This one is a cool interactive tool called Phase Cancellation Simulator. It illustrates what happens to two sound signals as they combine. By dragging your mouse around or using the keys on your computer keyboard, you can control instrument. It also helps visualize math of subtracting one signal from another. This explains why two identical sounds cancel out completeley if they meet with opposing polarity.
The interface is divided into three sections: a control deck, a waveform display, and a vector dial. Channel A always stays pinned at zero degrees and channel B are shown as a vector relative to that (left). Dragging the vector outwards increase the amplitude while rotating it around the circle adjusts the phase angle. Below you see the separate channels as waveforms and total sum. The equation box shows math behind the signals. It shows how much each one cancel the other in decibels and final resulting amplitude.
How to Use the Simulator
You can control instrument by clicking and dragging with your mouse. You can control the instrument by clicking and dragging with your mouse or by using your computer keyboard. You can use arrow keys to move the vector dial around. Left/Right rotate the phase one degree at a time. If you hold down Shift while using those arrows, it will jump in increments of ten degrees. Up/Down control amount of channel B being added. Anywhere on the page, certain other keys will do their thing. For example: M = Listen to the sum buss. A = Only Channel A. B means only Channel B. T = Hold a tone so you can see changes as you make them. N = Phase sweep. Q = Throw a bunch of random phase faults into the mix. K = Test it out. Escape, kill everything.
Fine-tuning adjustments is made via sliders on the control deck or by using keyboard shortcuts for precise changes. The phase lag slider sets manual rotation angle, which synchronizes with corresponding delay slider. The delay slider indicates the time offset in milliseconds relative to the phase shift occurring at the reference pitch. Reference pitch slider… Adjust this slider to hear how phase cancellation act at various frequencies. Wider wave cycles at lower pitches make it easier to see the null point. Use the track level sliders for A and B. Match/mismatch the amplitudes here. If levels are equal, they will cancel each other out perfectly. Mismatches will result in sum never reaching zero. Monitor level slider, Sets overall volume going out to your speakers.
A set of two toggle buttons in the deck adjust signal characteristics. You can flip phase of channel B precisely one-hundred eighty degrees with the rotate B button. This would of let you move quickly between destructive and constructive interference. With a twist of the source buttons, you can select either a triangle wave or a sine wave. A sine wave is clean and simple. The math are easy to follow. A triangle wave adds harmonics that interact with the phase shift in more complicated ways. The combined waveform turns violet to show what resulting mix looks like.
One of their more practical drills is the fault drill section. Here, you can click scatter to create a random scenario with an incorrect phase angle and mismatched levels. Adjust the sliders until you get the cancellation at or over forty decibels. It will let you know when you’re there by showing it on the status bar. It’s a great way to develop intuition about how to identify and fix phase issues in a mixing context. Locking in your settings seals the null, then you’ll see the final depth reading.
Here are some practical tips to get more from the simulator: Always begin by setting both A and B for the same level. Phase rotation only equals a full null when amplitudes is equal. While adjusting the vector dial, use the hold tone button. It’s more intuitive to hear the sound drop out closer to the sweet spot rather than watch the lines come together. Change the phase across the null at different frequencies. What you’ll find is that width of the cancellation dip varies according to pitch. Lower frequencies cancels more gradually, while higher ones cancel abruptly. The fullscreen button expands the workspace as well, which is useful when you wish to study the vector geometry on a bigger canvas.
All conventions and controls are available in the help panel, and they remain out of sight until required so the main view always stays clean. Animations is paused if your system settings demand this, and the tool respects reduced motion preferences. To begin, turn on the hold tone and spin the vector dial. Watch the combined waveform flatten out when approaching one-hundred eighty degrees of phase. Mess with the levels to observe that not everything balance to zero. Engage the fault drill and discover if you can locate the null without looking.
The simulator makes otherwise unclear audio ideas real. It allows you to explore them in whatever order you choose and learn more about how signals interact with each other.