Audio multitasking in iOS4

[Skipp]

I just downloaded the latest update for Audioforge, an iPhone audio editor. It included the ability to play audio in the background so I thought I'd test this out to see if I could record in time to a backing track. Much to my surprise I was able to paste a mono mix of my current Multitrack DAW project into it and set it looping in the background. I was then able to fire up nLog and record a melody whilst still listening to the loop in the background. I saved the nLog part in that App and copied and pasted it into Multitrack DAW where I was easily able to sync it with my existing mix.

I may have missed this feature becoming generally available but it's the first time I've been able to compose a part in one App whilst listening to audio from another and it makes the possibility for creating multitrack content soley on the iPhone much more achievable.

The main problem I have at the moment is that Audio forge does not support the Intua Pasteboard so I'm having to post submixes from Multitrack DAW into Monle first and then from there into Audioforge, which is slightly long winded. There is an App called Audioview by the same author that supports both Pasteboards but I don't know if it will run in the background?

Now if Multitrack DAW would run in the background we would really be getting somewhere!

Thought this might be of some interest to anyone else who was as ignorant as I was that this is possible?

Thanks for the great App!

[pwnified]

Background recording might be doable, I've been in contact with some other app makers to try to standardize a format for sharing realtime audio. I'll post here in a couple weeks when things calm down a bit and we get something together.

[Skipp]

Thanks for the reply.

Realtime audio sharing would be fantastic At the moment however I'd happily settle for Multitrack playing in the background. (don't know if that's even possible given the resources that it must use?)

With the introduction of multitasking and fast switching it's actually not a great problem to copy a submix to another App that plays in the background. I just need to find one with that functionality that accepts the Intua Pasteboard.

[pwnified]

I'll look into that as a first step. There is problem with timing though and how to get the recorded audio aligned. I suppose if the other app can start recording on the first played note, and then use a count in and snap to grid in multTrack, it could work.

[Skipp]

Quick clarification, I've now been able to get the standard pasteboard to paste directly into Audioforge so this has simplified my existing workflow and with fast switching it's reasonably practical.

I haven't found timing a problem when recording against an App playing in the background. I tend to be trying to laydown a new part against a loop of less than eight bars. As long as the App you are playing in can record in a linear, rather than looped fashion, it's a trivial process to trim it to the correct size and snap it to position in Multitrack. I suspect however that the nature and length of the content would make some things easier to align than others.

For App to App recording I'd expect both timing and control to be a nightmare!

[jorgren]

Skipp, thanks for the excellent research. I have nLog too, so I am intrigued. I like its arpeggiator; haven't tried to play its keys in a serious way. Your method might make that practical (i.e., play and play and play until I get it right). You mentioned AudioView earlier, which I got for translating between Intua and Sonoma pasteboards. It's not stable enough to be useful, unless he's updated it. But now that more apps are supporting both formats, not a big deal.

Do you think it's safe to update my OS to 4.0 (I have an iPod Touch 3G)? I am very wary of updates because Apple usually breaks or removes more features than they add, and I'd hate to find they've suddenly disabled the dock port audio inputs, or killed the Intua or Sonoma pasteboard.

[Skipp]

I'm using iOS4 and it seems to be working for most of my audio Apps but I wouldn't like to be responsible for anyone else taking the plunge! (you can usually see in iTunes where individual updates are available to make a particular App iOS4 compliant or to use it's new features.)

I've only tested with Audioforge. I don't own Audioview and there was nothing on the website or iTunes to suggest that it has had an update to allow audio to run in the background.

If you do get Apps that support the combination of fast switching and background audio in IOS4 it appears to be genuinely useful.