Do you want to know how I get myself in trouble with my wallet? It’s easy. First, I discover an app that takes a different approach to something I’ve never known before, then I seek out its hardware equivalent( if there is one ), and then I buy it, along with the app. The good news is, most of the time, I don’t have the funding to purchase said hardware, but when I do….

This happened when I had written about FM4, the Frequency Modulation synth app. I ended up purchasing a Yamaha DX27 on eBay, and ultimately buying a Korg Volca FM. Well, here I am, reviewing another app and scouring eBay for it’s hardware sibling. Submitted for your edutainment, I give you Phase 84.

Phase 84 by Retronyms is a phase distortion synthesizer app that was influenced by Casio’s CZ series synthesizers in the 80’s. Phase distortion synthesis is similar to Frequency Modulation Synthesis(technically, it’s Phase Modulation) in that it performs a similar function, using a digital waveform to manipulate another waveform, thereby changing the harmonic structure of the output. There are differences in the two types of synthesis. Here is an excerpt from Wikipedia on how harmonic content is generated through phase distortion:

Casio’s implementation of PD used oscillators generated by modulator and carrier waveforms, synchronised to each other per-cycle. The modulators were various angular waves that could ‘distort’ the carrier’s sine into other shapes, to a degree derived from the “DCW” envelope. In doing so, many harmonics were created in the output. As modulators were rich in harmonic content, they could create spectra more linear, i.e. more similar to traditional subtractive spectra, than Yamaha’s phase modulation (PM/FM) synthesis. PM does not require oscillator sync but was for a long time limited to sine waves, which meant output spectra bore the non-linear hallmark of Bessel functions. PD is a different type of PM – whose very different modulators caused significant difference in operation and sound between PD and PM. Thus the two aren’t directly equivalent.

The phase transforms are all assembled from piecewise linear functions under binary logic control and shows characteristic sharp knees (and for some transforms, even sudden jumps) as they move from minimum to maximum, where the frequency counter’s accumulator wraps around and starts over. The sharp knees are smoothened out by the roundness of the modulated sine wave and not too noticeable in the resulting signal.

There’s more, but that’s the gist of it.

It’s been stated that this form of synthesis, while digital, actually sounds warmer than FM synthesis. Knowing this, I looked into Phase 84 and ran it through it’s paces. Because most of what’s going on here, in terms of layout, is foreign to me, I started with playing with the controls and seeing what happens. I was able to coax some interesting tones and timbres out of it, from bell-like FM sounds to fuzzy sawtooth waves of ambient noise. The filtering section seemed a little confusing to me, as Phase 84 uses a shaper to create a filtering effect. Once I figured out how to use it, I was able to do similar sounds as I would in analog synthesis. The feature by which I’m most impressed is the delay section. you would think that a synth app would focus most of its processing on the synth engine and either eschew effects altogether or just throw a mediocre echo effect on there and call it a day, but the Phase 84’s delay is by far, my favorite. Phase 84’s delay appears to replicate a vintage tape echo. The loss knob simulates the fade that one would get when the tape starts to degrade over time. I pulled my favorite trick out of my bag and cranked the feedback control to max, then turned up the loss knob to the point of the repeats fading to a dim haze, leaving just enough sound to create a sonic bed in which the synth tone can rest. Brilliant!

Here is Retronyms’ App Store description:

Phase84 is a next generation phase distortion synthesizer. It fuses gritty digital sounds with traditional analog punch.

Phase84 is a Tabletop Ready App. Combine Phase84 with drum machines, sequencers, effects, and more inside Tabletop — a free modular music app for iPad.

Phase84 is an extremely capable synthesizer and features over 110 presets, containing all sorts of basses, leads, pads, bell tones, sweeps, atmospheric sounds, pseudo-realistic tones, and more. While you don’t need to know much about synthesizers to get a lot out of Phase84, experienced synth tweakers will be thrilled at the sheer variety of unique sounds that can be produced with this incredibly versatile synth.

So What’s Phase84 All About?

Phase84 is what’s known as a Phase Distortion synthesizer. This form of waveshaping synthesis has its roots in Casio’s brilliant CZ line of digital synthesizers from the 80s. It is designed to have the warmth of a subtractive (analog) synthesizer, yet be capable of the squelchy tones and sharp attacks of an FM synth. Phase84 in particular can create warm pads, glitchy sounds, dirty basses, filthy sweeps, screaming leads, and anything in-between.

For those familiar with the typical Moog-like (or iMini-like!) synthesis, think of the “shaper” as being synonymous with “brightness” or “filter cutoff”.

More than 100 presets.
MIDI support.
inter-App Audio support.
Advanced Keyboard section.
Expressive Perform Mode with Groove Gate.
Tabletop Ready App.
Precision Knob mode.
Phat, naturalistic unison feature for super thick pads and sweeps.
Oscillator Section: 9 Params, 2 General-Purpose Oscillators, 1 Formant Oscillator.
Mix Section: 8 Params including Delay Amount and Pulse Width.
Envelope Section: Amplitude and Shaper Envelopes. Fully visualized and interactive ADSR plus special Fade Param.
Delay/Filter Section: Stereo delay with loss modeling and a punchy overdriven analog-style filter.
3 LFOs: More flexible than your average LFO, this has 4 waveforms, optional delay and repeat count, and can go into the audible frequency range.

There’s so much more to cover here, so be looking for a demonstration video on my YouTube channel. If you are interested in buying this app, you can purchase here:

Phase 84

Thanks for reading and as always, happy apping!