Editing Super Audio CD (section)

== Sound quality ==
{{see also|High-resolution audio#Controversy}}

Sound quality parameters achievable by the Red Book [[CD-DA]] and SACD formats compared with the limits of human hearing are as follows:

; CD: Dynamic range: 90&nbsp;dB;<ref name="Fries2005"/> 120&nbsp;dB (with shaped [[dither]]);<ref name="xiph"/> frequency range: 20&nbsp;Hz—20&nbsp;kHz<ref name="Middleton, Zak"/>
; SACD: Dynamic range: 105&nbsp;dB;<ref name="Middleton, Zak"/> frequency range: 20&nbsp;Hz— 50&nbsp;kHz<ref name=extremetech2001/>
; Human hearing: Dynamic range: 120&nbsp;dB;<ref name="springer"/> frequency range: 20&nbsp;Hz—20&nbsp;kHz (young person); 20&nbsp;Hz—8–15&nbsp;kHz (middle-aged adult)<ref name="springer" />

In September 2007, the Audio Engineering Society published the results of a year-long trial, in which a range of subjects—including professional recording engineers—were asked to discern the difference between [[high-resolution audio]] sources (including SACD and [[DVD-Audio]]) and a compact disc audio (44.1&nbsp;kHz/16 bit) conversion of the same source material under [[Blind experiment#Double-blind trials|double-blind]] test conditions. Out of 554 trials, there were 276 correct answers, a 49.8% success rate corresponding almost exactly to the 50% that would have been expected by [[Statistical significance|chance guessing]] alone.<ref name="Galo"/> When the level of the signal was elevated by 14&nbsp;dB or more, the test subjects were able to detect the higher [[noise floor]] of the CD-quality loop easily. The authors commented:<ref name="AES"/>

{{ blockquote
| Now, it is very difficult to use negative results to prove the inaudibility of any given phenomenon or process. There is always the remote possibility that a different system or more finely attuned pair of ears would reveal a difference. But we have gathered enough data, using sufficiently varied and capable systems and listeners, to state that the burden of proof has now shifted. Further claims that careful 16/44.1 encoding audibly degrades high resolution signals must be supported by properly controlled double-blind tests.
}}

Following criticism that the original published results of the study were not sufficiently detailed, the AES published a list of the audio equipment and recordings used during the tests.<ref name="mixonline"/> Since the Meyer–Moran study in 2007,<ref name="drew"/> approximately 80 studies have been published on high-resolution audio, about half of which included blind tests. [[Joshua Reiss]] performed a meta-analysis on 20 of the published tests that included sufficient experimental detail and data. In a paper published in the July 2016 issue of the AES Journal,<ref name="reiss"/> Reiss says that, although the individual tests had mixed results, and that the effect was "small and difficult to detect," the overall result was that trained listeners could distinguish between high-resolution recordings and their CD equivalents under blind conditions: "Overall, there was a small but statistically significant ability to discriminate between standard-quality audio (44.1 or 48 kHz, 16 bit) and high-resolution audio (beyond standard quality). When subjects were trained, the ability to discriminate was far more significant." Hiroshi Nittono pointed out that the results in Reiss's paper showed that the ability to distinguish high-resolution audio from CD-quality audio was "only slightly better than chance."<ref name="Nittono"/>

Contradictory results have been found when comparing DSD and high-resolution PCM formats.  [[ABX test|Double-blind listening tests]] in 2004 between DSD and 24-bit, 176.4&nbsp;kHz PCM recordings reported that among test subjects no significant differences could be heard.<ref name="Blech"/> DSD advocates and equipment manufacturers continue to assert an improvement in sound quality above PCM 24-bit 176.4&nbsp;kHz.<ref name="korg"/> A 2003 study found that despite both formats' extended frequency responses, people could not distinguish audio with information above 21&nbsp;kHz from audio without such high-frequency content.<ref name="NHK"/> In a 2014 study, however, Marui et al. found that under double-blind conditions, listeners were able to distinguish between PCM (192&nbsp;kHz/24 bits) and DSD (2.8&nbsp;MHz) or DSD (5.6&nbsp;MHz) recording formats, preferring the qualitative features of DSD, but could not discriminate between the two DSD formats.<ref name="Marui"/>