100 Things #34: Display Phase Measurement Alongside Frequency Response

Its simple to display phase measurement alongside frequency response when making audio measurements in SoundCheck. Watch this short video to learn more.

Displaying Phase Information in SoundCheck

More Resources about Phase Measurement

The best resource for learning how to use SoundCheck is the SoundCheck User Manual

Check out our knowledgebase articles on displaying the phase of a curve and displaying unwrapped phase.


Video Script: Display Phase Information Alongside Frequency Response

Today, I’m going to show you yet another useful feature SoundCheck offers that many people are unaware of. We often talk about measuring the frequency response of a loudspeaker. This is probably the most commonly used metric to objectively display how a speaker sounds when playing back music. When we measure the frequency response, what we are essentially doing is a 2 channel FFT transfer function, transforming waveforms in the time domain into the frequency domain. A natural by-product of a transfer function is the Phase response. While the frequency response magnitude gives you the amplitude of the frequency components relative to others. The phase response describes how the frequency components align in time, and is critical in determining the transient response of a loudspeaker.

Since Frequency and Phase response go hand in hand, SoundCheck automatically calculates both of these in Analysis although phase is not displayed by default. Phase is stored as a Z value for every X and Y value where X and Y are the Frequency and amplitude. You can display the Phase response alongside the frequency response on a graph by simply right clicking on the graph and check-marking Phase.

SoundCheck also comes with an Unwrap Phase function that can be applied to any Phase response measurement to remove any discontinuities in the response due to the phase exceeding +/- 180 degrees and make it easily readable by adding or subtracting multiples of 2 pi as appropriate. Once again, this can be toggled on or off in the right click menu.

One of the beauties of SoundCheck is that for any post processing operations on the frequency response that have direct effect on the phase response, SoundCheck automatically makes sure that the Phase is adjusted accordingly. For example, if you invert a frequency response, SoundCheck defaults to inverting the Phase response too, still offering you the flexibility if you choose not to.