Yeah, not to take things seriously, but really? Come on guys, someone should help here so I'll jump in. I'm not trying to be a prat but some of these ideas are pretty........... well...... out there. Just look at the facts and realize what each of these things actually do.
- The X3's internal battery is the
only thing that runs the player. Adding other power sources only charges the internal battery (none of the
external power goes toward the sound quality) and when that's done the power is no longer drawn from the external source. So no, a power supply does not alter the sound. Plus leaving a battery constantly plugged in significantly reduces the life of the battery. Battery chemistry is meant to be cycled.
- The USB on the X3 is there to provide data (0's and 1's) while transferring files or while playing files as a DAC from another source, and it charges the battery. That's it. No change in sound from USB cables (unless you get interference through the cable from an external source).
- Upsampling will have no positive contribution to the sound (in many cases it will be detrimental). You can't add something that isn't there already even if it could be heard. So no, upsampling does not benefit the sound.
- Although many people enjoy WAV as a lossless format it really doesn't bring anything more than a FLAC or ALAC file will on the X3 (and I'm pretty sure WAV64 is not supported, plus FAT32 doesn't support files larger than 4GB so no benefit there). If you already have files in WAV format there is nothing wrong with that but they are all lossless and reproduce the same sound
if the player can decode them properly, which the X3 can. So WAV doesn't affect the sound in this case and just gobbles up more space on the storage media. Larger file sizes also may run the risk of causing stuttering and skipping during playback.
Some people enjoy their placebo effect, but man, this is just..........
Should be an episode of Mythbusters.