Correctly Applying the Low Pass Filer to Audio Samples in Soundtrack Pro

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Low Pass Filter

In audio correction, much of what has to be compensated for are problems that occurred with equipment or situation when the audio was recorded. Often times, cords were receiving interference, microphones were malfunctioning, or there was an environmental sound that caused issues. There are different filters that are used in Soundtrack Pro to try and get rid of different noises that seem to creep in. If different static hums are in your audio track you may want to employ a different type of “pass” filter. What a pass filter does is it lets a specific range of tones pass through while other frequencies are blocked out. A Low Pass Filter is one that is very commonly used in Soundtrack Pro. What this does is help you to remove a high-pitched interference, such as a static hum, from the audio track. Soundtrack Pro will then allow you to keep more of the lower tones, hopefully minimizing the interference.

Soundtrack Pro Filters

Once you have exported your clip from Final Cut Pro or opened it in to Soundtrack Pro go ahead and select the entire clip so that you can apply the Low Pass Filter to the entire thing. Go up to Process and then Effects, which is the top option. Go down to Single Band EQ and select Low Pass Filter from the available options. This will bring up Soundtrack Pro’s Low Pass Filter.

The Low Pass Filter in Soundtrack Pro gives you options to change the Frequency, Order, and Smoothing of the Low Pass Filter you are applying to your audio sample. These are all going to affect the actual amount of intensity and quality of the Low Pass Filter that you apply to your clip. The Low Pass Filter is not a universal filter but instead a focus that you must then attune to your preference. In the Low Pass Filter window you can hit the play button to hear the choices that you have made with the filter before you choose for it to be alright. Once you set the filter’s preferences and apply the filter to the clip it will take a few moments for the Low Pass Filter to be applied to your Soundtrack Pro sample. You will see this progress bar in the lower left hand panel with the Actions and Details tab. You can hit the “X” button at any point in this progress to abandon the application of the Low Pass Filter, which is common to other audio mixing programs as well.


Once the Low Pass Filter has been applied you can decide what you want to do with the clip depending on what it is used for. You can easily send it back to Final Cut Pro from Soundtrack Pro as Soundtrack Pro is part of the Final Cut Pro workflow, or you can just do a normal export if it is an independent audio/video clip.

This post is part of the series: Soundtrack Pro

Here are articles and tutorials about different functions in Apple’s Soundtrack Pro, which is part of the Final Cut Studio video editing package.

  1. Batch Export in Soundtrack Pro
  2. Basic Soundtrack Pro Keyboard Shortcuts
  3. Using a Low Pass Filter in Soundtrack Pro
  4. Guide to Compressing Voice Audio in Soundtrack Pro