Logic Pro X - Video Tutorial 17 - Isolate or Remove Vocals from a Song with Phase Cancellation Video Lecture | Logic Pro X: A Practical Hands-on Course - Music

hello this is music tech help guy
welcome to episode 17 of my Logic Pro 10
video tutorial series in this episode we
are going to pick up a little bit where
we left off in episode 16 and we will
talk about phase cancellation and a
couple cool tricks that we can do with
phase cancellation so the first scenario
I'm going to show you today is how you
can take a recording that has vocals and
instruments and we are going to use
phase cancellation to cancel out the
instruments while leaving the vocals
isolated and the second scenario is the
exact opposite we're going to take a
recording with vocals in an instrument
and we are going to remove the vocals
just leaving the instruments so we can
have an instrumental version of the song
so the first scenario is how can we take
a recording with vocals just like this
one right here we've got coos two
acoustic guitars layered and then vocals
in red and then on top I have an
instrumental version of the song with no
vocals now in order to to do this you
need to have an instrumental version of
the song I realize it's not always you
know it's not always the case you know
is gonna be able to do that but uh in
order to do this to basically isolate
the vocals from the this recording here
we need to have an instrumental of the
song it's just this the way it goes and
the best way to have an instrumental of
the song is to actually get the studio
instrumental version of the song just
the same bounce as the studio did just -
the vocals now what phase cancellation
does is we're going to invert the phase
of one of these tracks the instrumental
track actually actually it doesn't
really matter but we're going to invert
the phase of one of the tracks and
anything that matches from one track to
the next track is going to be cancelled
out so for instance my guitars will be
cancelled out here my guitar what my
guitars here will cancel out the guitars
here but since there's no vocals up here
in the instrumental version
the vocals will be left intact down here
not perfect but intact enough to have an
isolated vocal recording so let's listen
what we've got here the top one is just
instrumental
so that's the instrumental version and
this is the version with vocals I'm just
gonna start a little further into the
song here to be saved from chaos and
stirring this world
let's build to silence the hatred
so these two recordings are virtually
identical to each other with the
exception that the bottom one has the
vocals in it in the top one doesn't and
also the other thing that's important is
that they are perfectly aligned with
each other not even a millisecond off
not even a couple samples off they need
to be perfectly aligned with each other
so it helps to bounce the instrumental
from the same bounce range the bounced
the real version of the song with vocals
so I'm going to do is I'm going to
double-click on the instrumental track
here and I'm going to open the file
editor the same editor we used in the
previous video and all we have to do is
hit command a to select all go to
functions invert and we are going to
invert the phase of the instrumental
track now since we're not in also since
we're not inverting the phase of the
vocal track the guitars are going to
cancel each other out I'm going to have
one out of phase and one in phase and so
all the guitars are going to cancelled
out leaving the vocals exposed so let's
start about measure 5 and you'll notice
that when I press play you're not going
to hear anything so you can even see the
signal here but we're not hearing
anything and here's the vocals to be
saved from the chaos and staring this
world I can even solo one of the tracks
and press play and we'll start hearing
the guitars again
but as soon as i unsolo it uh again the
that phase cancellation takes over and
the guitars are cancelled out a beam of
blood spill to silence the hatred held
the other thing that's important is that
both of the tracks are centered in the
stereo field or at least in the same
place in the stereo field both of them
are centered if I were to start to move
the pan here on one of the tracks you'll
actually start to hear the phase
cancellations stop taking effect and
you'll start to hear one of the tracks
again so if I press play here do besaid
so you start hearing it as I adjust the
pan because the two waveforms are the
two tracks are not aligning at the same
place in the stereo field okay so that's
how you can isolate vocals from a
recording it requires two things a good
instrumental track studio quality
instrumental track plus the original
song and you have to line them up and
then invert the phase of one of them so
the next scenario I want to show you is
how you can take a song that has vocals
and instruments like this one and how
you can use phase cancellation to
basically create your own instrumental
version of the song and the way that
works is we are going to basically
cancel out the left and right channels
leaving the center chain the center of
the recording which is usually going to
be the vocals not always but usually
going to be where the lead vocals are so
I don't even need the instrumental track
for this because essentially that's what
we're trying to do are trying to create
our own instrumental track so let's say
hypothetically we don't have the
instrumental track I'm just going to
mute and hide that the way this works is
we need to split this stereo file it's a
stereo file there's a left and a right
channel we need to split the stereo file
into two separate mono Channel
and that we're going to invert the phase
of one of the channels while leaving the
other one intact now unfortunately in
logic you can't just invert the phase of
one channel at a time if you're working
in a stereo track and there's also no
easy way to just drag your stereo region
onto two mono tracks like you can do in
Pro Tools or like an audacity so we
actually end up having to do is we
actually have to bounce this recording
as a multi mono or a split file so
basically what does splits the left and
the right channel into two separate
files and that well then what we're
going to do is we're going to drag these
back into logic on to mono audio tracks
and then we'll invert the phase of one
of them so all I did is I selected the
range I want to bounce with the locators
and hit command B to get to my bounce
window here I'm going to make sure that
my file type is not interleaved
interleaved will actually combine the
left and right channels into one file I
want to make this split so I have a
separate left and right channel and
there we go that's all I have to do it's
going to hit bounce tell it where to go
save it to the desktop here and I'll
just call it sure I'll just keep it
output one and two it's bounced let's go
look at our desktop and you'll see that
there is an output one and two left and
an output one and two right now there's
a little problem here logic is too smart
for its own good sometimes and if I drag
one of these left even just the left
file into logic it'll actually try to
pair them up again it'll recognize that
the two files are a stereo pair so I'm
gonna do is I'm going to rename one of
them just left and the other one right
and so it shouldn't recognize them as a
stereo pair anymore because they don't
have the same file name so I no longer
need my my original track up here it's
going to mute and hide this one as well
and what I'm going to do is I'm going to
create two mono audio tracks
and you can double check to make sure
they're mono by looking at their input
here you'll see a single circle rather
than two circles so the top one will be
left the bottom one will be right and so
I'm just going to return cycle mode off
drag the left one in drag the right one
in and you can also double check that
they didn't get imported as stereo by
looking at the top corner of the
top-left corner of the region if you
just see one circle you know that that's
a mono file on a mono track rather than
a stereo file on a stereo track all
right so now the last step all we have
to do and by the way if we play this
right now it's just going to sound like
a less wide version of the original
recording because we've gotten rid of
any sort of stereo variants in the
stereo field so I play this it'll just
sound like the same recording we had
before and even though I get to the
vocals you hear at the vocals as well
so I'm going to do is I'm going to
double click on my right track here go
to my file editor go to functions and
invert the phase of that track and so
now my right channel is out of phase a
hundred actually a hundred and eighty
degrees out of phase is called with the
left channel and when I press play now
we're just going to hear the guitars
without the vocals
so the vocals would be playing here
normally
now just like before if I change the
position of one of these channels in the
stereo field with my pan knob here
you'll actually start to hear the vocals
again so the both tracks have to be
Center or in the same place in the
stereo field for this to work and so
then once you're done if you want to you
know make up you want to render your
instrumental version all you have to do
is do the command B thing again to
bounce save it as a new file and I leave
an instrumental version of the track all
right so that's how you can isolate
vocals and how you can create
instrumentals using the file editor in
Logic 10 now in all honesty this isn't
going to work very well on all songs I'd
say maybe about 70% of the time it's
going to just it's just gonna fail it's
not going to work at all or not very
well now the first scenario I did if you
can find a quality Studio instrumental
it'll work pretty much without a hitch
almost every time the second scenario
though where you're trying to you know
cancel the two channels out and then
just have vocals remaining that's a
little trickier to do because most
modern mixes have some sort of a plug-in
on the vocals that widen it in the
stereo field or maybe there's backing
harmonies backing vocals doubled vocals
reverb you know pretty much all reverb
plugins are in stereo so even if your
vocals are you know just by themselves
there's no backing harmonies in their
pan Center if you're using reverb at all
well the the reverts basically causing
some variance in the left and right
channel and therefore it's not going to
work as well so for the second scenario
to really work you've got to have the
vocals pans dead center with no added
effects that are widening it in the
stereo field we also have to be aware
that the second scenario cancels out
everything in the center of the mix not
just focal so although lead vocals tend
to be in the center of the mix most of
the time sometimes there's certain
instruments that are in the center of
the mix like bass bass
our kick drum snare drum so sometimes
you'll find that those instruments get
canceled out as well now the reason why
it turned out so perfectly in this video
is because I chose a song that was
really simple I just had vocals dead
center no added effects or reverb and
then I had two guitars one pan mostly
left one pan mostly right again with no
effects on them so it turned out really
well because the song was so simple if
you're dealing with a song that's more
texturally rich and complex it's not
quite going to work out as well so what
I've done is I've posted a link in the
description so that you can actually
download my instrumental and vocal
version so you can try this out on your
own so I hope you enjoyed the video and
thanks again for watching