Hi Willy,
2013/3/6 geoff <[email protected]>: > Sure Willy..almost certainly it's phase cancellation; this is the property > of physics employed widely in voice removal software. Two identicle waves of > opposite phase will cancel each other out ..the closer to unity amplitude > they get the more cancellation. hth. Yes I think so too. > > g > > > Sent from my smartphone. > > > Willy Foobar <[email protected]> wrote: > Hallo dear MuSE team, > > > when I generate a wav-file there > is an audible difference between mono and stereo output (from PCM wav files) > > I use crazy_frog_-_axel_f.mid, that can be found at > http://freemidi.org/directory-1079 > > I cannot send this midi file directly due to copyright issues. > > > > timidity crazy_frog_-_axel_f.mid -OwM -o mono.wav > timidity crazy_frog_-_axel_f.mid -OwS -o stereo.wav > timidity crazy_frog_-_axel_f.mid -Ow -o default.wav > > there is a hearable difference between mono.wav vs. stereo.wav. > The same difference for default.wav (this is a stereo output) > > The stereo sounds a little bit more smooth and has more reverb. > > > > > > > Even using the option --preserve-silence there is the same difference. > Even, when I split the two stereo channels into two separate wav files, > the audible difference does not change. > > Is this a result of the mid notes that uses stereo interaction? > I did not find any controller events that deal with pan or something > similar. > > Does anybody have an idea, where this difference comes from? > I want to produce teh same sound in mono. Do I understand you correctly that this happens regardless if MusE is involved, just timidity? As Geoff says this is probably phase cancellation. Probably some of the samples timidity uses are stereo samples. Simply put, stereo samples mixed down to mono can never sound the same, mono carries less information. The biggest issue is probably frequency parts in the left and right channel that when mixed together will cancel out. The extreme would be when the same sine would exist in both channels but negative phase in one of them. The result will be silence. This area is much deeper than I can give a good explanation of. I think it is safe to say that it is to be expected that in many cases the mono will not sound as good as the stereo version. Regards, Robert ------------------------------------------------------------------------------ Symantec Endpoint Protection 12 positioned as A LEADER in The Forrester Wave(TM): Endpoint Security, Q1 2013 and "remains a good choice" in the endpoint security space. For insight on selecting the right partner to tackle endpoint security challenges, access the full report. http://p.sf.net/sfu/symantec-dev2dev _______________________________________________ Lmuse-developer mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/lmuse-developer
