User:Billw58/Splitting and Joining Tracks

Splitting and Joining Tracks
Using the Track Drop-Down Menu you can: Ed 1Dec11: "Join two mono, left or right tracks into one stereo track" might be ambiguous. Maybe "Join two tracks (any combination of mono, left or right) into one stereo track" instead? Though that is a bit ponderous.
 * Split a stereo track into separate tracks for left and right channels
 * Split a stereo track into two separate mono tracks
 * Join two mono, left or right tracks into one stereo track
 * Peter 2Dec11: A good start Bill. I note that the content here appears to be a direct copy of the stuff that was previously on the Audio Tracks page, so I'm hoping that means that we can simplify the Audio Tracks page by removing the content that we now have here (or will have when this page gets published).  I can't comment much on the techniques involved here but are you covering te complexities that were discussed on the recent (and ongoing) forum thread on Waveform Display: http://forum.audacityteam.org/viewtopic.php?f=20&t=61175 ?
 * Bill 02Dec11: Yes, this is a copy of the content from the Audio Tracks page, and yes I'm thinking it would be removed from that page. As for the "complexities" - I've addressed those in a note div. I don't think we want to get into all the permutations and my advice (as you can see) amounts to "don't do it".
 * Peter 2Dec11: I see.  Those "complexities" in the forum thread discussion were certainly making my head spin - if anything I'd make your note div advice stronger.

Here is a stereo track:
 * [[image:Split_Before.png|Stereo track before splitting into two separate tracks]]

After selecting "Split Stereo Track" from the Track Drop-Down Menu we get separate left-channel and right-channel tracks:
 * [[image:Split_Stereo_After.png|Stereo track after splitting into left and right tracks]]

After selecting "Split Stereo to Mono" from the Track Drop-Down Menu on the original stereo track we get two separate mono tracks:
 * [[image:Split_Mono_After.png|Stereo track after splitting into two mono tracks]]

Selecting "Make Stereo Track" from the Track Drop-Down Menu of the upper track of a pair of mono, left or right channel tracks (in any combination) will combine those two tracks into one stereo track. The upper track will become the left channel of the stereo track and the lower track will become the right channel regardless of their current designation as mono, left or right. In the example below, two mono tracks are about to be combined into one stereo track. The result of this operation will be to re-create the stereo track as shown in the image above.
 * [[image:TDDM_MakeStereo.png|Two mono tracks about to become one stereo track, with track drop-down menu pulled down to show option]]

When joining two single-channel tracks into one stereo track be aware that: Because of this, it is recommended that when you intend to join two single-channel tracks into one stereo track using Make Stereo Track that you leave the gain and pan settings of the two tracks at 0 and do not apply an envelope to either track.
 * Any gain and pan settings applied to the lower track will be retained until any adjustments are made to the gain and pan settings of the new stereo track
 * Any gain and pan settings applied to the upper track will be applied to the stereo track
 * Envelopes will be retained for the left and right channels of the new stereo track but any further envelope adjustments will be applied to both channels simultaneously which may give unexpected results

Reversing stereo channels
To quickly reverse the left and right channels of a stereo track:
 * Select Split Stereo Track
 * Drag the lower of the two resulting mono tracks above the upper track
 * From the Track Drop-down Menu of the upper track select Make Stereo Track

Applying equalization to one channel of a stereo track
Assume that you have a recording where one channel is "muffled" - lacking in high frequencies compared to the other channel.
 * Select Split Stereo Track
 * Click in the Track Control Panel of the muffled track to select it
 * Choose Effect > Equalization and apply the appropriate equalization curve to the track
 * Listen to the result - if it is not right, choose Edit > Undo Equalization and try a different equalization curve
 * When you are satisfied with the result, select Make Stereo Track from the Track Drop-down Menu of the upper track

Reducing the "width" of a stereo track
Assume you have a recording of a drum kit where the stereo spread of the kit sounds unnatural. The high hat sounds like is coming from the right speaker only and the floor tom from the left speaker.
 * Select Split Stereo to Mono
 * Adjust the pan control of the upper track to 70% left
 * Adjust the pan control of the lower track to 70% right
 * Listen to the result and adjust the pan controls until you get the effect you want
 * Select the two tracks
 * Click in the Track Control Panel of the upper track, then shift-click in the Track Control Panel of the lower track
 * Choose Tracks > Mix and Render
 * The two tracks are mixed and rendered into one stereo track
 * Note that if you had instead selected Make Stereo Track from the Track Drop-down menu of the upper track you would have lost your pan settings