There is always debate of whether firmware update affects sound quality for just about every DAP / software / gears. Below is a link to download a zip file can contain five 30 seconds music clips that were played by FiiO X5 on different firmware version, then recorded in identical setting (Focusrite Scarlett 2i2 + Audacity into PCM wave, then converted to FLAC). See if you can tell any difference. If you can, tell us which one is better / worst. It shouldn't matter if you use X5 for playback or not, but do try to use your most revealing gears.
Firmware version will be revealed in a week.
Just for extra fun of comparison, please add the music clip below to the above comparison:
Here are 6 more music clips, about 1 minute each, for another round of comparison. They are produced using near identical condition as the previous 6 files. The difference is that these are live recording / orchestra work so hopefully they will offer higher dynamic range.
For those who have yet to try, just listen to the music clips first before reading the answer.
Now it is time to reveal the answer:Warning: Spoiler! (Click to show)
Music clips - Firmware version
A - v2.2 final
B - v2.02 beta
C - v2 final
D - v2.04 beta
E - v2.2 final
F - original FLAC
G - v2.2 final
H - v2.02 beta
I - v2 final
J - v2.04 beta
K - v2.2 final
L - original FLAC
Basically, A and E or G and K are recorded under the latest firmware, to act as an control. F and L are the original copies, simply chopped to the right length as the recorded sample. If you find either to be better sounding than the rest, then you are correct. The big question however is, does any of the firmware version sounds different from the others? For that, we need a help from a software call Audio DiffMaker. I won't be bother with you for all the detail about this software as there is a published paper you can read on its page. In simple term, this software takes two pieces of recording, find out the difference and make it into an audio "subtraction" clip. The process is not totally perfect, but if the resulting clips is very low in volume, it means the two original clips are extremely similar and can be concluded to have no audible difference to the human ears.
The result is, all recording via different firmware should make no audible difference, as the differences generated using different clips on average go from -55dB to as low as -72dB (counting into the error generated by Audio DiffMaker itself), which are all below what human can detect between different tracks. In contrast, the differences generated using the original FLAC and the recording are within -20dB range for the first 6 clips and within single digit dB for the last 6 clips, and well within detectable range. The reason F is less differentiable to A~E while L is more differentiable to G~K is because the music used in L has better dynamic range as a music and therefore any difference between original file and the recordings are more apparent.
Below are two samples of the subtracted clips
^ this is A vs. B. Comparison between A~E are all pretty similar.
^ this is A vs. F
Edited by ClieOS - 8/24/14 at 10:02am