How to remove vocals from a song, and WHY it works
TLDRThis video script explains how to create karaoke mixes by using the concept of phase cancellation. By inverting the phase of one stereo channel and playing it alongside the original, the common elements, often including the lead vocals, are canceled out, leaving mostly the instrumental track. This technique works well for songs where the vocals are centrally mixed, common in pop music from the last 40 years.
Takeaways
- 📝 Phase cancellation is a principle used to remove vocals from a song by playing two identical waves out of phase with each other.
- 📝 Inverting one wave effectively turns it upside down, making it a mirror image of the original, which results in silence when played together.
- 📝 Stereo music typically has the lead vocals centered, balanced between the left and right channels, while other instruments are spread across the stereo field.
- 📝 By extracting the left and right channels into separate files and inverting one, you can cancel out the central vocals and isolate the instrumental track.
- 📝 The process involves using audio editing software to manipulate the phase of one channel and then overlaying it with the other.
- 📝 In most pop music from the last 40 years, the lead vocal is mixed centrally, making it a candidate for phase cancellation to create karaoke tracks.
- 📝 Reverb or echo effects on vocals might remain after phase cancellation, as they can be applied in a stereo field separate from the dry vocal track.
- 📝 A faint ghostly vocal track might still be audible in the background, which can serve as a guide vocal to help with singing along.
- 📝 This method works with any song where the lead vocal is mixed down the middle, which is common in modern music production.
- 📝 Creating a karaoke mix from a song is a fun way to illustrate the concept of phase cancellation and can be done with most songs from the past 40 years.
Q & A
What is phase cancellation and how does it relate to making karaoke mixes?
-Phase cancellation is an acoustical concept where two identical waves that are out of phase (one is inverted) can be played together, resulting in total silence because they cancel each other out. This is used in making karaoke mixes by inverting one of the stereo channels of a song, which cancels out the vocals that are usually centered in the mix, leaving mostly the instrumental track.
How does inverting a wave affect its phase?
-Inverting a wave effectively turns it upside down, changing all positive values to negative and vice versa. This alteration is referred to as a phase inversion, which is crucial for phase cancellation as it aligns the wave in such a way that it can cancel out another identical wave when played together.
Why is the lead vocal often mixed straight down the middle in stereo music?
-The lead vocal is typically mixed straight down the middle in stereo music to ensure it is clearly audible and balanced in both the left and right channels. This central positioning makes it easier to isolate and remove using phase cancellation techniques for creating karaoke versions of songs.
What is the first step in creating a karaoke mix from a stereo song?
-The first step in creating a karaoke mix from a stereo song is to extract the left and right channels into separate mono files. This allows for the manipulation of each channel individually to remove the vocals.
What happens when you layer the left and right channels without inverting one?
-When you layer the left and right channels without inverting one, the song will sound the same as the original stereo mix because both channels are playing their respective parts simultaneously.
How does inverting one channel and playing it with the other help in removing vocals?
-Inverting one channel and playing it with the other causes the common elements, such as the lead vocal which is usually centered, to cancel out due to phase cancellation. What remains are the elements that were not centered, like the instrumental parts.
Why might you still hear a faint version of the lead vocal in the karaoke mix?
-You might still hear a faint version of the lead vocal because effects like reverb or echo, which are often applied to the vocal, can create a stereo image that is not perfectly centered. This means that not all of the vocal's sound is canceled out when inverting one channel.
What is a guide vocal and why is it useful in a karaoke mix?
-A guide vocal is a faint version of the original lead vocal that remains in the mix. It is useful in a karaoke mix because it can help the singer hit the right notes and remember the song's structure without overpowering their own singing.
Can this phase cancellation technique be applied to any song?
-This technique can be applied to most songs where the lead vocal is mixed straight down the middle, which is common for many songs produced in the last 40 years. However, it may not work as effectively if the vocal is not perfectly centered or if effects are used that create a stereo image.
What role do instruments play in the phase cancellation process when creating karaoke mixes?
-Instruments that are not centered and are distributed across the stereo field will not be canceled out when one channel is inverted. Instead, they will remain audible, providing the instrumental background for the karaoke mix.
Outlines
🎶 Creating Karaoke Mixes with Phase Cancellation
This paragraph introduces the concept of phase cancellation and its application in creating karaoke mixes. Phase cancellation occurs when two identical waves are inverted and played together, resulting in silence as they cancel each other out. The process is illustrated using a stereo mix of a song, where the left and right channels are extracted and one is inverted. When played together, the common elements (usually the lead vocals) are canceled out, leaving the instrumental parts, thus creating a karaoke version of the song. The example given is Katy Perry's song, where her lead vocals are mixed down the middle, and by inverting one channel, they are effectively removed, leaving a mix that can be sung over with minimal vocal interference.
Mindmap
Keywords
💡Phase Cancellation
💡Karaoke Mix
💡Stereo Mix
💡Invert
💡Lead Vocal
💡Multitrack Session
💡Phase
💡Sine Wave
💡Guide Vocal
💡Reverb
💡Instrumental
Highlights
Creating karaoke mixes is fun and illustrates the concept of phase cancellation.
Phase cancellation occurs when two identical waves are inverted and played together.
Inverting a wave turns its negative parts positive and vice versa.
When inverted waves are played together, they create silence due to phase cancellation.
Stereo music has a left and right channel that can be extracted into mono files.
By layering the left and right channels, the original song can be heard.
Inverting one channel and playing it with the other cancels out the common elements.
This technique removes the lead vocal which is usually mixed straight down the middle.
Instruments are typically distributed across the stereo field, not in the middle.
The phase cancellation method leaves the instruments but removes the central vocals.
Some faint vocals might remain due to stereo reverb or echo effects.
The remaining faint vocals can act as a guide vocal for karaoke purposes.
This method works with most songs produced in the last 40 years.
The technique can be used to create karaoke mixes for personal enjoyment.
Phase cancellation is a fundamental acoustical concept with practical applications.
The process involves editing audio files to extract and invert channels.
This method provides a way to enjoy singing along with songs without the original vocals.
