Audio Editing Guide: How to Edit Audio for a Polished Sound

After the recording stage of audio production, achieving high-quality sound in your music, podcasts, films, and other projects starts with effective audio editing. In this guide, you'll discover essential techniques, tips, and tools that will help you edit and polish your sounds to prepare them for audio mixing. Using the powerful features available in Pro Tools, we’ll demonstrate how to streamline your editing process for impressive results. Let’s get started!

What Is Audio Editing?

Audio editing is the process of manipulating and rearranging audio files to achieve a desired outcome. It involves tasks such as cutting, trimming, and splicing audio clips, as well as adjusting volume levels, applying effects, and removing unwanted sounds. The goal of audio editing is to create a polished, cohesive final product that meets the specific requirements of a project, whether it's for music, podcasts, film, or other audio-visual media. Cleaning up audio during this stage is crucial because any unwanted noise or imperfections left unaddressed can be amplified during the mixing process, making these problems more noticeable and detracting from the overall quality of the final product.

How to edit audio

While each audio project carries its unique challenges, certain fundamental techniques and tasks consistently appear across different editing workflows. In this section, we'll explore these essential steps using Pro Tools to efficiently refine your audio clips, ensuring they're polished and ready for the next stages of production.

1. Start a new session

Begin by launching your digital audio workstation (DAW) and creating a new project or session. In Pro Tools, you’ll see two main views for working with your audio tracks, including the mixer window—a virtual representation of a physical mixing console—and the arrangement window, which is your primary workspace for editing and arranging audio clips.

The arrangement window is the central area where you'll manage and manipulate your recorded audio. It provides a visual representation of your audio tracks, allowing you to arrange, edit, and apply various enhancements to your audio clips with precision.

Pro Tip: Use the shortcut Cmd+= (Mac) or Ctrl+= (Windows) to toggle between the mixer view and the arrangement view in Pro Tools.

2. Import your audio and video files

With your project or session set up, the next step is to import the audio files you want to edit. In Pro Tools, you can easily do this by dragging and dropping audio files directly onto the timeline. Alternatively, you can use the Import Audio dialog by navigating to File > Import > Audio or using the shortcut Cmd+Shift+I (Mac) or Ctrl+Shift+I (Windows).

If your project involves film or video, Pro Tools also allows you to import video files, ensuring high-quality playback and editing. To import a video, go to File > Import > Video and select your video file. Pro Tools supports up to 4K video resolution, making it an excellent choice for syncing audio with high-definition visuals.

3. Remove unwanted audio and empty space

Audio editing often begins with the process of cutting and trimming audio clips to remove unwanted sections or segments from an audio recording. This can eliminate mistakes, pauses, or any portions that do not contribute to the final audio product.

Pro Tip: In Pro Tools, take advantage of the Smart Tool, which combines multiple editing functions into a single, context-sensitive tool. This tool changes functionality based on where you position it on an audio clip, streamlining the process of selecting and editing unwanted sections without needing to remember keyboard shortcuts or manually switching between different tools.

Follow these steps to remove unwanted audio from your session:

Identify unnecessary audio

Begin by carefully listening to your audio track and pinpointing the sections that need removal. This may involve identifying pauses, coughs, verbal stumbles, or other undesirable elements.

Trim unwanted audio

Trimming involves shortening an audio clip by removing unwanted audio from the beginning or end of a clip. In Pro Tools, use the Smart Tool to trim the ends of the clip. Position the Smart Tool at either end of the clip to activate the trimmer function and drag to the desired length.

Cut audio clips

Cutting is used to remove audio from within the clip. Use the Selector Tool for quick selection and cutting. Position the Selector Tool over the section you want to cut, make your selection, and then use the cut command: Edit > Cut or the shortcut Cmd+X (Mac) or Ctrl+X (Windows) to remove it.

Pro Tip: Pro Tools offers the Strip Silence feature, which is a powerful alternative to manually cutting files. It automatically detects and removes silent sections within an audio track, streamlining the editing process. To use Strip Silence in Pro Tools, go to Edit > Strip Silence or use the shortcut Cmd+U (Mac) or Ctrl+U (Windows). You’ll be presented with options to adjust the threshold settings to define what is considered "silence." Click Strip to automatically cut and remove the silent sections.

Arrange and sequence audio clips

Arranging and sequencing audio clips involves moving them around in the timeline to determine when they play. This task is fundamental for audio editing, allowing you to create cohesive and well-structured sound composition. In music production, for example, you’ll drag audio around to shape the structure of songs—like the placement of verses and choruses. In podcasting, arranging enhances the flow by strategically moving dialogue, while in sound design, it involves layering individual clips to build complex sound effects for film and video games.

Pro Tip: When working in Pro Tools' track view, you can effortlessly arrange audio clips to your liking. To do so, position the Smart Tool in the bottom half of a clip to activate the grabber tool, allowing you to freely move the clip within the timeline. For more precise control over clip placement and timing adjustments, utilize Pro Tools' Grid and Slip modes:

• Grid Mode: Use Grid mode when you need clips to align perfectly with the grid lines, which is particularly useful for maintaining a strict timing structure with music composed to a metronome. It ensures that clips snap to the grid, making it easier to achieve rhythmic precision.
• Slip Mode: On the other hand, Slip mode allows you to move clips freely between grid lines, enabling more fluid and unrestricted adjustments. This mode is ideal for making subtle timing changes and fine-tuning the placement of audio clips.

5. Create smooth transitions with volume fades

After trimming and cutting audio clips, it's essential to ensure that transitions between clips are seamless to avoid unwanted pops and clicks in your audio. For this, you can use crossfades, fade-ins, and fade-outs to facilitate smooth transitions and enhance the overall listening experience. Follow this workflow:

Listen for abrupt changes

Play your edited audio from the beginning and listen for pops, clicks or abrupt changes in volume or pacing that typically occur at points where you made cuts or deletions.

Crossfading

Use crossfades to create smooth transitions between two audio clips or segments. It involves gradually decreasing the volume of one audio source while simultaneously increasing the volume of another. Crossfading is commonly used to avoid abrupt cuts between clips, ensuring a seamless and natural flow of sound.

Fade-Ins and Fade-Outs

Fade-ins and fade-outs are specific types of transitions that occur at the beginning and end of an audio clip. A fade-in gradually increases the volume from silence to the desired level, while a fade-out gradually decreases the volume to silence. These techniques are commonly used to soften the impact of audio entrances and exits, and removing clicks and pops caused by cutting an audio clip, creating a more pleasing and natural introduction or conclusion to a piece of audio.

Pro Tip: With the Smart Tool enabled in Pro Tools, position the tool in the top right or top left corner of a clip to create a fade in or fade out. If you have two clips next to each other, place the cursor between them at the bottom to create a cross fade.

6. Create markers for quick navigation

As your audio sessions grow in complexity with multiple tracks and varied content, maintaining organization becomes crucial for efficient navigation. Using markers is an invaluable strategy for moving seamlessly across different sections of your project. In music production, these markers might organize sections of your sessions like "Verse 1," "Chorus 1," or "Bridge." For film audio, markers can be particularly useful for splitting the session by scene numbers or specific takes, allowing for quick adjustments and reviews.

Additionally, you can enhance your markers with comments, lyrics, editing notes, or mixing instructions to keep track of project details and ensure nothing is overlooked during your audio editing projects. By strategically placing markers, you can organize your workspace effectively and use keyboard shortcuts to quickly navigate between different parts of your project during the editing process.

7. Set levels and control dynamics

Another important aspect of audio editing is volume balancing and dynamic control. Whether you’re setting levels for a music mix or for the layers of a complex sound, the goal of this is to ensure your audio levels are consistent and cohesive—ensuring that every element is properly heard and that there aren’t any sudden peaks or drops in volume that negatively affect the listening experience. Follow these steps to effectively adjust volume levels:

Balance your mix

Begin by volume balancing a static mix—setting the relationships between various elements in your mix or layers in a sound. Start with all faders at zero and gradually raise each one individually. Begin with the most crucial elements and gradually introduce supporting elements.

Identify volume variations

Once you've achieved a basic balance, pay attention to any elements that exhibit significant volume variations, leading to sudden peaks and dips. Take note of these elements that require adjustment and explore the solutions below:

• Clip Gain: This feature allows you to modify the gain (volume) of individual clips, independent of the track. To use it, highlight the audio region you want to adjust, and hold Shift+Control (Mac) or Shift+Ctrl (Windows) in Pro Tools while scrolling up or down to fine-tune the volume of the selected audio. If you find a section of an audio clip that is too loud or too quiet, Clip Gain allows you to adjust the level of that specific section.
• Compression: Audio compression works like an automated volume fader, reducing the level of your signal whenever it gets too loud. Use this to create a more consistent level on audio sources that have drastic fluctuations in volume. Apply compression to smooth out these variations, ensuring a more even and controlled dynamic range.

8. Edit and correct pitch problems

Out-of-tune notes in a musical performance can distract from the overall quality and musicality of your project. You may run into situations where you captured the perfect take, but one note was off-key. Instead of trying to capture the entire performance from the start, you can simply correct the pitch of individual notes in an audio recording.

Identify Pitch Issues

Begin by carefully listening to your audio recording to identify sections where the performer played a wrong note. These issues may manifest as notes that are slightly sharp or flat, resulting in dissonance within the musical composition.

Manual and automatic pitch correction

To correct pitch, use Melodyne, which comes integrated with Pro Tools via ARA2. Melodyne allows for both manual and automatic pitch correction, enabling you to fine-tune individual notes or apply broader corrections. Right-click on the track name or the clip you want to work with and select Melodyne > Edit. This will enable Melodyne on the track or clip and give you the ability to manually adjust the pitch of individual notes or apply automatic pitch correction to an entire clip or track.

9. Correct timing issues

The timing of audio can be the difference between a mediocre and outstanding audio production. During audio editing, another key responsibility is correcting these timing issues. Timing corrections are essential for aligning audio elements, whether it's music tracks, spoken words, or sound effects. This process often involves stretching, shrinking, or moving audio to achieve precise timing. Here's how to make timing corrections during the audio editing phase:

Identify timing issues

Begin by carefully listening to your audio track and identifying any timing problems. This could include misaligned beats in music, awkward pauses in speech, or synchronization issues between different audio elements. Make a note of where these issues occur in your audio.

Use grid and snap functionality

If your project is dependent on tempo, such as music, use the grid and snap functionality. This feature ensures that audio clips, regions, or edit points automatically align with grid lines when you're moving audio around in the timeline. You can adjust how it behaves based on your desired timing resolution (e.g., beats, bars, milliseconds).

Time-stretching

Time-stretching is a technique used to adjust the timing of audio without altering its pitch or audio quality. It allows audio to be stretched (lengthened) or shrunk (shortened) to fit a particular tempo or time duration while maintaining the original pitch and audio fidelity.

Pro Tip: Elastic Audio in Pro Tools is also used for time-stretching and time compression of audio material. It allows you to manipulate the timing and tempo of audio tracks while preserving pitch and audio quality. Elastic Audio includes various algorithms tailored for different types of audio, such as polyphonic (for complex audio like chords and vocals), monophonic (for single-note or monophonic instruments), and rhythmic (for percussive and rhythmic material).

Quantization

In music production, quantization is a valuable tool for aligning musical elements to a specific rhythm. You can quantize MIDI notes or audio events to the grid, ensuring that a performance is perfectly synchronized with the beat. To quantize a clip or track, select the desired clip or track, then go to Event > Event Operations > Quantize and adjust the settings as needed.

Correcting timing with Melodyne

Melodyne is not only great for pitch correction but also for correcting the timing of individual notes. With Melodyne open on a track, drag the note or section left or right to adjust its timing. Melodyne provides a visual representation of the timing, making it easy to see and correct timing issues.

10. Remove background noise from audio

Noise reduction is a vital component of audio editing, especially when dealing with recordings affected by unwanted background noise, hiss, or hum. For instance, you might find yourself dealing with background noise like traffic, air conditioning, or overlapping conversations during an interview or vocal performance in less-than-ideal recording environments. In audio production, it’s always good practice to remove or minimize unwanted noise as much as possible to avoid amplifying it during mixing and mastering. In Pro Tools, you can use a variety of methods to fix noisy audio:

EQ

EQ (Equalization) is an essential tool for removing unwanted or problematic noise and frequencies from your audio recordings. EQ filters allow you to boost or cut specific frequency ranges, helping to eliminate low-frequency hums or high-frequency hiss. High-pass filters can be used to remove low-frequency noise such as air conditioning rumble, while low-pass filters can address high-frequency issues like electrical buzzing. Additionally, using narrow Q cuts can target and reduce specific problematic frequencies, ensuring a cleaner and more balanced audio track.

RX spectral editor

The RX integration in Pro Tools via ARA2 offers a comprehensive suite of tools tailored for detailed noise reduction and audio repair. This setup includes a spectral editor and tools such as De-click, De-hum, Gain, and Spectral Repair (Attenuate and Replace), which facilitate precise editing to eliminate clicks, pops, hums, and other intrusive noises. Additionally, it enables adjustments in volume and the repair of spectral inconsistencies directly within the Pro Tools workflow—no need to switch between applications. Simply right-click on an audio clip and select RX to launch the spectral editor. With RX integrated in Pro Tools, you're equipped to produce clean, professional-grade audio that markedly elevates the quality of your productions.

Start editing audio with Pro Tools

As you've learned, audio editing is the foundation of achieving polished and professional sound in various forms of media, from music to podcasts and beyond. By understanding the essential techniques, tools, and tips discussed in this guide, you now understand the fundamentals of how to enhance audio quality, eliminate unwanted noise, fine-tune timing and pitch, and create a seamless and enjoyable listening experience. With clean audio ready to go, your project is now ready for the mixing stage of audio production.