Spectral editing and repair is a process of editing audio based on its frequency spectrum, rather than its waveform. A frequency spectrum is a visual representation of the amplitude and phase of the different frequencies that make up a sound. By using a spectral editor, you can select and modify specific frequency regions or bands, and apply various effects and processes to them. You can also use a spectral repair tool to identify and remove unwanted noises and artifacts from your audio, such as clicks, pops, hums, hisses, and distortions. Spectral editing and repair can be done in real time or offline, depending on your software and preferences.
Spectral editing and repair can be useful for mastering audio for several reasons. First, it can help you achieve a more balanced and transparent sound by adjusting the frequency balance and dynamics of your audio. For example, you can use spectral editing to reduce or enhance certain frequency ranges, such as the low end, the midrange, or the high end, to improve the overall tonal balance of your audio. You can also use spectral editing to control the dynamics of specific frequency bands, such as compressing or expanding them, to create more consistency and clarity in your sound. Second, spectral editing and repair can help you fix common problems and issues that may affect the quality and integrity of your audio. For example, you can use spectral repair to remove unwanted noises and artifacts from your audio, such as clicks, pops, hums, hisses, and distortions, that may be caused by recording errors, equipment issues, or environmental factors. By removing these noises and artifacts, you can improve the signal-to-noise ratio and the fidelity of your audio.
To use spectral editing and repair tools, you need an audio mastering software such as iZotope RX, Adobe Audition, Steinberg SpectraLayers, or Magix Sound Forge. These programs may have different interfaces and workflows, but the basic steps are similar. Generally, you should load your audio file into the software and open the spectral editor to view the frequency spectrum. Then use the selection tools to select the frequency region or band that you want to edit or repair. After that, apply the desired effect or process to the selected frequency region or band. You can also use a spectral repair tool to identify and remove unwanted noises and artifacts from your audio. Finally, save your edited or repaired audio file as a new file or overwrite the original file.
I am a professional voice actor and I use the Adobe Audition spectral editing/repair features all day every day! I particularly love the "brush" tool that allows me to edit those annoying little mouth clicks and random noises with extreme ease. You can visually see those noises in the spectral display. To remove them, simply select the brush tool and drag the circle over over the "artifact" and...voila! The noise is removed. You can adjust the size of the circle if you want to get more precise and not remove too much. It's a wonderful tool!
Spectral editing and repair can be a powerful and effective technique for mastering audio, but it also requires some skill and caution. As such, it's important to use spectral editing and repair sparingly and selectively. Focus on the specific frequency regions or bands that need adjustment or correction, while leaving the rest of the audio untouched. This will help you preserve the naturalness and integrity of your sound, and avoid introducing unwanted artifacts or side effects. Furthermore, spectral editing and repair should be used as a last resort; before resorting to this technique, try to fix your audio issues at the source or with other tools. When using spectral editing and repair, always monitor your audio before and after applying any effect or process, use your ears and eyes to judge the quality and impact of your changes, use the undo/redo/bypass/preview/history functions to track your progress, and listen to your audio in relation to other tracks or elements in your project or mix. Additionally, always listen to your audio in different speakers or headphones, in different environments or situations, and in comparison to other similar or professional audio files in your genre or style.
Spectral editing techniques enhance the clarity and stability of my mixes, particularly in terms of mono compatibility. By utilizing spectral editing with EQ, i can precisely shape the frequency response of each instrument, carving out space for the vocals. This ensures the vocals remain intelligible and prominent, even when played back in mono. Controlling the bass/kick area (40 - 90 hz) in mono helps my mix to be more punchy. Furthermore, reducing low-end buildup on the sides is essential for achieving a tight and phase-aligned mix. This effectively attenuate the low frequencies in the stereo field, minimizing phase cancellation and approach results in a focused and impactful mix, free from muddiness and phase-related issues.
Spectral editing and repair can be used for mastering audio in a variety of scenarios. For example, if your audio has a loud click or pop in the middle of a vocal phrase, you can use the de-click tool to remove it from the frequency spectrum. Similarly, if your audio has a low-frequency hum caused by a faulty cable or power supply, you can use the de-hum tool to remove it from the frequency spectrum. Additionally, if your audio has a high-frequency hiss caused by a noisy microphone or preamp, you can use the de-noise tool to remove it from the frequency spectrum. If your audio has a clipped peak caused by a sudden loud sound that exceeds the maximum level of your signal, you can use the de-clip tool to restore it from the frequency spectrum. Lastly, if your audio has a reverb tail caused by a roomy or reflective recording environment that adds unwanted ambience to your signal, you can use the de-reverb tool to reduce it from the frequency spectrum.