converting aac files to mp3 using audacity

#Converting aac files to mp3 using audacity full
#Converting aac files to mp3 using audacity portable

Variable Bit Rate files are commonly used to get the best audio quality by 'saving up' bit on easily encoded sections such as silence or simple audio and then using them for difficult to encode noises such as applause, harpsichords or hi-hats. You might sometimes find MP3 audio files at 16, 32 and 48 kHz but these can cause problems with Moodle and elsewhere and so ideally should be re-encoded following the instructions given below. 44.1kHz is probably the most compatible and a good default choice but 22 and 11kHz are fairly standard too.

Due to something called the Nyquist Theorem you need twice the frequency of the sounds you wish to record. Sample rate is the number of times per second that the sound is digitally recorded. Somewhere between 32 and 96 kbps is appropriate with diminishing returns beyond 128kbps. The latter is a measure of filesize and download time and also a rough measure of quality. Note that 'sample rate' or frequency, measured in kiloHertz (kHz), is not the same as 'bit rate', measured in kilobits per second (kbps).

#Converting aac files to mp3 using audacity full

Joint-Stereo, rather than Mono or Full Stereo.Constant Bit Rate (CBR) rather than Variable Bit Rate (VBR).The short version follows, it is explained in greater depth below: Flash requires the audio to be in a fairly specific format and this happens to also ensure the widest possible compatibility in other situations e.g. The Media Filters in Moodle use Flash to playback audio in the browser. If you are creating audio files, or having them created for you we suggest some specific settings for your MP3 in the next section.

#Converting aac files to mp3 using audacity portable

It is the most widely used format and is likely to be playable on any modern computer, internet connected device or portable player. If you have a choice in the matter we would suggest choosing MP3. The following formats are widely used and if not already present on a computer, easy to use software can be easily downloaded and installed at no cost. Alternatively, you can try to ensure that the media filter doesn't attempt to process the problematic file. If this is the case then you may need to follow the Advanced Method outlined below to prepare your audio files for use within Moodle. It can however, in some rare cases cause your MP3 files to sound faster and higher pitched, making normal speech sound like Minnie Mouse, or slower and lower pitched.

Turning this on is recommended, and is a job for your Moodle administrator. Moodle has a facility called Multimedia plugins that can make the presentation of some kinds of downloaded audio and video files more streamlined.

6.1 Using Audacity to Convert audio and Record voice.