<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">There seems to be some 10 KHz signal, but it's like -75 dB.<span class="Apple-converted-space"> </span>I doubt you</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">can hear that, since the rest seems to be around -10 dB.<span class="Apple-converted-space"> </span>I can't hear it.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div></blockquote><div><br class="webkit-block-placeholder"></div><div>You are right I just checked with different headphones, and I don't hear it with those -- only my sony mdr-7506 do reproduce the artefact, and trust me, with them it does not sound like a -60dB noise ! (those headphones are very very sensitive to high frequencies)</div><div><br class="webkit-block-placeholder"></div><div>For people who may want to check if they hear the difference, I have put two wav files here</div><div><a href="http://gruntthepeon.free.fr/test/m.wav">http://gruntthepeon.free.fr/test/m.wav</a></div><div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">and</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica"><a href="http://gruntthepeon.free.fr/test/m2.wav">http://gruntthepeon.free.fr/test/m2.wav</a></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">they were obtained from the same mp3 file with a "default" and a "64bit" version of mpg321</div></div></div></div><div><br></div><div>Julien</div></body></html>