Which audio format truly has the best sound quality?

Question

I've been to every website, and I've heard again and again that FLAC (Free Lossless Audio Codec) has the best sound quality AND it compresses the file. But I'm wondering if there is a format with better sound quality. (I don't care about anything else.) I have heard that WAV is good, but is the sound quality better than FLAC? And are there any others that are better?

Solution 1

First of there are two types of compression, lossless and lossy.

Lossless compression means you will get identical copy of your source when decompressed. In audio this means no quality loss during compression.

Example of lossless compression: FLAC, ALAC, Monkey Audio, Dolby TrueHD, DTS-HD MA, etc.

Lossy compression on the other hand will result quality loss. It works by discarding data to achieve better compression.

Example of lossy compression: AAC, MP3, Vorbis, Dolby Digital, DTS, etc.

WAV files containing PCM audio are not compressed audio. So no quality loss there either.

Whether or not you can tell (perceive) this quality loss depends on several factors, your ear, your audio setup (speakers, headphone, etc), encoding parameter of lossy codec, etc.

Solution 2

"I have heard" - the gold standard for audio quality is in how it sounds. And in many cases, the hardware you use and the combination matter. If you must know foobar 2000 has a great A/B testing function you can try to decide for yourself.

Flac is lossless. Many people can't tell the difference between high bitrate mp3 and flac (I can on my home listening gear, but even then its not a massive difference). Wav is uncompressed audio. Flac is losslessly compressed audio. For most definitions of lossless, and decoders that arn't completely garbage, the output should be the same.

Practically speaking at the same given sample rate without any other bottlenecks FLAC will sound exactly the the same as the wav file. For that matter, any lossless audio file should sound exactly the same as any other lossless audio file.

Passed through a spectrum analyzer you can see what sound is - and using that

A quick visual inspection suggests the output is identical

With smaller file sizes. You can find the sample UI used here - its the 48mhz clip from Jean-Michel Jarre's Equinox analysed with spek. The nice thing with analysis like this is your audio gear dosen't make a difference . The lossless "raw" PCM file, and the flac file I converted from it are for all intents and purposes identical when played back

There's been a push towards higher sample rates but arguably, beyond a certain point the improvements are marginal. Chances are, the sort of folks who demand 96 or 192 khz audio files also have silver cables, carefully burnt in power cords made of hand selected materials and other forms of audiophoolery. Its just an excuse to try to sell you hardware that dosen't perform any better.

Even with different sample rates - 48khz is common, and while some sources promise higher sample rates - people who write audio codecs suggest it might actually sound worse. The frequencies you 'miss out' on are not audible, and your sound output is going to have issues playing them.

So, lossless, at a reasonable bitrate on decent hardware is going to sound the best.

For most people, flac's a safe bet for archival use (since its compressed and lossless so you can convert it), though high bitrate lossy music is more sensible.

Solution 3

The quality of an audio codec is determined by how close its output is to the original source. The quality can only ever be as good as the source.

FLAC is a lossless codec which means its output is an absolutely perfect, 100% identical copy of the original. It produces 100% perfect quality and it is impossible to get any better.

PCM WAV is also a lossless codec and therefore has identical quality to FLAC and every other lossless codec.

There is no difference in quality between any lossless codecs and none are "better" than any other quality wise. The differences lie in file size, capability, and compatibility only.

Comments

[Admin]

I see you already got downvote(not me :) ), I encourage you to read policy of this site. Such question will return a lot of opinion based answers that will mislead you and all others who will read it in a future. Regarding your question - try this

[Admin]

FLAC and WAV are identical in terms of quality

[Admin]

@yoyo_fun No. They are not. See my reply below.

[Admin]

@FleetCommand so what people refer to as WAV format when talking about ripping Audio CDs is actually the LPCM audio format contained in a WAV container ?

[Admin]

You didn't address WAV at all.

[Admin]

WAV/RIFF is a container format, yes, but for the purposes of this discussion it's probably pretty safe to assume LPCM (audio format 0x0001) and not something funny like μ-law or ADPCM.

[Admin]

@Bob Er... why not? And what makes ADPCM funny?

[Admin]

WAV/RIFF certainly can contain metadata, even if it's not common to include much beyond basic information on the included format.

[trumpet205]

That's because PCM WAV is not compressed. It is incorrect to call it lossless compressed.

[Admin]

(it's also true that many files labelled .wav don't include a format header at all, requiring the program using them to already know what format the data is in. don't mistake that as part of the specification.)

[Admin]

Yes. But the OP explicitly asked how WAV compares. So... (Please note that I actually upvoted your reply, so whether you add WAV to it or not, it is still a good answer.)

[Admin]

@FleetCommand Because audio CDs basically standardised music on LCPM. FLAC is also targeted at music, and generally contains (compressed) PCM data. The others are rarely seen (μ-law and ADPCM in particular are primarily for telephony use). Great that you mention that it's a container, thus answering the literal question, but you've also completely the intent of the question (re: wav), IMO.

[Admin]

@Bob There is not a single hint in the question that it is about music. Furthermore, have you seen Audio Compression Manager's interface? It just lists those cryptic formats, not giving a clue that ADPCM mustn't be used for music.

[trumpet205]

Fair enough, edited it.

[Tetsujin]

+1 ...& if you're going to - a) squeeze it out of your computer's 50 cent Realtek into a couple of plastic boxes from BestBuy, b) plug your phone into the car system or c) listen on headphones whilst commuting; you're never going to appreciate the difference from a 128-bit mp3 anyway ;)

[Thalys]

Oh, even with fairly decent gear, the difference between 320cbr/vbr and flac is minimal in my experience. My main reason for preferring flac is that its an excellent archival format. Wav... makes no sense for the end user to me, whatsoever.

[Tetsujin]

Indeed. I can tell the difference on my studio monitors... just. On my not hugely expensive home theatre/hifi system I'd struggle. In the car etc... who would care? I find many of these 'what's the best sound' questions fail to grasp that to most people, on ordinary equipment or on the move, they will simply never be able to tell the difference.

[Keltari]

while this answer is correct, I want to add one thing. In the end, the quality depends entirely on the source. If it is a microphone or an output of another device, you are limited to its ability to pickup and play sound. A poor quality source will produce a poor quality sound, regardless of file format.

[Makkou]

IMHO, this answer should get neither an upvote nor a downvote. It is chatty and wanders off topic. On the other hand, a lot of effort has gone into it.

[Thalys]

On the contrary - while the question seems simple, it answers "whether flac is worse than wav" - and gives a way to visually confirm it, and attempts to talk about what these "better" formats are, and why its worse. Its a long answer with no TLDR cause the question isn't quite as simple as it seems.

[tvdo]

The easier test rather than visually comparing spectrums is to simply start from the losslessly-compressed file as a source and convert it to uncompressed PCM, then compare the uncompressed data. Those should be bit-for-bit identical (run a binary diff on them).

[Makkou]

@JourneymanGeek Brevity isn't negligence. It is an art.