24.3. Preparing Your Own Audio
Recording and producing your own audio requires a significant investment in hardware, software, and time spent learning. If you need to put professional-quality audio on your site but aren't likely to make the investment in time and equipment yourself, consider outsourcing the work to professionals.
The final product may be anything from a simple personal greeting to a live concert broadcast. The preparation of original audio requires a number of standard steps: recording, basic sound editing, then optimization for web delivery.
The first step is to make a recording of the music, spoken word, or sound effects for your site. As for most things, when it comes to sound quality, you get what you pay for. It is possible to capture sound using available resources (like the microphone that came with your computer), but the quality will not be appropriate for a professional site. The cost of recording equipment escalates quickly for each level of sound quality. An investment of $800 to $4000 in equipment (not counting the computer) is enough to get started on creating a home (or small business) studio. Getting a studio up and running also requires investments of time, effort, and education.
Although this may be a good choice for a business, it may be too expensive for many hobbyists and garage bands. It may be more cost-effective for an individual or organization on a strict budget or tight deadline to hire the services of a professional studio. Depending on how well the studio is equipped, it can cost from $30 to $250 per hour, and up.
24.3.2. Basic Sound Editing and Effects
Once you've recorded raw audio, the next step is to clean up the recording. This can involve removing unwanted sounds, setting the beginning and end of the file, and/or making a loop. You may want to apply digital effects to the sound, such as reverb or a delay.
Consider also using mastering processing techniques such as normalization or compression that can balance out the level of your audio such that no part is too loud or too quiet.
There is a huge selection of software for audio editing and format conversion. The software ranges from single-purpose utilities available via free download to professional digital-audio editing suites costing thousands of dollars. Some popular professional-level tools are listed in the following sections.
18.104.22.168. Windows audio tools
22.214.171.124. Mac audio tools
These tools can be used on Mac systems:
126.96.36.199. Tools for both Mac and Windows systems
These tools are available for both Windows and Mac systems:
24.3.3. Optimizing for the Web
After the sound files have been recorded and edited, it is time to convert them to their target web audio format and make them as small as possible for web delivery. The tool you use may depend on the file format. For instance, RealAudio and LiquidAudio have their own creation tools. There are also several tools specialized for the creation of MP3s. Tools are discussed with their respective file formats later in this chapter.
One great all-purpose tool is Cleaner 5, from Terran Interactive available for the Mac and Windows systems. This program is designed to get the best quality files at the smallest size in whatever format you choose. Cleaner can compress a number of file formats, including Quicktime and RealMedia. It can also do batch processing. The program sells for $599 as of this writing. (Cleaner is the newer and renamed version of MediaCleanerPro.)
Regardless of the tool you use, there are standard ways to reduce the size of an audio file so it is appropriate for downloading via a web page. Not surprisingly, this usually requires sacrificing quality. The aspects of the audio file you can control are:
Using these guidelines, if we start with a one-minute music sample at CD quality (10 MB) and change it to a mono, 8-bit, 22 Khz WAV file, its size is reduced to 1.25 MB, which is much more reasonable for downloading. Using MP3 compression, we can keep the quality of that one-minute sample at 16-bit, 44.1 kHz stereo (similar to CD quality) with a resulting file size of under 1MB. Combining these methods (a mono, 8-bit, 22Khz MP3), you can offer one minute clips at acceptable audio quality at only a few hundred K.
Obviously, just how stingy you can be with your settings while retaining acceptable quality depends on the individual audio file. You should certainly do some testing to see how small you can make the file without sacrificing essential audio detail.
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