User Manual
Table Of Contents
- 1: INTRODUCTION
- Intended Audience for this Guide
- About the 2014 Edition
- Additional Resources
- About iZotope
- 2: WHAT IS AUDIO REPAIR AND RESTORATION?
- 3: AUDIO REPAIR AND RESTORATION BASICS
- 4: Understanding Spectrograms / Identifying Audio Problems
- 5: WHAT IS RX 4?
- 6: DENOISING
- 7: TIPS AND TRICKS FOR EDITING DIALOGUE
- 8: BROADBAND NOISE REDUCTION
- 9: REMOVING INTERMITTENT NOISES AND GAPS
- 10: REMOVING CLICKS AND POPS
- 11: REMOVING CLIPPING
- 12: REMOVING REVERB
- 13: EXPORTING AND DELIVERING AUDIO
- Exporting and Delivering Audio in RX 4
- 14: SUMMARY
- 15: ABOUT THE AUTHORS
- APPENDIX A: GETTING SET UP TO REPAIR AND RESTORE AUDIO
- APPENDIX B: GENERAL RX 4 TOOLS
- Appendix C: REPAIRING THE INCLUDED AUDIO FILES
- Example 1: Removing Broadband Noise from a Concert Recording
- Example 2: Restoring an Historical Speech: Making Voice More Intelligible
- Example 3: Cleaning up a Phone Interview with Declick and Spectral Repair
- Example 4: Removing Clicks and Pops from a Concert on Record
- Example 5: Removing Clipping from a Phone Interview
- Example 6: Removing Guitar String Squeaks with Spectral Repair
- Appendix D: Tips from the Pros
12
AUDIO REPAIR
AND ENHANCEMENT
4: UNDERSTANDING SPECTROGRAMS /
IDENTIFYING AUDIO PROBLEMS
As with medical diagnostics, the key to successful audio restoration lies in your ability to correctly analyze
the subject’s condition. This can be a life-long, never-ending quest—constantly honing the ear to distin-
guish the noises and audio events that need to be corrected.
To get started, it’s important to identify the problems with your file and identify which tool(s) will give you
the results you want. Let’s briefly look at how to examine your audio using the spectrogram and waveform
display tools, then consider how to identify audio problems using these displays.
WHAT’S THE GOAL OF USING A SPECTROGRAM?
The aim of any good visualization tool for audio repair and restoration is to provide you with more infor-
mation about an audible problem. This not only helps inform your editing decisions, but, in the case of a
spectrogram display, can provide new, exciting ways to edit audio—especially when used in tandem with a
waveform display.
RX TIP • Use this
special slider in RX 4 to
blend between detailed
spectrogram and wave-
form views.