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.


Sent from my smartphone. 

Willy Foobar <> 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

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.


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