1) OK, you are a scientist.
2)Yes, Cd is very vulnerable to vibes like turntable.
I use carbon/kevlar plates with ceramic cones and steel/teflon "Fadel Amethyst cancellers".
"Relaxa" plate is even better (the device is in "levitation" due to two plates repulsing each others with powerful natural magnets.)
Free tip: check with a plumb level that your CD/turntable
is perfectly horizontal. If not, it creates vibrations which affects dramatically the sound.
Use hard matters like dense wood pieces to equilibrate your device in order it's perfectly horizontal.
If you don't hear nothing, it's because your system is not transparent enough.
Valves are vulnerable to vibes.
any composants are vulnerable to vibes.
Even transistor amps are vulnerable to vibes
Eventually all devices!
3) Yes, a battery is the perfect power source, cause it delivers stable power.
But more than power variations, pollution between devices is what affects worst the sound.
4)I swear that good cables affect dramatically the sound.
Good interconnect cables is the fisrt step to reach a
good level of transparency.
Without it, you can't hear nothing.
For low budget, i advice Qed Cables, musical and neutral english cables.
For higher budgets, i suggest american brands such as Kimber, Synergetic research, and of course Transparent cables which are the best of the best!