Chapter 12 Internet Radio and Other Distribution Platforms

This chapter looks at the techniques the people should consider for creating an internet radio station, podcast, or production service, as well as several online and over-the-air radio distribution methods. It focuses on what the people need to consider in order to create audio content for online distribution. The good news is that many people have modems that operate from 1.5 to 12 Mb per second, so streaming live audio or downloading audio files is not that much of a problem. Updated encoding and playback software is often very appealing to content providers, in that it often provides better-quality sound with smaller file sizes, and allows more simultaneous outgoing streams. In fact, with just a computer, a microphone and appropriate audio editing software, the people could record productions for internet radio stations, podcasting, and other internet applications. Copyright in relation to online content and distribution has become a major concern.

12.4 Encoders

Audio Compression

Audio compression degrades quality somewhat, though much in areas that won't be missed. Through a process called ‘perceptual coding,’ soft sounds that are masked by loud sounds are removed, sounds occurring equally in the left and right channel are combined, silences are removed and so on. Click below for examples.

Original Uncompressed Recording

128Kb Compression

56Kb Compression

24Kb Compression

Reducing Sample Rate

Reducing the sampling rate can cut the file size of uncompressed audio, though the sound quality, especially with higher frequencies, can be adversely affected. Compression offers smaller files with less loss of quality, so it is a better choice for the internet than audio with a low sample rate.

CD Quality 44,100 Samples Per Second

22,050 Samples Per Second

11,0225 Samples Per Second

Reducing Bit-Depth

Reducing the bit-depth can cut the file size of uncompressed audio, though it introduces noise, so sound quality can be adversely affected. Compression offers smaller files with less loss of quality, so it is a better choice for the internet than audio with a low bit-depth.

16-Bit Recording

8-Bit Recording

Reducing Sample Rates and Bit-Depth

A combination of reducing the bit-depth and the sample rate can cut the file size of uncompressed audio, though it degrades higher frequency sounds and introduces noise. Compression offers smaller files with less loss of quality, so it is a better choice for the internet.

16-Bit

44.1K

22.05K

11.025K

8-Bit

44.1K

22.05K

11.025K

12.6 Players

Buffering

Quiz