WHAT YOU NEED TO KNOW ABOUT DOUBLE TRACKING VOCALS
What is Double-Tracking?
One of the most sought after qualities for an audio recording to possess is strength and fullness of tone. In all but a few niche examples, the more power and sonic weight a part carries, the better results in the mix and mastering stages. Because the human voice can be easily overpowered by the strength and clarity of electrified guitars, booming drums, and loud keyboards, one of the most commonly used and effective techniques when recording lead vocals is the process of double-tracking.
Why? History and Famous Examples
When audio recording was in its infancy, recordings were made live in a room with all acoustic instruments. Amplifiers and modern PA systems didn’t exist, so the loudest instruments a singer competed with were drums or horns. This was mitigated by placing the singer closest to the mics with the loudest instruments in the back. By the 1940s, technologies had changed and artists such as Les Paul and Mary Ford were tinkering with ways to get a better lead guitar and vocal sound. After hundreds of experiments, they hit upon the first double-tracking technology called “sound on sound”, which involved playing the first part back on acetate disc while recording the same part with it, as close to perfectly in tune and in time as possible. The result was “How High The Moon”, the first recording to have double-tracked vocals and lead guitar. In this recording, Mary Ford sang harmony with herself.
How High The Moon – Les Paul & Mary Ford (1951)
In the 1950s, Buddy Holly used double tracking (and other harmonies) to bring his singles to the next level. This popularized it in Rock n Roll.
Words of Love – Buddy Holly (1957)
As the ’50s gave way to the ’60s, bands like The Beach Boys and The Beatles used double-tracking vocals on most of their early hits. It’s subtle and you’re not supposed to totally notice it, but if you listen closely you can hear what’s going on.
Here is a double-tracked take of “If I Fell” by The Beatles. It has all the music removed and is just John and Paul’s vocal tracks. The beginning is just John double-tracked. Listen to that precision. But notice it isn’t perfect or sound like “one take”. It’s not supposed to. That’s the beauty of double-tracking.
If I Fell (vocals solo’d) – The Beatles (1964)
Re-Record the 2nd Take Organically:
The idea is to sing the doubled part as exactly perfect to the first take as possible. Since the human voice is fallible (unlike a synthesizer) and can’t be perfectly in tune with itself, as hard as one tries, the doubled vocal contains a slight chorus effect that strengthens the sound and helps it cut through the mix.
Step one: Sing the first take with an idea of exactly how it goes. The more familiar you are with the melody, the more you practice it, the easier it will be to double.
Step two: Sing the second take as close to exactly as you did the first. Some engineers prefer to have the vocalist sing to their first take so they can hear and adjust. In this way, you can take 3-5 passes in a row and later choose the take that best matches the original take. Many vocalists find it easiest to execute with one headphone off and one on, so you can hear your new take and not get lost in your voice in the original.
Another method used is to not let the vocalist hear the take and just run them on 5 takes of the part. Later, in post, the vocalist and engineer/producer can decide which two sound best together. This latter technique requires a more experienced vocalist with thicker skin.
Simulating with ADT
Since The Beatles were using double tracking on almost everything, it took up a lot of recording time and expensive tape. This led to Ken Townshend designing an electronic method to achieve the same effect, called Artificial Double Tracking (ADT). This effect takes advantage of tape delay and creates a similar effect in real-time, so you only have to track the main vocal take. Now DAWs like ProTools have plugins designed to emulate the analog machines that created this super common shortcut to more present, thicker vocals.
When Not To Double Track
Double tracking vocals on huge rock songs or loud arrangements is really just a matter of industry-standard, so it’s used widely and for a variety of styles, sounds, and artists. But when it comes to quieter, acoustic, or more intimate, styles of songwriting it isn’t always necessary for vocals. In those situations, double-tracking or not becomes more of a question of aesthetics. It won’t help a stripped-down 50s folk style record feel intimate, or an old-timey rag-time jazz ensemble sound authentic, but it can add 60s shine or psychedelic presence to anything you happen to be mixing if you want to push the envelope and not sound so predictable.
One More Word on Double Tracking Vocals
Whether you use the technique in its usual setting or tinker with it on your next experimental demo, double-tracking is something an engineer should be comfortable with employing and coaching a vocalist to achieve. As a vocalist, it’s something that can be practiced at home with the simplest DAW/USB microphone set-up. It has helped to create some of the best sounding recordings of all time, so if your vocal lead is a little thin or that guitar solo isn’t shining as bright as it should, whether you spend the time nailing it organically or use ADT plugins, double-tracking is always worth the effort.