AAC vs AC3: What's the Difference and Which One to Choose?

AAC: Short for Advanced Audio Coding, AAC is an audio coding standard for lossy digital audio compression, a successor to MP3 but outshines MP3 in its performance(The higher compression efficiency gives AAC a better sound quality than MP3 at the same bit rate). It has up to 48 channels, yet it is often used in two-channel mode.

AC3: Also known as Dolby Digital, AC3 is an audio compression technology that stores audio in a lossy form. It contains up to six discrete channels of sound and the most common use is associated with the 5.1 channel configuration - five channels for normal-range speakers and one channel for the extra low-frequency effects.

Also read: AAC VS FLAC | DTS VS Dolby Digital | WAV vs MP3 | OGG vs FLAC | OGG Vorbis VS MP3

The following criteria are essential in making a judgment about an audio format, so they would be necessary standards in deciding which one, AC3 or AAC, will be the best pick.

1.Sample rate

AAC: 8 to 192 kHz

AC3: 32, 44.1, 48 kHz

Tips: The higher the sample rate the greater the dynamic range, which means more detail will be captured and the quality of the audio will be better.

2.Bit rate

AAC: 8-529 kbit/s (stereo)

AC3: 32-640 kbit/s

Tips: A higher bit rate normally guarantees a better quality.

3.VBR

AAC: Yes

AC3: No

Tips: With VBR, the audio can be stored in an economic way by allocating a higher bit rate to the more vibrant parts of media files and a lower bit rate to the more constant segments. In this way, it can produce an audio file with a smaller size while preserving sound quality.

4.Quality

With same bit rate, especially in low bit rate, AAC has a better sound quality than AC3.

5.Applications

AAC: It is supported on Windows, macOS, Linux, BSD, Unix, Palm OS, Symbian OS, Rockbox, iOS, Android, Chromium and it is widely used in Digital TV service, Digital Radio, Internet streaming.

AC3: It is supported on Windows, Linux, and iOS and it is widely used in cinema, TV broadcast, radio broadcast via satellite, digital video streaming, DVDs, Blu-ray discs, and game consoles.

In terms of audio quality, AAC appears to have higher resolution than AC3. But AC3 beats AAC in the field of surround sound since AC3 is widely used for home theaters to provide immersive 5.1 sound effect. It is up to you to decide whether AC3 or AAC is to choose according to your demands. But one thing to note is that many software or players do not support AC3 format and you may need to convert AC3 to AAC if an audio codec issue occurs.

When playing video with AC3 or AAC audio, you might come across issues like AAC not playing in your home theater or AC3 not supported on your Android player. Converting AAC to AC3 and vice versa can get this kind of problem handily solved. The tutorial below shows how to convert AAC to AC3 in a video with a versatile video converter WonderFox HD Video Converter Factory Pro.

Before start, please free download the software and install it on your PC.

Step 1. Run the software and open the Converter. Next, click +Add Files on the top left corner or directly drag and drop the source file into the program.

Step 2. Click the format icon on the right side and a list of video/audio formats and preset specs would appear. Go to the Video category and select the same video format as the output profile.

Step 3. Open the Parameter settings below. Go to the Audio settings and change the audio encoder to your desired format, such as AAC. Then click OK to save the changes.

Step 4. Finally, hit Run to start the conversion.

Tips. The software also allows you to extract audio from video and change audio bitrate.