Ask A Sound Guy

I know that’s a lofty claim, but Soundflower really can Rewire your Mac’s audio in brain-bending ways.  Soundflower, btw is a little app developed by Cycling ‘74 (anyone heard of Max/MSP?).  

It adds both a 2 and 16 channel bus to your “sound card” listings.  What that means is, anywhere you can decide where to route audio – in DAW’s, in Core Audio, in Screen Capture utilities like iShowU.  For example: If  I really wanted to record a voice chat I had over Skype, then I could route the output of Skype (Skype>Preferences>Audio) to Soundflower (2ch) like this:

Audio Preferences in Skype

Then I could throw open an audio recorder – Lets use Audacity because it’s simple.

Audio Preferences in Audacity.

Then I go to the menu Audacity>Preferences>Audio I/O tab.  Set the Recording Device to Soundflower (2ch) and leave the Output device Built-in Output (or your normal sound card hooked up to speakers).  Hit Okay, and record enable a track.  

There, you’ve successfully rewired Skype into Audacity.  It’s just as easy to do with any other recording application that doesn’t use proprietary hardware (sorry, this won’t work with Pro Tools because you have to use the I/O on the physical hardware).

But what about apps that don’t let me choose the audio output like Firefox?  Well that’s easily remedied because you actually can choose the output of Firefox – it’s just not in a Firefox menu.  Go to your computer’s System Preferences>Sound tab>Output.  You’ll see Soundflower listed there as your options right along with Internal Speakers, Headphone Output, and any other USB/Firewire Interface you have hooked up.  

Select Soundflower (2ch) as your output here, and all the sounds any apps going through your computer’s core audio (the system preferences) will be playing their audio into the Soundflower stereo bus. Now to hear it, just open up you’re recording software and select the input as Soundflower (2ch) and monitor that input on a track. 

You should be realizing by now, that you can do all sorts of funky pirating with this, but that’s not why I want people to know about Soundflower – and I’m not going to explicitly described how to do it either.   

But take this one step further than lowly pirating and there’s lots of options that open up.  You setup an MC on skype with his own mic in L.A. and route audio in of Skype with the Soundflower (16ch) bus and Skype’s Out to the Soundflower (2ch) bus. Play the beat back for him into skype and record his rhymes through skype over the voice chat.  Yes, the quality won’t be great and it’ll be subject to intense compression due to streaming, but isn’t it cool that you can do it?

Anyway, you’re all resourceful, so I’m sure you can think of lots of cool things to do with this – like recording the audio from your Alladin Dvd into Garageband so you can finally get the REAL version of “A Whole New World” with all the sound effects and ambience left in.  Right?  

(BTW there are a lot of programs that do things like this on macs & PC’s, but I’ve yet to find one as elegant and easy as Soundflower.)

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