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Synth Motion - A sound effects generator and synthesizer app for your iPhone and iPad!

Synth Motion is a powerful sound effects generator and synthesizer app, inspired by the famous SN76477 integrated circuit from the 1970s, but containing many enhancements.

Synth Motion is a programmable sound effects generator, inspired by the famous SN76477 integrated circuit chip from the 1970s.

It contains two adjustable frequency oscillators, the main oscillator and the low frequency oscillator (LFO). You can set the center frequency and type of each. The low frequency oscillator can modulate the frequency of the main oscillator. The frequency of each oscillator, as well as the modulation level, is controlled by adjusting the tilt of your device as you hold it in your hand. These three values are displayed at the bottom of the screen, so you can see the effect of rotation.

There is a set of buttons to select the waveform type for each oscillator: sine, triangle, sawtooth, or square. Sliders set the center frequency for each, as well as the nominal modulation level.

If you tap the color button, the controls disappear, and the screen color changes as you rotate the device, with the red, green, and blue components of the color controlled by the rotation. You can tap the screen three times to exit this mode.

Here's how modulation works. There are two audio waveforms shown below. The top one is the VCO signal, the bottom one is the modulating signal (LFO). You can see how the VCO frequency varies, depending on the amplitude of the modulating signal:

And here is another example, but this time the modulating signal is a square wave, rather than a sine wave:

Please feel free to contact us at with any suggestions you may have for the app!

Visit the Synth Motion App page page for details on how to get the app.

Are you looking for a technology or radio related iPhone/iPad app but can't find one that does what you want? Have an idea for an app that you'd like to see? Contact us at!

Email your comments and questions to

Last modified October 13, 2014