Talk:Crossfade Tracks

Archive discussion

Gale 06Jan15: IMHO we need some help here for users who start from a stereo track, likely the more common case than mono. We should give them some help on how to split the track and slide the resulting lower part underneath. What is the recommended way? Click in the waves at the intended end of the first song, SHIFT + K then Split New?

• Steve 06Jan15: What are you getting at? What has this got to do with splitting tracks? Would it be sufficient to include a picture in which the crossfade is applied to a stereo track?
• Gale 06Jan15: That might help, but the problem I see is that there is no guidance on how to use this effect when you have a single stereo track. That is, when I say "a stereo track", that is the singular article. Do you understand now?
• Steve 06Jan15: I imagined a typical use to be: the user has imported 2 or more tracks, they align them with the time shift tool, crossfade the tracks, export their "mix", or that they had recorded multiple tracks...
• Peter 06Jan15: I'm expecting that a lot more users (like me) will be using this to crossfade a pair of stereo tracks or songs to effect a smooth transition between the songs or to effect a repair to interrupted audio. Splitting a stereo track into two monos and then merging the end of one into the start of the other is most likely to be a comparatively rare usage imo. And yes examples with stereo tracks might be clearer - but there are many places in the Manual where we use a mono track in preference to a stereo one in order to save space and for clarity of the example. I have used this effect, working from this page, to repair a recording interrupted by clicking in the Timeline. I found the page easy to follow (made a couple of tweaks and suggestions to Steve for clarity).

  Sure we could provide a second example with splitting stereo and crossfading the resulting two mono tracks, but I really don't see the point. Indeed I think it would introduce complications on this page that are unnecessary.

  One thing for sure - this new effect (even with a few wrinkles, mainly wrought by Nyquist limitations) is much easier to use than the "Cross Fade In/Out" effects that it replaces. For a start this one "does what it says on the tin" the previous two didn't.

• Gale wrote on -quality 07Jan15: ... We can thrash out the details, and where,in the Manual ednotes, I suggest.
• Gale wrote on -quality 07Jan15: A common example would be a recording of an album side you have already made, or a recording of an internet show that has ads or chat you don't want between the songs. Note that our docs are quite biased towards recording multiple songs on one track, for otherwise good reason.
  • Peter 07Jan15: And note that a crossfade is only one way to deal with these use-cases, others include: delete the unwanted portion and "Repair" the join (which I use a lot on radio broadcasts and webcasts), or patch over the unwanted bit with surrounding similar sound. I did use the Crossfade Tracks approach most successfully recently when I had a webcast that inadvertently got interrupted by a mistaken click in the Timeline, followed by a relatively hast click of the Record button, to restart recording.
• Gale wrote on -quality 07Jan15: The point I am making is that it is not at all obvious what to do if you are starting from a single stereo track containing the songs.
  • Peter on -quality 07Jan15: That is a more than fair point Gale, but I think best addressed in a tutorial or an examples subpage (of this page) rather than in the relatively straightforward documentation page for the effect itself (this page)- which seems fairly clear to me.
• Peter 07Jan15: So, Gale, bearing in mind the recent comments above - if we decide to go for a new tutorial should it be a broad-based "Repair Audio" Tutorial with all three approaches (and maybe others) - or do we just keep it focused on "Repair audio with a crossfade"? in which case it could maybe just be a subpage of this page). In either case I suggest we use stereo tracks in the examples.
  • Steve 07Jan15: If your point Gale is that novice users will need additional help for the use case of selecting parts of one recording (mono or stereo) and crossfading them to create a new mix, or deleting part of one track (mono or stereo) and crossfading the remainder (that is, crossfading parts from one mono or stereo recording / track), then I can see your point. I also agree with Peter that a separate tutorial for such tasks would be a good solution.
    • Gale 10Feb15: I think the essence of what you are describing is already at http://manual.audacityteam.org/man/Creating_a_Crossfade. Extra help there wouldn't come amiss, perhaps in two sub-tutorials, one generalised and one with a specific use case such as repair. But no, the major issue which the mystery shoppers show is more fundamental. They have no idea how to go about the crossfade using Crossfade Tracks when they are starting with *one* track that has separate songs within that one track. I intend to add text for this to Crossfade Tracks, but someone else doing it for review for 2.1.0 would be appreciated. And even better than docs like you describe would be a separate shipped effect that does not require two tracks to work. :=)
      • Peter 11Feb15: Indeed Gale, but this page is documenting a new effect that crossfades between two tracks (not one) as it clearly says in the intro note. It is a valuable addition to the Audacity armoury imo, I've already used it in RL to good effect. We do really have to remember that Audacity is a multi-track editor and is not restricted to operating on single tracks.

        And yes there is some overlap between this page and Creating a Crossfade - but that page is designed as more of a tutorial (along with Fade and Crossfade all this is a bit overlapping, a bit like Topsy it "just growed up") and this page is the direct documentation of an effect (which we must have as we document all shipped effects)

        Yes it may well be useful for some folk for us to create a X-fade that operates on a single track over say a selected region, but the interface would need to be carefully thought out - how, for example would you define the two bits that need fading, how would you deal with potential silence (or audio) between those bits?

        I went off to the Wiki as I thought I recalled something along the lines you are asking for Gale - and indeed there it is Proposal Crossfade]. It's been there a long while too, since 2008 in fact (originated from a GSOC student). All you need to do Gale is to find yourself a developer and get them interested in this, Vaughan is your best bet I suspect, as he is the only one of the current key developers to have actively added his support for that proposal (though I note that Dominic supported the idea too). Alternatively you just have to learn to code Gale ... ;-))

        I actually support the development of such a single track X-fade, just now I encountered an edit of a webstream where it would have benefited. In fact my formal support was long ah=go added to the Wiki proposal.

        And even if we did get that single-track X-fade implementation I think we would still need this one too for those folk that prefer to work in a multi-track environment

        I think it would be fundamentally wrong to add material on splitting a single track to prepare for a crossfade to Crossfade Tracks as you propose Gale, as this page is a page documenting the effect and not a general how-to - and I would strongly oppose such material on this page. If you must add such material then it should probably go in Fade and Crossfade or Creating a Crossfade more likely the latter - or you need to write a whole new tutorial.

        Update: I see that Steve has very recently added such novice advice to Creating a Crossfade. :-)

  • Steve 07Jan15: Gale, is the use case that you have in mind about "repairing audio" as Peter suggests, or about crossfading selected 'songs' from an album, or something else? I think it would be most useful for a tutorial to cover the most general case of crossfading selected regions from one track, and allow the user to adapt the general procedure to suit their specific need.