What’s so Great About Tubes?

If you’re involved in making music, at some point you’ve heard about an audio product that uses vacuum tubes. Typically found in amplifiers, microphones, EQs, and compressors, the sounds created by tube saturation often described as “warm” or “vintage.” But what does that actually mean? What makes tube saturation so special? And how can you get those sounds on your tracks?

Warm models the sound of vintage analog tube saturation and distortion. Now available with Auto-Tune Unlimited.

The History of the Vacuum Tube

Electronic equipment first started being commercially manufactured toward the end of the 19th century. At the time, vacuum tubes were the only components available to control electrical current flow in circuits. Though they were used in every application of electronics, they had serious drawbacks. Vacuum tubes distorted signals and had a tendency to burn out. When the cheaper, more reliable discrete transistor became the standard in consumer electronics in the ‘60s, tubes fell out of favor. Today, audio remains the only application of electronics to still regularly use vacuum tubes.

Old school: the warming glow of vacuum tubes powering a high-end amplifier

New school: The Warm plug-in by Antares delivers authentic tube saturation in your DAW

So why are tubes still used in audio? It’s because those same imperfections that lead to their demise in consumer electronics actually sound good. That’s because tubes exhibit harmonic distortion at lower volumes than transistors. This harmonic distortion is often perceived by the human ear as “warmer,” “thicker,” and generally “more natural.” The truth is, our ears crave complexity more than perfection. And tubes provide that complexity.

While people love the natural sound of tube saturation, vacuum tubes still present the same drawbacks they always have. Namely, they’re expensive, short-lived, and unpredictable to work with. This is where the Antares Warm plug-in comes into play. Warm’s tube modeling emulation offers all the goodness of vacuum tube sound without the restrictions of working with 19th century technology.

horse-drawn buggy and a nightclub

You didn’t take a horse and buggy to the show. So why keep using tubes in your studio?

The Science Behind Tube Saturation

To understand how tube saturation creates harmonic distortion, let’s review a visual representation of the effect in Warm.

First, take a look at the spectral results of a single dry, pure, test tone:

A simple sine tone at about 50 Hz (note that the noise you see below -175 db is inaudible).


Now look at the same tone, but with “Crunch” mode in Warm cranked up:

Notice all of the extra sound and complexity being generated. That’s the harmonic distortion brought on by the modeling of tube saturation found in Warm. On a pure tone, the difference simply sounds like distortion. But on vocals, drums, guitars, and synthesizers, tube saturation can make significant improvements in sonic character.

Recognizing The Classic Tube Sound

Some of the most legendary microphones in history were built with vacuum tubes. The dramatic effects of tube mics are most audible when paired with a singer giving a dynamic performance. Before looking at how to get “that tube sound,” let’s listen to a classic recording that illustrates what tube saturation sounds like.

Listen to the louder notes from singer Gloria Jones in her classic 1965 soul single, “Tainted Love.” This is what  level-dependent saturation on a tube mic sounds like. 

The effect on Gloria Jones’ vocal does indeed sound “warm,” but it also has a little hint of distortion that gives it a visceral, raw vibe. It’s a classic, captivating sound that producers and engineers have been chasing for decades. Luckily, the chase is over. With Warm, it’s easier than ever to get the sound of tube saturation without actual tubes.

Tube Warmth in a Digital World

If you want to get the warm, natural sound of tube saturation you have two options. The first is to invest in an all-tube signal chain: microphones, eqs, compressors, and amplifiers. You should expect to pay somewhere north of $10,000 for an entry-level tube setup. (That said, the best tube mics on the market start at $10,000.)

Your second option is a lot less painful—and a lot more powerful. True to its’ name, Warm delivers those authentic, vintage tube sounds to your tracks without the expense or hassle of working with physical tubes.

Tube saturation made easy with the Warm plug-in

Ahhh, that comforting tube glow!


To hear how it works, let’s start with a short vocal sample. First we’ll listen to it dry, then with some Warm added in Velvet mode (for a more subtle saturation). Drive is set to 10, so it’s definitely an audible distortion (especially when the singer hits a longer/harder note at the end of the phrase). In this example, we’ve adjusted the output attenuation to make up for the increase in gain (you’ll want to do this depending on how much Drive you apply).

Listening to the isolated vocal, you can definitely hear the extra harmonic distortion added by the tube saturation in Warm. Listening in the context of a track, you can really hear why that counts. Notice how much better the vocal sits in the second two repetitions: with Warm on vs. the first half, where the vocal is dry:

While tube saturation is great on vocals, it’s equally as desirable on other sounds. Tube amps are prized for the “breaking up” tones you get when you really crank them. This effect can easily be replicated using Warm with the Crunch model and Drive cranked all the way up:

Warm lets you add authentic tube saturation to any sound, and it’s efficient enough to use on multiple channels in your mix.

Beyond the Limits of Physics

As a digital plug-in, Warm has a distinct advantage over tubes because it’s not limited by the physics of the natural world. This is most apparent in the Omnitube mode. Typically, Warm works just like a normal tube amp: the signal will distort when the level exceeds a clipping threshold. With Omnitube engaged, however, everything is subject to tube distortion. That means everything gets crunched, not just the louder parts and the transients. It’s a dramatic effect, and one that you can only get in a digital environment.

Check out Omnitube on both an Acid synth and a 909 drum kit. The first few measures are dry, the next few are wet. The difference isn’t just audible—it’s dramatic.

You’ll probably notice a kind of “glue” effect with Omnitube. This sounds incredible, especially for metal guitars, hotly distorted synths, industrial/noise vocals, or anything else that you really want to push.

Take Home the Tube

Tube saturation has been a beloved sound used by producers, engineers, and musicians since the beginning of recorded music. Though the glory days of the vacuum tube may be over, it’s unique qualities have been reborn in the digital era.

Warm is available as both a stand-alone plug-in or as part of the Auto-Tune Unlimited subscription bundle. With Auto-Tune Unlimited, you’ll get Warm, as well as every current version of Auto-Tune. Plus, you’ll get an entire toolkit of professional-grade plug-ins (including everything from mic modelers to harmonizers and more), free software updates, and brand-new effects as they’re released. For only $24.99 a month, you can upgrade your entire vocal production workflow.


Auto-Tune Unlimited comes complete with Warm, every current version of Auto-Tune, and the entire collection of AVOX plug-ins.