How to remove unwanted sounds and background music from a vocal sample

Posted in Music Production on March 13, 2011 by Xyla

When you are looking for vocal samples to use in your industrial/trance/whatever electronic music, more often than not the sample will have unwanted background sounds or music.  There is a simple process I use for removing those sounds.  I use Logic on Mac OS X for my audio production, however I’m sure my technique can be adapted using different software if you are so inclined.

First, you will need to work with the original 5 channel audio, so that means ripping from a DVD.  If the TV show or movie is not available in 5 channel audio then unfortunately this technique won’t work.  Fortunately this is a rare problem unless you are sampling something really old.  For this silly example we will use a clip of Tuvok in a battle situation on Star Trek Voyager.

Here is the original audio downmixed to stereo.  As you can hear, there is a lot going on.

The next thing you will need to do is figure out which VOB file contains the section of audio with your sample and then strip the individual channels out of the AC3 audio.  I use a program called a52decX which can be found here.

The vocals will be in the center channel, but usually the music and other sound effects will also be in this channel, albeit quieter.  This is the center channel by itself.  Often times the extra sounds are quiet enough you can just use it as is, especially if your song has lot of layers playing over it, but in this example it’s not much better than the downmixed stereo version.  The left-front and right-front channels should contain the unwanted sounds and music, and we are going to use those two channels to cancel out the sounds in the center channel.

The left and right front channels sound like this.

Create a new project in Logic with at least 3 audio tracks.  We will be working in mono since the vocals are mono.  Now add the left-front, right-front and center channels each to their own audio track.  Create a bus object and set the output of both the LF and RF tracks to the bus.  Set the bus output to Output 1-2 along with the center track.  Set the locators roughly around the section with the sample.

Now here’s the key… put a Gain plugin (under Utility) on the bus and turn on Phase Invert.  Remember, make sure all your tracks and objects are in mono mode.  Play it and see how it sounds.

Because the sounds in the center channel are going to be a different volume than in the left and right front channels, it will probably not sound right… in fact it may not sound any better, or it may sound worse.  The trick here is to manually adjust the gain on the plugin until it is cancelling the unwanted sounds as much as possible.  It will most likely be impossible to remove them completely, but usually you can get them so quiet they will be impossible to hear in the final mix as long as there is some kind of ambient sound playing alongside it.  In this example the best setting turned out to be a gain of -4.8.

And now, the final result.

Bounce it out, load it up into your editor of choice, normalize and trim it.  You are ready to throw it in your song.  With a little EQing, delay, and reverb and you get this sillyness.


Second album

Posted in Music Production on March 12, 2011 by Xyla

As many people have noticed, I have not released any new music since my album Esoterica in 2007.  That’s really a long time.  I can’t even remember all the things that happened to me since then.  Some of it was just normal life stuff, some of it… not so normal.  Several times I have tried to make progress on a second album, but most of the tracks I experimented with didn’t get past the concept stage.  I did finish one song a couple of years ago but for some reason it still hasn’t been released.  In theory it will be on the next Shaman Films compilation.  Since then I got very involved with iPhone/iPad game development, which is very time consuming.  Recently though, I have turned my attention back to Logic Pro and become serious about my music.  Honestly I wasn’t sure if this would ever happen again.

Things are coming together quite nicely.  Some of the tracks I had started a year or two ago I have returned to with fresh ideas, and I have written some new ones from scratch as well.  iPad development is still taking a lot of my time, but I suspect it won’t be too long before my second album is finished, I’d say by summer.  The style is pretty similar to my last album, but more refined.  It definitely sounds better in my opinion… but then if I thought I wasn’t exceeding my past work, it would mean I was doing something wrong.  One thing that is different is I have returned to the classic use of vocal samples (as in, ripped from TV and movies), something I purposely left out of all the songs on Esoterica.  Currently I have the first track of the album completed, and 3 more half completed.  The rest have been started, though I may change my mind and replace them with something different by the time the album is finished.

As things progress I intend to post updates.  At some point I also plan on putting up a real website at my URL, which currently just points to my very dusty MySpace page.


Time to try a new blog site, but will I stick with it?

Posted in Uncategorized on March 10, 2011 by Xyla

Welcome to my new blog.  I’ve been notoriously bad at posting to my LiveJournal in the past, and ever since Twitter I have completely abandoned it.  It’s just as well, as most of my LJ posts had about as much substance as a single tweet anyway.  However, on occasion I’ve wanted to write something more substantial, and ghost-town LJ seemed like a waste of time, so I got over it.

I can’t decide on a name for my blog, so I’ve temporarily jokingly called it the Blog of Death.  We’ll see if I stick with this… if so I’m sure I will be able to come up with a real name.