rifa PHE Silver Caps 1uF/250V connected in series, parallel to the 2x 2.2uF/400V Bennic Cap, plus 0.47/250V K75Y Russian cap (also connected in series)...
Confirmed mi amigo, you are 100% correct!!
It is a never ending journey, similar like the Life God has given to us!!