I have observed (heard and then tested so as to confirm) the following “condition” as it relates to the widely debated issue of FLAC quality. The purpose of this topic is to gather opinions as to whether or not your observations are similar too – and therefore support – my own.

It is widely understood and accepted that a FLAC file while “compressed” is “lossless” as compared to its corresponding WAV file. Let’s assume (i.e. not debate) this is completely true. What I am noticing is that when the FLAC file is “played” via any FLAC player it sounds different from the sound of the “same” (equivalent decompressed FLAC) WAV file when played back via the same player that was used to play the FLAC file. This is specifically noticeable (to me) in the low frequency spectrum. The WAV has considerably more “sonic energy” that manifests itself as appearing to be a bit louder, wider in frequency range and perhaps even dynamic range as compared to the FLAC equivalent.

I’m curious as to your findings when you compare a FLAC file played natively as compared to the WAV equivalent played via the same player (for example, play both the FLAC and WAV via VLC media player) or practical equivalent, such as if the FLAC was burned to CD and you are comparing the FLAC played via VLC and the CD played via a CD player.

I am further assuming that the WAV file is a more accurate representation of the audio than the FLAC. This is to say that should you agree with the aforementioned, it would be preferable to play the WAV file or decompress the FLAC file before using it.

ddriveman made the perfect post. For discussion across everyone's systems his points reach the conclusions that will usually apply. Bottom line use AIFF or WAV, if if metadata headaches bug you, like they do me, use AIFF. Cheers,
One more vote to WAV files, altough I found sacd and high fidelty pure audio( blu ray) better in that order, so even most of my music are on cd, i prefer sacd.
I have been looking at flac compression levels some more .Let me clarify uncompressed flac, since I confused flac 0 and uncompressed above.

Flac 0 is not uncompressed. It is the lowest level of flac compression, but it is still far from uncompressed. Many packages create flac 0, but dBpoweramp is the only one I know of that does truly uncompressed flac. There may be others, but dBpoweramp is the one I know.

As an example, I have a track that is 69KB (39%) at flac 6. It is 73 KB (42%) at flac 0 and 122KB with uncompressed flac. AIFF and WAV are also 122KB. So, if you want flac with no compression you need uncompressed flac, not flac 0.

Flac and WAV both have well defined meta-data capabilities. WAV originally did not include meta-data, but many implementations do include meta-data today, although the implementations can vary. So, if using meta data, flac and AIFF are the preferred formats.

Conclusion - If you want an uncompressed format use uncompressed flac (not flac 0), or AIFF, with WAV an option if you understanding the tagging issues.

The higher the compression level, the more compute time  needed to do the compression. However, people who understand the flac compression algorithms say that the time to decompress the various levels (0 to 8) are basically the same. That may not seem intuitive but there are good explanations from the for the people who know. Uncompressed flac, however, should take not time to decompress, since it is not compressed.

Hope that helps clear up flac 0 and flac uncompressed. They are different.

As a relative newbie in digital world, I recently elected to rip my cd collection to have access to everything without going through hundreds of cd's. Using dB I started ripping at first in the flac default 5 compression. Playing back through my Magnum Dynalab MD 807T, I must admit that it sounded pretty good (at the time I did no A/B tests) After ripping many and coming to see that I did not need the extra compression due to using a external 4 drive enclosure for storing files, I deleted everything and re-ripped in flac uncompressed.

Having access to everything is a pleasure, but accessing through the computer seemed to be occasionally problematic. Errors popped up here and there (maybe once for every four hours of streaming). It presented itself as what I would describe as dropped bits, momentary silence etc. I then elected to move everything to a NAS and take the computer out of the loop for anything but operation control through JRiver. So I access the library through desktop/laptop or tablet and these momentary errors have evaporated.

Always one to read, experiment and verify, I am going to rip some cd's that are already in flac uncompressed format and sound exactly like the original material into WAV and playback using the same method above and see if there is any  difference that I can detect in my system. If not, I will consider myself lucky and continue using flac uncompressed and just get larger drives, if needed down the road.  

As a side note, I have been experimenting with changing playback parameters in the PS DirectStream, since it was recently added, to find optimum setting, there also there is going to be a learning curve but that's what a hobby is all about 
PS DirectStream is the one DAC that doesn’t handle input jitter at all, you will hear differences all the time with that DAC. Even $200 consumer receiver handles jitter better than the PS Audio DAC.

I’m so glad I was able to get rid of it at a big loss to me.

btw: jplay reduces jitter of PC audio output, you’ll hear a difference with that DAC. On the other hand with a properly designed DAC like the Emotiva DC-1 which has a built in reclocking circuitry, there will be no differences what so ever between formats/players.