Miku39 sorry for taking so long to respond. to answer your question Error correction doesn't add jitter it just cannot fix all of it Jitter is a timing based distortion so any time domain changes in clock speed and timing effect the sound in phase coherence, sound stage, and frequency recomposition. basically the less fixing you have to do post facto the better the result, because the error correction can't reconstitute data or timing information that isn't there, or if it is there the error correction can only do so much to fix a jitter damaged signal. I can tell you that I have heard 4000 dollar clocks put on really good CD players and heard it make a huge difference it was as if I stepped forward a few rows in a live instrumental concert I heard better attack and decay artifacts and the like. The transport and clock and the effects of jitter can effect timbre, as well as pace rythm , and timing. Compared to analog digital doesn't usually convey decay all that well, There are exceptions with better clocks and jitter control and the like, but this is why the small differences can make a huge difference in the realism of a signal.
in an SSD vs HD comparison I would imagine that HDD with it's read mechanism would potentially impart more jitter than SSD Cashing probably avoids much of this, but I am not sure what it is cashing it could be cashing with already jitter laiden signals and therefore SSD would eliminate much of this intrinsic jitter. Much of this technology needs to be tested and better testing for jitter made right now we can only theoretically test beyond 10 pico seconds of jitter there are no scopes that can test beyond this at this point even though less jitter artifacts are still audible and effect every part of the signal. Reconstitution of a digital signal after it is damaged is like trying to added image stabilisation to a shaky video, you can "correct" for this in post but your images will still look magnitudes better without any shaking" the same applies to jitter.
