Have found to make an improvement:
1. Ethernet cable directionality
2. ST Optical cable directionality, optical gel, aftermarket optical cables from Aural Symphonics
4. The right receptacle on a UK type AC duplex sounds better
5. Directionality of grounding cable (for turntable-to-phono purpose)
6. Directionality of grounding cable (for internal or external grounding CD player, pre-amp, power-amp)
7. Tap water as the final rinse on CDs, SACDs, and Vinyl Records
8. Contact-less Cleaning and Drying for CDs, SACDs, and Vinyl Records
9. Unplugging the Fridge in the house (or at least make sure the fridge door was never open/close during listening sessions)
10. Powering off Optical Disc Players before playing any CDs to clear residue playback memories
11. Certain types of belt drive turntables need to be powered off and on before playing another vinyl side
Have found to make sound worse:
1. Shakti Stones (but I continue to use them to treat CDs and SACDs)
2. Cable risers
3. Cat's fur brushing against audio cables' dielectric jackets
4. Human hand/skin touching audio cables' dielectric jackets while the whole system is powered up
5. Audio Racks made of Metallic Materials
6. Turntables' plinths, platters, and clamps made of Metallic Materials
7. Using a record brush on a vinyl record
8. Using a record brush over the vinyl record while it is spinning prior to playing the record
9. Stress and tension on audio cables and powercords
10. MOFI SACDs and Vinyl Records
11. Flac files
BTW, i love cats
I posted about this additional tweak that can make a difference something like 2 weeks ago.
[[ When the cd player has been totally powered down, pressing the buttons on the front panel a few times. ]]
I found that it helps not only on my CD player, but it helps quite tremendously on my Bergmann Modi Turntable as well.
On the Modi, other than the ensuring that the directionality of the umbilical cord is correct, I also practice full powering down of the pump/motor before playing every sides, and now I've just discovered another new trick to improve the sound even further.
It's similar to what I've also just discovered on my Playback Designs MPS-8 Player, and that is - when the Modi pump/motor has been fully shut down, if I press the 2 buttons on the Modi plinth a few times, before powering up again and playing, the resultant sound will be even more clearer, more detailed, and more opened.
The inspiration for this tweak came from a china co-worker in my office.
Usually on the test systems that I'm working on, right after a firmware upgrade, I would usually shut down the system and unplug the powercords to allow the system to fully dissipate any residual "something" (for lack of a better technical word). Just recently I noticed this china co-worker pressing the buttons on the system a couple of times instead of unplugging the powercords. According to her (she's a software engineer) this works just as well to clean up the system and allow the new firmware to properly settle.
I tried this on the MPS-8. On top of my usual powering down of the player totally, I pressed all the buttons on the top panel a few times. When I next power up and play a cd, oh my God, the sound improved so much!
So i tried it on the Modi.
The detail resolution, openess, and sense of musicality went up another level.
LOL I love discovering new ways to improve sound without spending any money.