Review: Sine Machine by Melatonin

There are people out there who build amazing things out of simple lolly sticks. Miniature castles, geometric sculptures, towering dioramas, you name it. I don’t know why they do this, where they find the patience, or who eats all those ice lollies for them.

(Side note: I’m available, and when it’s this hot, I work for cheap. So long as there’s air con. And in this instance, perhaps a dental plan.)

EXCLUSIVE! Get 10% off Sine Machine from Melatonin with code AUDIOPLUGINGUY

I’m reminded of these craft-stick Calders and Frank Lolly-d Wrights as I experiment with Sine Machine by Melatonin.dev. Melatonin founder and developer Sudara describes Sine Machine as a “purist” additive synthesizer, meaning it produces nothing but simple sine waves – lots and lots and lots of sine waves.

Does using only sine waves reduce the complexity found in many additive synths? Are stacks of humble sines sufficient to shape sonic sculptures as grand as the craziest craft stick creations? Is there a chance, with no lolly sticks involved whatsoever, that I could still find a way to accidentally glue my fingers together?

Let’s find out. Sines ahoy.

Value Additive’d

This is the bit where I’d typically attempt to explain something unusual about the plugin under review. In this case, I’d try to tackle additive synthesis, since it’s not the most common sort of synthesis built into plugins. But there’s only so much I can do, given my arsenal of non-classical (or any) training, wildly unreliable memory, and fourteen pages of kitchen crafting analogies.

Happily for all, Sudara and Melatonin have handled the explanation themselves with a (so far) two-part comic on their site that covers the basics, including harmonics, fundamental tones, and timbre. Sine Machine operates by generating a sine wave at the fundamental frequency of each played note along with up to 511 individual sines at corresponding harmonic frequencies, each with independent pitch, volume, and modulation LFOs.

With up to five-voice unison (20 voices in total available), Sine Machine’s building blocks multiply quickly, so it doesn’t particularly need the additional effects or noise generators you might find in other additive synths. As we’ll see, though, where an effect can be achieved using only sines and LFOs, Sine Machine has probably included it. This includes (at least an approximation of) tremolo, vibrato, “additive reverb”, and “filters” applied to volume pre-oscillation, making filtering here smoother and free of pre-ringing and other common artifacts.

That’s the “purist” part of the Sine Machine description – just sine waves and LFOs here, but shedloads of both when you need them. Now let’s check out the interface.

Sines, Sines, Everywhere the Sines

Sine Machine endeavours to make additive synthesis simpler to use – but it still requires a bit of real estate to pull it off. The plugin splits functions into five main tabs listed across the centre of the interface: Volumes, Envelopes, Trem(olo), Pitch, and Voices.

(This seems a good time to mention that the Melatonin YouTube channel has a five-part walkthrough series on Sine Machine. Each video is roughly ten minutes long, with Sudara explaining the details of a specific tab. The videos are instructive, interesting, and very helpful.

We’ll carry on here with mere words, images, and terrible header puns, but I recommend checking out the videos as well.)

In each tab view, a custom visualiser displays information above the tab list, while adjustable parameters are shown below. Let’s start with the Volumes tab:

The rainbow sculpture in the bottom half of the image above represents the first 36 harmonics for each played note, with the fundamental tone at far left. Each bar is individually adjustable; the higher the bar, the higher the volume for the specified harmonic. Set maximum volume for the fundamental and zero volume for all others to produce a sine wave, or set all harmonics to maximum volume for a sawtooth.

Beneath the parade of colourful harmonics are a global Volume control and four horizontal-line icons that highlight and allow group editing of, in order, All, Odd, Even, and Octave harmonics. A dual-mode bandpass or lowpass filter can also be adjusted at bottom right.

Sudara notes a couple of things in the Volumes tab walkthrough video that are worth mentioning here. First, while “only” the first 36 harmonics are displayed, up to 511 are created and used (for notes low enough to have more usable harmonics). This was deemed a suitable compromise to give users access to the most impactful harmonic properties without overwhelming the interface.

As indicated in the info stripe at top (when the tooltip toggle at top right is active), the volumes of harmonics past the fundamental decrease progressively. For example, the screenshot above indicates the volume of the 7^th harmonic is -16.9dB, even with a full bar, as that’s the maximum volume for harmonics at that position. So adjustments further “down the line” become necessarily more subtle.

Sweet Child o’ Sine

The walkthrough also points out that adjusting these harmonics and sculpting the “fullness” of the basic output is just the first step in Sine Machine sound design. So let’s move on to the Envelopes tab:

The main Envelopes tab parameters are shown above. Most behave in familiar ways, if you’ve worked with envelopes in other synths. Attack, Decay, Sustain, and Release adjust the time to full volume, time to fall to sustain volume, the sustain volume level, and the time to fade after note release, respectively.

Somewhat more esoteric are Offset, which spreads the attack times of individual harmonics, and Hold, which in Sine Machine spreads the fade time of individual harmonics after note release. The visualization at top reflects adjustments to all parameters, spreading, shifting, and shrinking the now-horizontal colour-coded bars representing the selected harmonics from the Volumes tab.

Each envelope parameter has a detail panel as well, allowing selective adjustment of odd or even harmonics and Low To High, High To Low, Inside Out, or Outside In ordering of harmonics when applying changes. The Relative Mode toggle at bottom right supports the potential shenanigans that unusual sets of parameter values can produce by applying new adjustments to the current envelope shape, allowing users to set up wild rhythmic combinations of harmonic triggering, volume, and decay.

The final (though fiddly) trick up the Envelope tab’s sleeve is the Edit Harmonics button on the left, which opens a spreadsheet-like grid allowing manual editing of all envelope parameters and volume gain for each of the first 36 harmonics. A bit daunting, perhaps, but available if your heart is set on making specific surgical adjustments.

Sine On You Crazy Diamond

The Trem and Pitch tabs in Sine Machine share several similar parameters, as they enable similar modulations to harmonic volume and pitch, respectively. Indeed, Sudara mentions in the walkthroughs that “Trem”olo could as easily have been called “Volume Modulation” and “Pitch” (modulation) labeled “Vibrato”.

Both tabs have selectors for modulation patterns like triangle, ramp, or square and both provide controls for modulation rate, modulation depth, and a slider to dial in how the envelope should influence modulation, with positive or inverted effect. Both the Trem and Pitch sections can be toggled on or off with a power button and the visualisations are tailored to illustrate the nature and depth of the current effect.

There’s a clever interface feature shared by these tabs (and in the screenshot above), but it’s also present on the final Voices tab, so let’s jump there to wrap up the tour. Sine Machine supports up to five Unison Voices, with controls for (pitch) Spread and Stereo separation. This tab also includes a Max Harmonics slider, allowing you to dial back the higher, less configurable harmonics, if you prefer.

The snazzy interface gizmo mentioned above is a shorthand method for selecting odd, even, or octave harmonics, or for specifying peaks or notches in the harmonics set. It’s shown below by the Glide Time and Additive Verb Mix parameters; the stack of horizontal bars can be clicked to specify a harmonic subset, while the vertical stack (which turns familiarly rainbowed when hovered over) can be pulled up or down to define notches or peaks. Those can then be dragged back and forth across the set. It’s a clever, handy, and visually consistent way to make fairly complex adjustments quite simply.

The “reverb” options here deserve a special mention, as Sine Machine’s is not a typical algorithmic reverb; like nearly everything else in this plugin, it’s made of sines. Specifically, five hundred sine waves for the left channel and another five hundred for the right behave like resonators for the input signal, reacting to the harmonics (or subsets of harmonics) passed through.

I Walk the Sine

Sine Machine absolutely succeeds at what Melatonin intended, which is to make configuring and sculpting sound in an additive synth straightforward without compromising quality, capability, or creativity. Everything from the scaled-back set of harmonics to the consistent rainbow colour-coding and illustrative visuals is designed to get you quickly elbows-deep into practical sound design without falling in completely and getting lost.

Five tabs may sound complex, but splitting parameters by concept (and keeping the number of controls fairly small) actually helps make Sine Machine more intuitive to use. It’s still possible to dig amongst the weeds – have at the Edit Harmonics pseudo-spreadsheet, if you dare – but it’s not mandatory. Nor do you need to stare down dozens of sliders and knobs (or any knobs, for that matter) among hundreds of tiny harmonic slivers. Acclimate to a couple of visual cues and clever interactive controls, and designing sounds with Sine Machine becomes smooth and intuitive in no time.

What can you design, you ask? With this lorryload of sine waves, the sky – or rainbow — is the limit. Just check out the included presets, which range from “Basic Shapes” like square and sawtooth waves to “Slow” dreamy pads, “Rhythmic” pulses and arps, “Bells and Metals”, “Bass”, “Pluck”, “Leads”, “Percussion”, and trippy “FX” of all sorts. It takes a bit of practice and experimentation, but rolling your own menagerie of unique sounds is possible and Sine Machine deftly eases the job of getting there.

Overall, Sine Machine is a fun, flexible, and approachable additive synth, all the more impressive for its “purist” approach and incredible number of sines and LFOs crammed inside. Don’t be fooled by its technicolour design aesthetic or pledge for (relative) simplicity; Sine Machine has serious chops, a wide range of capabilities, and you won’t have to read up or squint for days at an impossibly packed interface to take advantage of it.

You also won’t have to eat twelve thousand ice lollies to get at all those sine waves. Unless you want to, of course. It’s a scorcher out there.

EXCLUSIVE! Get 10% off Sine Machine from Melatonin with code AUDIOPLUGINGUY

Learn more about Sine Machine at Melatonin.dev.