SOUND FORMATS

 

                  Sound /Audio  Formats                                     

Sound frequency is the speed of  the sounds  vibration which determines the  pitch  of the sound .sound is caused by the vibrations  that is transmit throw the medium such as air and reach the ear or some other form of detecting the device.

The sound is measured as the number of wave cycles that occur in one second, with the standard unit of measurement being Hertz (Hz).

A frequency of one Hz refers to one wave cycle per second, while 20Hz refers to 20 per second, where the cycles are 20 times shorter and closer together.

Humans with normal hearing can hear sounds between 20Hz and 20,000 Hz , frequency above 20,000Hz are know as ultrasound

Best audio file format and codec

From MP3, MP4, AAC(Advanced Audio coding) and more, there are many audio file formats you can expect to come to across as a developer handling.

Ø Best audio format for sound quality:  A Lossless audio file format is the best format for sound quality. these  include FLAC,WAC or AIFF. These types of files are considered “hi-res” because they are  better or equal to CD-quality. the tradeoff is that these files will be very large.

Ø Best audio format use on the web: From a browser compatibility  standpoint , .MP3  and .MP4 are the best audio file formats for use on the web. Other formats that are supported by most browsers include OGG, Web m, AAC, and WAV.

Ø Most popular audio format: MP3 files are the most popular audio format. their ubiquity inspired an entire category of devices(MP3 Players), and their popularity continues to this day. MP3s can be created in a variety of bit rates.

The most popular audio files

1.     LOSSY FORMATS:  Lossy audio formats lose data in the transmission. They don’t decompress back to their original file size, so they end up smaller and sound waves are lost. Artists and engineers who send audio files back and forth prefer not to use lossy formats, because the files degrade every time they are exported.

·       .MP3:  These files are the most common audio file around. .mp3 files can be encoded at a constant bit rate or variable bit rate. A constant  bit rate ensure the same quality throughout the audio file but results in higher file size.

·       .AAC: these are much higher in quality than any of the audio file formats on the list, despite being a tad higher in quality. These files are open source. these are commonly associates with tunes and gaming consoles. Requiring less than 1mb per minute of music and sounding better than mp3 at the same bitrate. AAC formats used by apple music, YouTube, and android.

·       .OGG: OGG is free open video format file which is designed to provide efficient streaming and manipulation of high quality digital multimedia. The OGG file is similar to an MP3 file ,but has better sound quality then an MP3file of same size. It can include song metadata, such as artist information and track data. It supported by many media players and some portable music players.

 

2.     LOSSLESS FORMATES: these files decompress back to their original size, keeping sound quality intact . audio professionals want all of the original sound waves, so they prefer lossless. These files several times larger then mp3s.

 *FLAC(Free lossless audio codec):it is an audio coding format for lossless   compression of digital audio, developed by the xiph.org foundation. this is similar to zip works, except with FLAC you will get much better compression because it is designed specifically for audio 

 *ALAC(apples  lossless audio code):it allows for lossless compression, but it works only on Apple device. 

*M4A: it is an apple-based format that corresponds to .mpeg-4 video files. M4A  files lossless compression, allowing for a multiple edits without a loss of quality . this files play audio on Apple products such as i phones and i pod

3.     Uncompressed formats:

·      WAV (waveform audio file): retains all the original data, which makes it the ideal format for sound engineers. ”WAV  has greater dynamic range and greater bit depth”, creative producer format.it is the highest quality, it can be 24-bit,32-bit, all the way up to 192KHz sample rate and even higher these days. this  can be especially useful for video projects in which exact synchronization is important.

·      AIFF(audio interchange file format): Originally created by Apple, these  files are like WAV files in that they retain all of the original sound and take up more space than M3s. these  can play on macs and PCs, but they don’t hold time codes, so they are not as useful for editing and mixing.

·      DSD: direct stream digital is an uncompressed, high resolution audio format. These files encode sound using pulse-density modulation. Hey are very large, with sample rate as much as 64 times that of a regular audio CD, so they require top-of-the-line audio system.

·      PCM  :  pulse-code  modulation, used for CDs and DVDs, captures analogue waveforms and turns them into digital bits. Until DSD, this was thought to be the closest you could get to capturing complete analogue audio quality.