Hi. Computer scientist and algorithms expert (and audiophile) here to chime in. Interesting discussion so far, but I thought I'd respond to a few points. To preface this, let me say I am all for improving audio and the way we listen to it, and I find differences in DACs and transports and digital processing solutions to be a very worthwhile pursuit and I'm endlessly fascinated by those kinds of optimizations. However, FLAC vs. WAV is not one of them.
Just means the FLAC codec isn't as mature as the WAV then. They all have the end-goal of producing a bit-perfect PCM stream.
They don't just have the end-goal of producing a bit-perfect PCM stream, they both do
produce a bit-perfect PCM stream. There is no problem with the FLAC lossless codec or its implementation. I know, I've tested it, and I've verified the algorithm and the underlying code. The digital stream coming from a FLAC file isn't just supposed to
be identical to the WAV, it is
identical, and provably so.
WAV exceeds the audio quality of uncompressed FLAC by a margin of 10% or so.
This is scientifically impossible. Were there a failure in the FLAC decoder or in the FLAC codec, the bitstream going into the DAC would differ. It does not, ever, 0% of the time, once again, provably beyond a shadow of a doubt.
... several engineers who would know say that the articles are full hooey.
This is 100% correct. The articles are describing a difference which is physically impossible and can only be the result of false perception or conflicting variables in the testing process.
While a casual listener wouldn't care about the difference, critical listeners definitely will. The most obvious thing was the soundstage collapsing to 1/2 size on the FLAC files.
This, too, is physically impossible. The digital stream output by your DAP is going to be 100% exactly the same from a FLAC or a WAV file, regardless of the decoding process or the format. They are the same bits, and bits are either on or off—there is no in-between. It's not possible. The only limiting factor in the digital processing is the transport and the DAC, which both come after the PCM stream is generated, and the PCM stream generated by the WAV and FLAC files from an identical source are mathematically provable to be identical. In short: if you hear a difference, you are making it up.
I realize this may be difficult to understand when we're used to describing such small and subtle differences, many of which I fully support, but this is one case where having a little knowledge of algorithms, mathematics, and provability comes in handy. This basically means that in the realm of computers and digital processing, there are certain things you can't argue against, things which are mathematical facts. And the provability of identical bitstreams is something we understand so very well that we can say that this is a mathematical fact, no ifs ands or buts about it.
Please let me know if anyone has any questions about this, I'd be happy to help you understand further. In the meantime, please feel free to encode all of your WAVs or CDs in FLAC format, and as long as you have players which support it, rest assured that your bit-perfect audio will remain at 100% of its original quality.