<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - LFE channel not synthesized properly" href="https://bugs.freedesktop.org/show_bug.cgi?id=95021#c24">Comment # 24</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - LFE channel not synthesized properly" href="https://bugs.freedesktop.org/show_bug.cgi?id=95021">bug 95021</a> from <a class="email" href="mailto:tanuk@iki.fi" title="Tanu Kaskinen <tanuk@iki.fi>"> Tanu Kaskinen</a> <pre>Based on IRC discussions, it seems likely that we will revert the default configuration to what it was in 6.0. That is, we won't synthesize LFE channel at all by default. The solution that I thought we'd do was to sum the low-pass filtered audio from all channels, instead of averaging it like we do now. That, however, can cause clipping in the LFE channel. The clipping can be avoided by lowering the volume, but it has its problems too. When converting 5.0 content to 5.1 channels, the absolutely safe thing would be to divide the amplitude of all channels by 5. Since that's pretty big reduction in volume, we could also do an empirical test on some collection of content and see how much the volume has to be reduced in practice in order to avoid clipping in 99% of cases. If we reduce the volume on 5.0 -> 5.1 conversion but not when playing 5.1 content, that means that 5.1 content will play louder than 5.0 content, which is not really acceptable, so we would have to reduce the volume the same amount in all cases. Alexander reported that Windows 10 doesn't synthesize the LFE channel (nor the center channel) when playing stereo content to a 5.1 device. The front channels just get copied to the rear channels, and also the amplitude is halved.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are the assignee for the bug.</li> </ul> </body> </html>