Oscillator Explorer

With the Oscillator Explorer you can listen to and see how different wave forms is made from basic sine waves. It has an interface that will guide you visually through the math of what is happening and also shows the shape of what you are listening to. Use your keyboard to navigate around the tool or click on the control areas with your mouse to explore.

Start by choosing a waveform using left-hand Wave cartridge panel. Number keys 1-5 are also assigned to these options as are relevant buttons if you prefer to mouse-click. These are all classic synthesis waves, such as a pure sine tone or a variable pulse wave. A sine wave has single partial. A sawtooth wave has every integer harmonic. Square and triangle waves has just odd harmonics. Pulse lets you completely remodel the spectrum.

How to Use the Oscillator Explorer

You can then pick one of the waveforms and use the Fundamental dial to alter its pitch. You’ll find this slider sweeps from 55Hz all the way up to 440Hz. If there’s any sound playing you’ll hear that note change in real-time as you slide it. Turn the Monitor trim control to set the overall volume level. It’s helpful when trying out the louder sawtooth waves against the quieter sine tones without hurting your ears.

This is what it looks like on the main screen: it displays the waveform shape for two cycles. Dragging your mouse around canvas allows you to probe the amplitude and phase anywhere on the waveform. The precise level and phase angle are showed in a readout in the corner. Alternatively, if you don’t want to use the mouse then tab into the canvas area and navigate with the Left and Right arrow keys, press Space or Enter whilst focus is on the canvas to play a quick preview of what’s being displayed.

The Partial ladder appears below screen. It shows first dozen harmonics. Each bar represents one harmonic component of chosen wave. The bar’s height indicate its relative amplitude. Tap on a bar and listen to this single harmonic partial by itself. That way you can find out what parts is contributing to the sound’s characteristics. Below the ladder is the Inspector panel displaying the selected partials’ amplitude and frequency.

In the Fourier rebuild bay, you can reassemble the waveform back into its component parts. The slider labeled Sine-part depth determines which harmonics is used for synthesis. Pressing Rebuild plays the sound that is made from only these chosen sine waves. It shows how even a simple addition of tones can produce a very complex one. You can also compare the sounds of ideal wave and the finite rebuild by pressing Contrast.

If you want to hear the entire composite tone, simply push and hold on the large Hold button at the bottom of the interface. While it’s held down the tone will play. Release and there is a smooth fade out instead of a click. It’s an excellent method for hearing how all your settings sound together.

To hear the harmonics climb one after another, just click Climb the partial ladder. A waveform like Pulse activates the Pulse width slider. Sliding this left and right alters its duty cycle. At certain widths, certain harmonics drops out and the overall harmonic content is greatly altered. In the case of the 25 percent pulse width, every fourth harmonic are gone. You have a granular view into the relationship between phase and the spectrum.

The Fullscreen button at the top of the interface makes it so that the whole thing take up your screen. That way there’s more room for interacting with the controls and visualizations. Clicking on How to play shows you a little help panel that reminds you how things work if you forget. It gives you a summary of all the keyboard and mouse shortcuts to help you get around quickly.

Reduce the depth to only a handful of partials then try altering the rebuild of the Fourier series. You will hear the roughness in this new sound different than the original wave. Build it up until you can hear that it is returning to its perfect form again. Change the wave type to Square and then to Sawtooth, noticing the difference in the rate at which harmonics die out. Move the probe around canvas and observe exact points when the waveform passes through zero and peaks.

It’s intended to be a learning tool, something to explore. Play around with all of the controls, listen to what happens when you change them, and take your time. There’s no need to be an advanced theorist to have fun with it. Let your eyes and ears lead you into the sound. Begin with a basic sine wave and gradually increase its detail over time.

So now that you understand the controls, go ahead and give it a spin. Switch the wave type, adjust the frequency and listen to rebuilds. Notice that bars on screen align with the sounds you’re hearing. It’s all about the building blocks of sound. Play around, have some fun.