Vocal doubling might be the most common mixing technique we see in modern vocal mixes. It allows us to take a single vocal source and double it to create a more exciting stereo image. With a vocal doubler, we can make a copy of an audio signal and pan it the opposite direction to create width.

Of course, as with most effects on the market these days, vocal doubler plugin options are in no shortage, and many come loaded with additional effects and features that make them stand out.

In this guide, I'm going to take you through some of my favorite vocal doubler plugins on the market today, so you can start applying this technique to your mixes.

What Is the Doubling Effect?

When doubling a lead vocal, it's worth noting that it can either be done manually or automatically .

From a manual standpoint, a vocalist will actually go about recording vocal doubles in the studio before panning them in opposite directions to get real width.

On the other hand, when it comes to the automatic doubling effect or ADT, a singer will cut a single lead vocal take and run it through a plugin to get doubled vocals. Back in the day, this was done through the use of tape machines, wherein signals were "doubled" using slight pitch changes and delays.

Engineers were finally able to get similar results to real double-tracked vocals.

Luckily, you don't need to get your hands on a hefty or expensive tape machine to get the same effect. Everything you need to go about doubling vocals can be found in your DAW.

1. Waves Abbey Road ADT

One of my absolute favorite vocal doubler plugins is the Abbey Road Reel ADT from Waves.

The original ADT or "artificial double tracking" technology came about in the early 1960s, when a few Abbey Road engineers came up with a solution after a complaint from John Lennon, who was sick of double-tracking his vocals during the recording process.

They derived a unique method in which two tape machines would be played at once, though with a slight delay between each, in essence, doubling the signal.

The team from Waves decided to take the old technology and put it in plugin form. Now, anyone who wants to get their hands on the original sound of ADT can.

The plugin certainly has a special sound to it, and it allows you to pan the source and the double in any way you please, so you can choose how wide you want your stereo image to be. There's also a cool drive control, allowing you to add a bit of distortion or saturation to either one or both of your vocals.

Beyond that, Reel ADT takes it a step further by including Varispeed and LFO settings, allowing users to determine both how fast the second "tape machine" is moving, as well as the speed of the LFO based on the particular project.

Not only do I often find myself using this on vocals, but it's also one of my favorites when I want to take a single guitar recording and spread it into stereo.

2. Sonnox VoxDoubler

Sonnox VoxDoubler comes as two distinct plugins, allowing you to take on multiple vocal doubling tasks at once. The great thing about this plugin is that it offers a very natural doubling effect, great for when you want it to sound like you recorded another vocal track.

The user interface is also sleek and easy to use, offering few parameters and large knobs.

The overall plugin is divided into two, including the Widen and the Thicken plugin.

The Widen plugin takes a single voice and creates two separate mono voices, panning them right and left of the original signal. It's the best choice for anyone who needs to take a mono vocal performance and give it some stereo width. There are also plenty of onboard controls for tone, width, and depth, as well as a mix control for parallel processing.

As for the Thicken plugin, this takes a stereo doubled voice and puts the original signal on top, making it seem as if the person sang the exact same part two times. You'll find the exact same parameters on the Thicken plugin that you'd find on the Widen plugin, though instead of the width knob, they give you a stereo spread control.

Overall, I'm a huge fan of Sonnox plugins, and I truly can't think of a better vocal doubler plugin for those who want to create a natural doubling effect.

3. UAD MXR Flanger/Doubler

The UAD MXR Flanger/ Doubler plugin offers an emulation of some of the most legendary analog gear on the market, providing two effects — flanging and doubling.

It's the sound of the '70s wrapped up in a single, easy-to-use plugin. If you're a fan of Van Halen, you'll likely recognize the effect right away, as Eddie was known to use the MXR Flanger/Doubler unit a lot in his recordings. The same goes for Dimebag Darrell, the guitarist of Pantera.

Luckily for us, UAD took all the wonderful characteristics of the MXR Flanger/Doubler and wrapped it up in plugin form with Dunlop approval.

The plugin gives you the ability to switch back and forth between the flanging and doubling effect, as well as adjust the dry and wet ratio, the oscillation speed, and the width. You can even flip the phase and sync your effect up with the host tempo.

The Manual Knob is one of my favorite features on this plugin, as it allows you to manually adjust how the effect swings. It's a nice cherry on top for when you want to get experimental. I often find myself using the Mix knob on this plugin too, blending it in with my dry vocal tracks to get the best of both worlds.

Overall, if you're looking for an analog-style vocal doubler that offers two separate plugins in one, I can't think of a more exciting plugin than this one.

4. Soundtoys Microshift

I've long been a huge fan of Soundtoys and Microshift is one of the best plugins in their bundle, even beyond vocal doubling. The plugin is based on two old-school hardware pitch shifting units — the AMS DMX 15-80s and the Eventide H3000.

The plugin works by widening the original signal using your choice of three distinct styles, each of which you can adjust with different delay and detune settings for a wide range of unique doubling tones. There's also a mix knob at the end, allowing you to dial the effect in parallel.

Even beyond using this plugin as a vocal doubler, I often find myself using it to add subtle width to traditionally mono instruments, such as bass guitars and snares.

When it comes to Soundtoys plugins, I'm a pretty biased follower. They all sound so good, and most of them offer an analog sound quality that's hard to get elsewhere. Plus, it's one of the easiest plugins on this list to use, meaning you can dial in a final sound in a pinch.

It's also worth noting that when you purchase Microshift, you get the smaller and more CPU-friendly version of the plugin, Little Microshift, for free.

5. Waves Vocal Doubler

Though this classic Waves plugin is nothing new, as it has been on the market for quite some time and the user interface could certainly benefit from a little modern love, it is still one of the most capable tools for vocal doubling out there. Pair that with its harmonization features, and you have an incredibly versatile yet budget-friendly modulation tool. 

On the upper section of the plugin, you'll find dedicated displays and parameters for managing double tracking, stereo width, detuning, and equalization, giving you complete control over the tone of your dry and doubled vocals.

You also have the flexibility to duplicate the signal up to four times, and since the controls work for each voice, you can make precise adjustments to each of the doubled vocal elements. 

Some of the controls include panning, detuning, octaver, feedback, gain, delay (ranging from 0 to 100 ms), mod rate, mod depth, and on/off.

One of the main downsides to Waves Doubler is that it does not have a Mix knob, meaning that if you want to use parallel processing, you'll have to use an auxiliary track and route your dry vocals to it.

6. Antares Duo

Antares has long been known as the developers for auto-tune, though the company also happens to make one of the best vocal doubling plugins on the market. Duo is a pretty straightforward piece of software. You get simple doubling parameters that allow you to dial in the volume and panning of both the doubled vocal and the dry vocal, as well as change the pitch variation, timing variation, vocal timbre, and vibrato.

One of the unique things about this plugin is that it also asks you for the vocal range of the dry vocal that you are working with, so that it can provide you with a cleaner doubled vocal with fewer artifacts. You'll find a couple of different options, including Soprano, Alto/Tenor, and Baritone/Bass. There is also an option for instruments if you're doubling something like a synthesizer or guitar.

The pitch variation adjusts the amount of random pitch variation that you'll get between the two vocals, while the timing variation adjusts the delay between the two. You can then use the vocal timbre control to make the doubled vocal either sound lower or higher in pitch, as well as the vibrato control to give the doubled voice a bit of natural vibrato.

Overall, it's a very straightforward plugin for doubling vocals with a simple interface to match.

7. Acon Digital Multiply

Acon Digital Multiply is another free plug-in designed to give you doubled vocals in a pinch. The team from Acon recently updated the plugin with a few improved EQ features, allowing you to have better tonal control over your new stereo doubled voice.

However, the central focus of this plugin is the ability to dial in multiple voices with independent frequency modulation controls. The amplitude modulation is very clean, meaning you'll get a more natural chorused effect that doesn't sound so 'swooshy.'

I don't often find myself using this one on lead vocals, however, just because I think there are some better vocal doubler plugins out there. However, if I even want to thicken up background vocals quickly, it's a great tool.

Doubling Down On Your Vocals

When it comes to doubling vocals, I always recommend tracking a few takes, as you'll get the most natural sound by doing so. With that said, once in a while, using a vocal doubler plugin can be a nice way to get a similar effect or an effect that's completely out of this world.

Hope you enjoyed the list!