[MPlayer-users] looking for the correct syntax of a certain command

[Christian]

Hi all,

I found out that mplayer supports an *equalizer* option natively.

The command     "mplayer -af equalizer=0:0:0:0:0:0:0:0:10:10 
sound-file.wav"       generally works fine. It produces much crisper audio.

But: *Some* wav-files have a sample-rate that is too low for that 
process. Terminal says:

"[equalizer] Limiting the number of filters to 8 due to low sample rate."

So the equalizer option has no effect.

On http://mplayerhq.hu/DOCS/HTML/en/MPlayer.html I found an interesting 
comment:

"Sample Rate Conversion:

If the audio sample rate in the original file is not the same as 
required by the target format, sample rate conversion is required. This 
is achieved using the -srate option and the -af lavcresample audio 
filter together."

This is the example they give:


"DVD:    -srate 48000 -af lavcresample=48000"

Now I´m not dealing with a DVD here but a mere audio-file. So I tried 
two different commands:

"mplayer -srate 44100 -af equalizer=0:0:0:0:0:0:0:0:10:10 
sound-file.wav"         and
"mplayer -srate 44100  -af lavcresample=44100 -af 
equalizer=0:0:0:0:0:0:0:0:10:10 sound-file.wav"

Both work equally well and produce an exit code of "0". And both have 
the desired effect of making the equalizer kick in.

So my question is:

What do you think, which syntax is the correct one and which should I use?

Thanks in advance for your help.
Many greetings.
Rosika

P.S.:
my system: Linux/Lubuntu 20.04.2 LTS