Wavetable Synthesis: A Complete Guide +150 Free Wavetables

• Most of the major VST synths use wavetables, but what exactly are they?
• How are wavetables made?
• Download 150 FREE synthwave wavetables courtesy of Producer Hive & MGF Audio!

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Wavetable synths are dominating the market when it comes to powerful, “do-everything” VST synthesizers.

Xfer Serum, Arturia Pigments, Reveal Sound Spire, and NI’s Massive X are some of the most popular workhorse synths, all of which use wavetables. While they each incorporate many different types of synthesis, at their core are powerful wavetable oscillators capable of generating a huge range of complex, animated sounds inside a single oscillator.

It’s certainly fun and easy to play around with presets in your tracks with little regard for the technology. But it’s always useful to learn how wavetable synthesis works, and why it has come to dominate in such a huge way.

What Is Wavetable Synthesis?

Wavetable synthesis is a method of synthesis where oscillators create sound “frame-by-frame” using wavetables. Wavetables are “complex” oscillator shapes; essentially pre-defined sets of tiny wave shapes that go far beyond traditional shapes like triangle and saw waves – although these are perfectly fine, too!

(If you need to brush up on the most common synthesis methods, check out our article Wavetable vs FM vs Additive vs Subtractive Synthesis.)

Wavetable synths almost always have filters and built-in effects. Powerful synths like Serum feature a whole suite of tools to help you create custom wavetables with ease, as well as extra shaping options that are done “on the fly” to further expand the tonal possibilities.

But really, to get a good grasp on wavetable synthesis, we need to dive deeper and get to know all about wavetables.

What Are Wavetables?

Simply put, a wavetable is a 3D oscillator shape, as opposed to traditional 2D shapes like square and saw waves. Wavetables are made three-dimensional by storing many different 2D shapes in a series of frames. 

These frames are selected with a “position” parameter (WT Pos in Serum) and this changes the tone being produced by the oscillator. This parameter is often modulated by the usual sources – LFOs, envelopes, velocity, key position etc. This “animates” the oscillator, allowing you to create a huge range of morphing tones inside a single oscillator.

These frames are very small, usually 2048 samples long which is less than 50ms of audio at 44.1kHz. If you played a single frame from a wavetable just once, it would sound like a click. But inside an oscillator, this tiny sound is – of course – looped to make a tone.

Thanks to wavetables, our oscillators are no longer limited to just simple shapes or “static tones”. Inside each frame, we can have any wave we want. We can also have up to 255 other waves in the same set (at least for most synths). The possibilities really are endless.

You can also think of a wavetable as being a “frozen sound”, with no fixed duration, pitch, start, or end. You decide how quickly it plays back the frames and in what order.

A Brief History About Wavetable Synthesis

For a long time, plain shapes such as squares, saws, triangles, and sine waves built the majority of our synth sounds, and we were used to having just one shape per oscillator. We were fine with this, and still to this day plenty of useful synth sounds can be made with these simple shapes. Many great Serum patches don’t even modulate the wavetable position!

Though wavetable synths have existed since the dawn of digital synthesis, they were computationally expensive and primitive until only recently. Wavetable synthesis was pioneered by Wolfgang Palm of PPG fame in the late 1970s, and this style was adopted by Waldorf in the 80s and 90s for their Wave and Microwave synths.

Users only had limited options for creating their own wavetables, and the quality was nowhere near as good as modern VSTs like Serum. Not to imply Waldorf’s wavetable synths were rubbish – they are still highly regarded and capable of many interesting sounds. But the focus was more on processing the included wavetables with the onboard analog filters rather than browsing a library of user-generated wavetables.

Fast-forward to the modern era, where even low spec laptops can run powerful synthesizers and manipulate wavetables on the fly. Plus there’s an ever-expanding library of wavetables available on the internet (don’t forget to download the ones at the end of this article!).

(After some good free synths? Check out our list of the best free VST synths on the net!)

“Animated Oscillators”

The way wavetable oscillators work is comparable to animation. You can think of sprite sheets in 2D video games, where animated sequences are stored as a series of images in frames. These images are pretty small – often less than 100 x 100 pixels. This is similar to wavetables, which have many tiny “snapshots” of audio. So moving through a wavetable is frame-by-frame animation but with sound!

Similar to animation, the order of these frames is important. In most cases, wavetables are arranged so that as the position travels from the first to the last frame, the timbre changes naturally without any jarring moments. Your wavetable may be representing a filter sweep, but no one will know this if the frames are all over the place!

However, sometimes wavetables are presented as a library of single shapes, and aren’t intended for “animation”.

For example, a wavetable may contain basic oscillator shapes from a particular vintage synth and hence only consist of 4 frames – saw, square, sine, and triangle. Or maybe the wavetable consists of 8 different saw waves from 8 different synths. These static tones are great for reinforcing more complex sounds.

Unlike traditional animation, wavetables have the advantage of being “played back” in a number of ways: forward, backward, just a little bit at a time, even randomly. The results can be surprisingly smooth and organic, even with extreme modulation.

Wavetable Technicals

Wavetables are typically stored as WAV files just like samples. But while samples contain a single possible sound that can be any length, wavetables contain many different single cycle waveforms stacked together and are rarely longer than 12 seconds.

(Need some fresh samples? We rounded up the best websites for free sample packs!)

“Single cycle” means one single wave oscillation, so with a saw wave, once it reaches the top and starts again, that’s a single cycle. If you zoom really far in on the samples in your DAW or sampler, you will see they consist of many different single-cycle waves, which are all elegantly joined together to make the final sound.

While this is a good visual metaphor, it’s worth remembering that the frames in wavetables are all precisely the same length. Recorded sounds are made up of many overlapping cycles at different frequencies and phases, so it’s a naive comparison at a certain point.

As mentioned, there can be up to 256 “frames” per wavetable. More frames are theoretically possible, but many synths max out at 256 because that’s all you really need. Many interesting wavetables can be made with just a few frames anyway!

Wavetable synths can fill in the blanks between frames, meaning you can make do with just a few and still make slow-moving pads and sweeps.

How To Make Your Own Wavetables

This is a topic that easily warrants an entire article (keep your eyes peeled) but there are still some basic approaches that can be quickly explained.

There are numerous methods for creating your own wavetables. You may choose to make one from a recorded sound or sample, breaking it down into single cycle waves to make your wavetable. You can also algorithmically generate wavetables from the ground up with mathematical processes.

There are no popular third party programs for making your own wavetables, so your best bet is to look at the wavetable editor in your synth of choice. However, another option is WaveEdit by Synthesis Technology – it’s free, open-source, and cross-platform, but sadly has not seen an update since Feb 2018.

Serum comes equipped with a powerful wavetable editor with a wide range of tools for creating your own wavetables in a matter of seconds.

Serum can create wavetables from sound files in a number of ways. It can track the pitch of sounds to figure out where each cycle is, or it can convert sounds to a series of spectral frames and create a wavetable from these instead. Importing sounds this way can be hit or miss and it’s best to use sounds that have been created specifically with wavetables in mind. (The Serum manual suggests some ideal specifications for this approach).

Serum also includes additive features, letting you create wavetables by setting individual harmonic and phase levels for each frame. A total of 512 harmonics are possible, which is a truly absurd amount of detail. An obvious downside to this approach is it can be very time consuming setting up wavetables this way. However, there are some processes available to speed things up, which are accessed by right-clicking on this view.

Also included in Serum’s wavetable editor is a truly powerful formula parser for creating wavetables with mathematical functions. This is the quickest way to generate a whole set and you don’t have to be a math genius to play around with it. You can take the preset formulas and tweak the numbers to get different results. Before long, you’ll figure out how to write your own formulas. Once again, consulting the Serum manual will help a great deal with this.

A hidden feature of Serum is its ability to make wavetables from image files. Simply drag an image onto an oscillator and Serum translates the brightness of each pixel into individual sample values. For best results, work with PNG images that are 2048 x 256 in size. These numbers are chosen to match the samples per frame (2048) and maximum number of frames per wavetable (256). PNG is used instead of JPG because it is lossless.

Want to go a step further? Check out this video that shows you how to create your own wavetables from 3D objects made in Blender!

Producer Hive Synthwave Wavetable Pack – 150 Free Wavetables

As a bonus for our readers, we’ve prepared a whopping 150 free wavetables courtesy of MGF Audio.

Though they are designed with synthwave in mind, they can work in any genre, and are just as suitable for house and techno. There’s a healthy selection of wavetables taken from vintage analog synths and digital classics like the Yamaha DX11.

Also included are 50 wavetables taken from Producer Hive’s Analog and Vintage Wavetable Packs, which have over 400 wavetables from various hardware units.

In this pack you’ll find 158MB of content, with wavetables suitable for fat basses, pads, leads, and stabs. There is an emphasis on clear and bright lead sounds that can be used at the very front of your mix.

These wavetables work in Serum, Ableton Wavetable, and many other popular wavetable synthesizers. Just consult your synth’s manual for instructions on importing custom wavetables.

Inside you’ll find:

• 70 analog wavetables.
• 31 digital wavetables.
• 49 additional analog wavetables from MGF’s AnaWaves pack.
• Instructions for using wavetables with Serum and Ableton Wavetable.

If you like them, make sure you share them around! They’re royalty-free, so you’re welcome to use them in your own professional synth patches.

Download them here.