Can bit identical files sounds different

Often there are reports on audio forums about differences in sound quality caused by using different ripping programs like dBpoweramp or EAC, different optical drives e.g. Plextor versus another brand.
The question most of the time is “have you done a binary comparison”?
The answer is hopefully yes but they still do hear a difference.


Can bit identical files sound different?

An obvious first is that you have to compare the audio part.
People often do report a difference because the file size differs a little.
This can be because one piece of software adds a block of free space for the tags and the other don’t.
Hence if you compare, compare the audio part only e.g. by using the Foobar binary comparator.


If both files are bit identical, can there still be an audible difference?

This is highly unlikely because you send exactly the same samples to a DAC.
But what about the jitter?
Jitter is not part of the audio file, jitter is a property of the playback chain.
It is a inaccuracy in the timing. As a file is something stationary residing on a storage medium it doesn’t have jitter just like vinyl of a shelf doesn’t have wow or flutter.


Is it totally impossible that bit identical files do sound different?

As a matter of fact bit identical files are not identical files. You can’t have identical files on a storage medium as the space on the storage medium can be occupied by one and one file only. The other file will be on a different location.
To assume that this will make a difference e.g. a file that is contiguous and one that is scattered of the storage medium generates different noise patterns when read cannot be completely ruled out but it assumes a system horribly sensitive of noise.
But even if this would be the case, the result will be random not systematic like a rip made with a Plextor optical drive always sound better.

Is it possible to hear difference between bit identical files even is the is impossible on theoretical grounds?

Yes, that is how the human being works.
Our ears transmit the sound to our brain
We also have out cognitions e.g. Plextor is the best optical drive there is.
Our build in mixer mixes the sound and our cognitions without us being aware of it to something psychology calls perception.
Hence it is very easy to hear the differences but they are not necessarily real.


Yes, all three horizontal lines are of equal length but our perception tells us something completely different.



The dBpoweramp / Exact Audio Copy Sound Experiment - Do you hear the difference?