Editing Windows Media Audio (section)

==Sound quality==
:''See [[codec listening test#Results|codec listening test]] for a table of double-blind listening test results.''

Microsoft claims that audio encoded with WMA sounds better than MP3 at the same bit rate; Microsoft also claims that audio encoded with WMA at lower bit rates sound better than MP3 at higher bit rates.<ref name="wmmusic">{{cite web|url=http://www.microsoft.com/windows/windowsmedia/music/default.aspx|title=Windows Media: Music|website=[[Microsoft]]|url-status=live|archive-url=https://web.archive.org/web/20060415235414/http://www.microsoft.com/windows/windowsmedia/music/default.aspx|archive-date=2006-04-15}}</ref> [[Double blind]] listening tests with other lossy audio codecs have shown varying results, from failure to support Microsoft's claims about its superior quality to supremacy over other codecs. One independent test conducted in May 2004 at 128&nbsp;kbit/s showed that WMA was roughly equivalent to [[LAME]] MP3; inferior to AAC and Vorbis; and superior to [[ATRAC3]] (software version).<ref name="rjamorim">{{cite web|last=Amorim|first=Roberto|url=http://www.rjamorim.com/test/multiformat128/results.html|archive-url=https://web.archive.org/web/20090123124822/http://rjamorim.com/test/multiformat128/results.html |archive-date=2009-01-23|title=Results of Multiformat at 128&nbsp;kbit/s public Listening Test}}</ref>

Some studies concluded:
*At [http://www.rjamorim.com/test/32&nbsp;kbit/s/results.html 32&nbsp;kbit/s],{{Dead link|date=August 2019 |bot=InternetArchiveBot |fix-attempted=yes }} WMA Standard was noticeably better than LAME MP3, but not better than other modern codecs in a collective, independent test in July 2004.
*At [http://www.hydrogenaud.io/forums/index.php?showtopic=50888 48&nbsp;kbit/s] {{Webarchive|url=https://web.archive.org/web/20140708014541/http://www.hydrogenaud.io/forums/index.php?showtopic=50888 |date=2014-07-08 }}, WMA 10 Pro was ranked second after [[Nero AG|Nero]] HE-AAC and better than WMA 9.2 in an independent listening test organized and supported by Sebastian Mares and Hydrogenaudio Forums in December 2006. This test, however, used CBR for WMA 10 Pro and VBR for the other codecs.
*At [http://www.microsoft.com/windows/windowsmedia/forpros/codecs/comparison.aspx 64&nbsp;kbit/s], WMA Pro outperformed Nero HE-AAC in a listening test commissioned by Microsoft but independently performed by the [[National Software Testing Labs]] in 1999. Out of 300 participants, "71% of all listeners indicated that WMA Pro was equal to or better than HE AAC."{{citation needed|reason=No working link to the actual study|date=January 2016}} However, a September 2003 public listening test conducted by Roberto Amorim found that listeners preferred 128&nbsp;kbit/s MP3 to 64&nbsp;kbit/s WMA audio with greater than 99% [[Confidence interval|confidence]].
*At [http://www.hydrogenaud.io/forums/index.php?showtopic=35438 80&nbsp;kbit/s] {{Webarchive|url=https://web.archive.org/web/20140708054803/http://www.hydrogenaud.io/forums/index.php?showtopic=35438 |date=2014-07-08 }} and [http://forum.hardware.fr/hardwarefr/VideoSon/MP3-WMA-AAC-OGG-qualite-kbit/s-evaluation-sujet-84950-1.htm 96&nbsp;kbit/s], WMA had lower quality than HE-AAC, [[AAC-LC]], and Vorbis; near-equivalent quality to MP3, and better quality than [[Musepack|MPC]] in individual tests done in 2005.
*At [https://web.archive.org/web/20100214134736/http://www.listening-tests.info/mf-128-1/results.htm 128&nbsp;kbit/s], there was a four-way tie between aoTuV Vorbis, LAME MP3, WMA 9 Pro and AAC in a large scale test in January 2006, with each codec sounding close to the uncompressed music file for most listeners.
*At [https://web.archive.org/web/20070927173254/http://www.edn.com/article/CA307865.html 768&nbsp;kbit/s], WMA 9 Pro delivered full-spectrum response at half the bit rate required for [[DTS (sound system)|DTS]] in a comparative test done by [[EDN (magazine)|EDN]] in October 2003. The test sample was a 48&nbsp;kHz, 5.1 channel surround audio track.

===Criticism of claimed quality===
Microsoft's claims of WMA sound quality have frequently drawn complaints. "Some audiophiles challenge Microsoft's claims regarding WMA's quality", according to a published article from EDN.<ref name="EDN Internet Radio"/> Another article from MP3 Developments wrote that Microsoft's claim about CD-quality audio at 64&nbsp;kbit/s with WMA was "very far from the truth".<ref>{{cite web |url=http://www.mp3developments.com/article4.php |title=Lossy Audio Formats |publisher=MP3Developments |access-date=2007-08-16 |url-status=live |archive-url=https://web.archive.org/web/20070815110114/http://www.mp3developments.com/article4.php |archive-date=2007-08-15 }}</ref> At the early stages of WMA's development, a representative from RealNetworks claimed that WMA was a "clear and futile effort by Microsoft to catch up with [[RealAudio]] 8".<ref>{{cite web |url=http://www.streamingmedia.com/article.asp?id=6637 |title=Codec Rivalry Spurs Development |publisher=streamingmedia.com Codec |access-date=2007-08-16 |archive-url=https://web.archive.org/web/20071015090021/http://streamingmedia.com/article.asp?id=6637 |archive-date=2007-10-15 |url-status=dead }}</ref>

Microsoft has sometimes claimed that the sound quality of WMA at 64&nbsp;kbit/s equals or exceeds that of MP3 at 128&nbsp;kbit/s (both WMA and MP3 are considered near-[[Transparency (data compression)|transparent]] at 192&nbsp;kbit/s by most listeners). In a 1999 study funded by Microsoft, [[National Software Testing Laboratories]] (NSTL) found that listeners preferred WMA at 64&nbsp;kbit/s to MP3 at 128&nbsp;kbit/s (as encoded by [[MusicMatch Jukebox]]).<ref>[http://www.microsoft.com/windows/windowsmedia/compare/audiocompare.aspx Microsoft's summary of the study] {{webarchive|url=https://web.archive.org/web/20071024035924/http://www.microsoft.com/windows/windowsmedia/compare/audiocompare.aspx |date=2007-10-24 }}. [http://www.nstl.com/reports/Final%20MSAudio%20Report.pdf Full report from NSTL] {{webarchive|url=https://web.archive.org/web/20071128082513/http://www.nstl.com/reports/Final%20MSAudio%20Report.pdf |date=2007-11-28 }}.</ref> 

Both MP3 and WMA encoders have undergone active development and improvement for many years, so their relative quality may change over time.