DSD vs FLAC vs WAV [What's better? 2021]
At first glance, the difference between DSD and FLAC audio formats is outstanding. Except for some limitations and features of each format, the comparison is very same to DSD / DSF / DFF / SACD vs FLAC / WAV / PCM. Many endless discussions, that format is the best, are there. But this question has no single answer. Read the explanation and FAQ by audio software developer Yuri Korzunov why it so, about comparison FLAC versus DSD sound quality and watch the video to study details below.
HD audio file conversion
What are DSD and FLAC and WAV and SACD and others
To understand, which is better DSD or FLAC, we should understand what they are.
FLAC (WAV, PCM)
FLAC (Free Lossless Audio Codec) is an audio file-container format and compression method of recording or stream.
WAV also is file-container, that can contain compressed and uncompressed PCM and DSD in DoP.
FLAC, WAV, AIFF are lossless PCM implementations.
DSD (SACD, DSF, DFF)
DSD (Direct Stream Digital) is an audio recording or stream format by Sony, Philips. DSD sample rate is significantly higher than FLAC and other PCM (WAV, AIFF, etc.). And bit depth is reduced from FLAC's 16/24/32 bit to minimal 1 bit for Direct Stream Digital format. 1 bit is too low even for 2.8 MHz and higher frequencies. How 1-bit is allowable in Hi-Res audio read below.
DSD may be stored as DoP (DSD over PCM) into a lossless PCM container (FLAC, WAV, AIFF, etc.).
DSD has implementations: DSF, DFF, SACD optical disk, SACD ISO file (image of SACD optical disk), DoP.
To be technically correct we compare implementations of both formats.
DSD vs FLAC sound difference
The most popular DSD and FLAC comparison is listening to a single album by the same label in two different formats.
However, DSD and FLAC (PCM) sound quality comparison is a complex matter. Because there are many variables:
- recording, mixing, postproduction,
- level of recording loudness,
- playback software,
- hardware (player, DAC).
A sound difference between DSD and FLAC may be produced by a variance between these factors.
All these variables are defined by an implementation. Thus, it is impossible to say exactly: what sounds better DSD or FLAC. Because each case should be studied apart.
When we try to compare FLAC / WAV / AIFF ... other PCM and DSD album variants at home, it is easy to get sound difference due to 0.5-2 dB variance between DSD and PCM circuits or software processing, in instance.
The variance may be considered as almost unlistenable as level difference. But we can get some impression of sound or audio quality difference.
So, before tests, it is necessary to compensate the level variance between DSD and PCM outputs to 0.1 ... 0.2 dB difference, approximately. It allows avoiding an imaginary sound difference due to various levels.
Otherwise, we risk getting "better quality" for louder DAC or DAC mode.
In instance, one person has louder PCM output and likes FLAC more. But other person has louder DSD output and prefer DSD. As a result, they can discuss "what is better" indefinitely.
And it is only one of several control goals, when the listening test is performed. And there are many details, that are invisible at first sight.
Read about hi-fi blind tests >
To DSD and FLAC format comparison:
Modulation
The main difference between FLAC and DSD is a kind of musical signal modulation. Or kind of analog signal coding to digital form. Further, we consider the difference in the modulations.
Bit depth
Bit depth of DSD is reduced to 1 bit. But it causes huge quantization error noise and a low signal-noise ratio. To improve the ratio, noise energy is pushed out of the audible frequency range.
Sample rate
Bit depth reducing demands frequency range reserve for noise energy pushing. The range reserve may be added by a higher sample rate.
DSD sample rates: DSD 64, DSD 128, ...
FLAC sample rates: up to 384 kHz.
Useful audio band
The range reserve causes useful DSD audio band reduction, comparing [sample rate]/2 band of PCM.
DSD is intended for audible range transmission. As rule, DSD64, has minimum noise levels in the band below 20 ... 24 kHz. Above this band noise level grows with frequency.
Higher DSD sampling rate allows expanding this low-level noise band.
The aforementioned figures depend on implementation.
Size compression
DST (Direct Stream Transfer) is a size compression method for DSD audio stuff. It is implemented in DFF and SACD ISO files. DSF has no size compression ability.
FLAC format is intended for size compression primarily. But there is the opinion (without objective evidence, known for the author), that computing for FLAC uncompressing causes additional electromagnetic interference of a computer (or a playback device), that degrades the sound. To avoid unpacking, uncompressed FLAC is used. The FLAC is used because it contains a metadata standard way.
FLAC file-container also can contain MQA-compressed audio stuff. Such FLAC may be played back without MQA-decoding.
DAC inner work
As rule, PCM DAC is intended for FLAC playback, is based on a sigma-delta modulator and demodulator. The demodulator is a low-frequency filter.
DSD DAC can contain the filter only.
Text metadata
Text metadata (album and track names, performer, etc.) contains in SACD ISO, DSF, FLAC files standard way. DFF has no standard metadata support.
Artwork metadata
SACD ISO and DFF don't support artwork metadata standard way. FLAC and DSF both can contain multiple artworks (album cover, band photo, etc.)
Frequently Asked Questions
Is FLAC the best format?
FLAC is one of a lossless formats, that are better by sound quality than lossy ones. Free Lossless Audio Codec provides size compression. But the sound quality is the same WAV, AIFF and other lossless formats. Also, FLAC allows a maximum sampling rate and bit depth limitation (32 bit, 384 kHz).
However, .flac file may contain lossy compressed stuff coded in format another than Free Lossless Audio Codec.
Is WAV lossless?
Yes. WAV is a lossless audio format.
Do FLAC files sound better?
FLAC files are lossless. And we can be sure, that FLAC fully keeps sound quality of a source digital signal. DSD and PCM are just different modulations and it is not a matter for coded musical signal in the digital domain (when no processing, of course). However, ADC and DAC implementations may make difference between PCM and DSD formats. Read more...
Is DSD better than PCM? Is DSD better than FLAC? Is DSD better than PCM?
What is better DSD or PCM (FLAC, WAV, AIFF, others) depends on:
- recording;
- implementation of recording and playback equipment.
Lossless PCM files (WAV, FLAC, AIFF, etc.) have similar sound quality. However, they support different resolution audio.
Is DSD audio worth it? Is DSD better?
Theoretically, DSD allows solving issues of an analog filter of a digital-to-analog converter. Practically, it is a matter of recording quality and equipment distortions. Read more...
What is DSD files?
DSD files (.dsf, .dff, .iso [SACD ISO], .flac/.wav [DoP]) contains audio data in Direct Stream Digital format. Read more...
Does conversion FLAC to WAV lose quality?
When audio processing is not applied, WAV converted from FLAC provides absolutely the same sound quality. See video...
Are DSD files better? Is DSD better than PCM?
Despite DSD give some audio-equipment-design advantages to achieve better sound quality, only audio device implementation defines the actual sound quality of a device. How to look for the best quality of your audio system read here...
Which is better AIFF or FLAC?
AIFF is a more flexible format (almost non-limited audio resolution, but some limitations with file length more than 4 GBytes). FLAC has better metadata compatibility with music devices and software. AIFF or FLAC is no matter of sound quality. Read more...
Is FLAC or WAV better? Is WAV better than FLAC?
WAV is a more universal format:
- almost non-limited audio resolution,
- file size limitation (4 GBytes), which may be solved via RF64 format.
FLAC has better metadata compatibility with music devices and software. Both formats have the same sound quality. Read more...
What is DSD512?
DSD512 is a sample rate 22.6 MHz=44100 Hz * 512. Read more...
What is DSD music?
DSD music is music provided in DSD format. Some DSD music samples are recorded in DSD and distributed without editing. Read more...
What is DSF?
DSF format by SONY is one of Direct Stream Digital file formats. Read more...
Is SACD better than CD?
It depends on recording and equipment. Read more...
Is MQA better than DSD?
Many factors impact to sound difference between MQA and DSD: implementation of recording and playback equipment, mix and postproduction quality of a recording. Also, it needs to remember, that MQA is lossy. But we can compare only implementation of given audio systems. Because the small losses may not be a "bottleneck". Read more...
What is DSD audio?
DSD audio is a method of coding an analog signal in a digital form. Read more...
Is DSD the best audio format?
In theory, DSD audio system reduces number of required components. However, given system design is a matter for actual distortion level. Quality of recording (including mixing, postproduction) impacts to listenable experience.
Read details:
What does WAV mean?
WAV (Waveform Audio File Format) is a format of audio files. Read more...
Yuri Korzunov (Audiophile Inventory's founder),
March 09, 2021 updated | since February 04, 2018
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