Why do Wav and Flac Files Sound Different?


This article is from 2016, so outfits like JRiver may have developed workarounds for the metadata/sound quality issues sussed out below. Inquiring minds want to know.

Why Do WAV And FLAC Files Sound Different?

"Based on these results, we attempted to pinpoint which section of the metadata might be responsible. Since the cover art file associated with the metadata is the largest contributor to the metadata header size, we began by examining the effect of deleting cover art prior to the WAV-to-FLAC-to-WAV conversion protocol. This proved fortuitous, as our first suspicion proved correct."

bolong

@aldnorab I do not know and it is not important regarding quality of the audio file.

A "song" can be transcoded as many time as you want and no "musical" information is gonna be missed (remember we are in digital world and information means 1s and 0s)

This is assuming that you transcode among lossless formats: ALAC, FLAC, AIFF, WAV and any other: so streaming company can receive a WAV file from the majors and transcode it to FLAC as it is the most "commercial" one

The only thing that could be lost is metadata (like image, composer, group, orchestra, year, ....)

Regarding your question, I guess that they supply FLAC because is universal: can be played in almost any system and has a very good capacity for metadata. Anyway the streaming company can receive a WAV file from the majors and transcode it to FLAC as it is the most "commercial" one. But honestly, I do not know.

@bolong I do not know for every case. What I have seen when I have bought music from Qobuz is that they provide an image that you can see in the FOLDER where the music is and when I have retagged every SONG FILE in order to add information important for me, sometimes there was the same image in each song file. The same applies in the case of music that I have bought from other online shops (Presto, Highresaudio, etc.)

For each song the cover art and all metadata is "separated" from "music" in each MUSIC FILE: for understanding this, it helped me very much to realize that all the information (music, song name, duration, composer, singer, orchestra, group, ...) is a very long row of 1s and 0s but similar to a very long train, the 1s and 0s for music are in one big wagon, and metadata goes in one or two or three small wagons. Following this idea, WAV only admits one metadata wagon whilst FLAC, ALAC, AIFF admit all the wagons. Metadata wagons can be full, empty or something in between

Please, this is not "scientific" at all, but this idea helped me very much. I hope it can be useful for you and not confusing.

The only way you’ll ever convince me there’s a lick of difference between WAV and FLAC is with the jitter measurements.

It is _possible_ that the decompression has so much of an effect it overworks limited or pooor buffers and jitter control mechanisms, but IMHO, it’s the 21st century and any streamer at all in this day and age should perform equally well with either.

I should point out that any of this should be VERY streamer dependent.  Unique CPU's, algorithms and real-time software is probably running on each of them, so the idea that this is something shared among all of them is not believable. 

Also, take Roon, which essentially reads the files in the server and then seends them to each endpoint separately.  The data stream sent by Roon has been stripped of it's original format. What happens then?

The gist of this thread had to to with the possibility that any metadata was a potential pollutant of the musical information. When I used to download albums from allflac.com removing the "cover" file from the track list before loading it into JRiver would nix the cover art showing up in the thumbnail header for the albums which seems to indicate that this data was no longer involved in the track files. Not the case with Quobuz. None of this may matter sonically. Or it might in some small. way.

OP:

The metadata and audio are separate. They share a file, but it’s not as if the album cover art is being sent per musical frame. It is in a different location, along with all the credits, so once the music starts to play, it is completely out of the picture. At best, these should could cause picoseconds of delay in starting to play the music, but zero when playing has begun.

HDCD and MQA however are interwoven into the music data itself.

It does take a little more CPU power to decompress FLAC or ALAC vs. WAV, which is going to take more network time, but if your player sounds different, it's messed up.