| From matt mitchell
| Fri, 13 Jul 2007 08:59:00 +1000
| Subject: [Audacity-help] Help!
| how can i change i a mono file into a stereo file?
You can make a mono track stereo thus:
1 Select the whole track by clicking on the Track Panel (where
the mute/solo buttons are)
2 Duplicate it to another track (Edit > Duplicate)
3 Click the Track Popdown Menu
on the upper of the two tracks (by the downward pointing arrow) and
click "Make Stereo Track"
You can instead simply click Project > New Stereo Track (or Tracks > Add
New.. > Stereo Track in 1.3.3). The presence of the empty stereo track
will make the file "stereo" when exported. With either of the two procedures,
the content of left and right channels will of course be identical and the
stereo track will sound identical to the mono track.
If you are looking to add an artificial stereo effect to a mono track you can
try some "tricks" to give the track more sense of space.
First, duplicate the mono track thus:
1 Select the whole track (CTRL + A or click in its Track Panel where
the mute/solo buttons are).
2 Duplicate it to another track (CTRL + D or Edit > Duplicate)
These are some ideas to try on the two tracks:
1. Select one track by clicking in its Track Panel and Effect > High Pass
filter, and then repeat for the other track using the same cut off point,
but use Effect > Low Pass filter. Used judiciously, you can move
higher-frequency sounds to one track, and lower-frequency sounds to
the other track.
2 Use the Time Shift Tool top left <---->
-Zoom in until you can see 3 decimal places on the ruler (i.e., to
the order of milliseconds)
-Shift the lower track to right by somewhere between 10
and 40 milliseconds.
At the moment you will still have a mono track when you export the two
tracks on screen, as mixing two mono tracks still makes a mono track. To
export a stereo track, you just have to move the pan slider -........+ on
the Track Panel of either so it's at anything but the centre, then CTRL + A
to select both tracks and Project > Quick Mix (Tracks > Mix and Render in
Alternatively, click the Track Popdown Menu on the upper of the two tracks
and click "Make Stereo Track". That is the equivalent with the other method
of panning the top one 100% left and the bottom one 100% right and then
Quick Mixing, except it's much easier. Naturally, once the content of the two
channels is different (e.g. if you had shifted the frequencies around), "make
stereo" has a much more pronounced panning effect than making a small
change on the panning sliders, and can lead to a "hole in the centre" effect on
only two tracks. Of course you may even feel in some circumstances that using
the Time Shift Tool or frequency filtering alone gives a pleasant enough
separation effect without making the track stereo.
Note that if you make a stereo track by duplicating mono tracks, the resulting
track may distort because you're combining the volume of two tracks. To check
for distortion, play the tracks together and check on the green VU Playback
Meters that the meter bars are not reaching the far right-hand edge of the
scale, and so bringing on the red clipping (distortion) indicators to right of the
Meter. If this happens, move the -....+ gain sliders on each track to left by the
same amount, until the clipping no longer occurs. If the Meters is not visible,
go to the Interface tab of Preferences and check "Enable Meter Toolbar", or in
1.3.3 click View > Toolbars > Show Meter Toolbar.
There are also things you can try to give an effect of greater space without
making the mono track into a stereo track.
One of these is to add reverberation. Audacity uses GVerb to add reverberation
(Effect > GVerb, look for it underneath the divider).
Here are some tips on using GVerb:
You can also try this "stereoizer" VST plug-in if you are on Windows:
You will need Audacity's VST Enabler:
Put the unzipped stereoizer.dll in your Audacity Plug-Ins folder along with the
unzipped vst-bridge.dll from the Enabler zip folder. Then restart Audacity and
Stereoizer will appear in the Effect menu underneath the divider. Typically the
path to Audacity's Plug-Ins folder is:
Outbound message virus free.
Tested on: 7/13/2007 3:19:25 AM