Q: My heavy metal band rocks! How do I put the music up on our homepage? And which format is best - my friends all tell me different things! And what about the horrible sound quality? Is it really that bad?
Todd
A:Crunching audio for the Web may sound complicated, but with the mastery of a few key applications and a little Webmonkey know-how, you can have your music online and sounding great.
The first step is to outfit yourself. Make sure you have plenty of disk space available, because audio files can be very large. You'll need an AV (audio/video) Macintosh or a Windows box with a sound card, at least 8Mbytes of RAM (it's cheap these days, so the more the better), and a sound-editing application.
Shareware, like Cool Edit for
Windows or Sound Effects for Macintosh, will do the trick
for simpler projects. But for serious functionality, you'll want a professional
software package like Pro Tools by
Digidesign. A good in-between application in terms of both price and features is Sound Edit 16 by Macromedia, the makers of Director. SoundEdit 16 2.0 doesn't
support real-time, digital, multitrack recording with simultaneous playback,
but Macromedia now distributes Deck II by
OSC to cover that issue. Used in conjunction, these two applications provide most of the tools you need to accomplish
all-but-studio-quality audio work. I recommend downloading shareware to
start with and then upgrading if you want more functionality.
Capturing sound
All set? The next step is to digitally capture the sound you want to post on the Web. If it's on a compact disc and you have a CD-ROM drive, you can import it or open up the file from your sound-editing application. If the sound you want is stored on vinyl, cassette, or a digital audio tape (DAT) machine, run a patch cord from the "audio out" port of your mixer, DAT machine, or stereo receiver to the "audio in" port on the back of your AV computer. If you don't have the right patch cord, you can probably purchase it at your local electronics store. It will prove to be both inexpensive and indispensable.
The sound I'll work with for this column came from an interview stored on a DAT cassette. I have access to Pro Tools, so instead of running a line into my PowerBook (which would have introduced an analog component), I did what's called a digital transfer, which preserves the sound quality. It's important to keep the sound as pure as possible in these early stages, because there's always a loss of fidelity in the final formatting (for the Web). When you save the file, pick a format that your sound editor supports, and append the proper suffix to the file name to avoid confusion. I wanted to save the file in audio international file format (AIFF), so I called it snippet.aiff.
Editing the audio file
Now I have a digital version of my audio file. Chances are, I'll need to do a little editing. Here's a graphical representation of the waveform for snippet.aiff. You can see that there is some extra stuff before and after the part of the signal that I want.
snippet.aiff
Let's take advantage of the digital medium and clean this up a little bit. You have to be careful with voice recordings, because what sounds like a pop might be part of a word. Make sure you zoom in on the waveform, and look at it while listening, to make sure that it is, in fact, extraneous data. The stuff at the beginning of my example is just noise, so I selected the leader and deleted it.
Then I scroll to the end of the selection and find more noise there. I faded this out to avoid an abrupt end. I end up with this sample:
snippet.aiff, cropped
If your sound-editing application has a Normalize function, now is the time to use it. This boosts the entire signal to maximum levels without distorting it. Expert functions, like Equalization, Compression, and Noise Gating should all happen at this stage as well.
Which format?
Now snippet.aiff sounds pretty clean. It's time to encode the file for access by a Web browser.
There are several companies that make encoding software. Most of them require that the decoder be in the user's plug-in folder, so it's important to pick the right one. Because there's no clear-cut standard, you should try to use the product with the widest user base and best-sounding audio. At least two applications - RealAudio and Shockwave - could fairly claim the widest user base, so let's talk about that for a minute....
In 1995, a host of audio products for the Web appeared. Internet Wave and Xing garnered early support, but it was
Progressive Networks' RealAudio that most firmly established its product. RealAudio 1.0 delivered sub-AM-quality audio that was prone to jarring breaks and distortion. The codec (compression/decompression) indiscriminatly squashed your high-quality audio, and turned it into mulch. But at least it was streaming. The sound quality improved with RealAudio 2.0, and no real competition had yet emerged. I noticed that non-techies were still decidedly unimpressed - probably because the modern ear has adjusted to compact-disc-quality audio. But Progressive's user base continued to grow nonetheless.
When Macromedia cleverly brought powerful MPEG-based technology into its Shockwave plug-in this July, it was the first substantial challenge to RealAudio. The Shockwave plug-in already had a large installed market base, and the support for high quality streaming audio made it a formidable competitor.
Because Shockwave has become something of a standard for multimedia on the Web, it's quite possible that the added functionality will make Shockwave the default audio standard for the Web. It sounds much better than RealAudio because the encoding technology is based on MPEG compression algorithms, the fruit of 20 years of psycho-acoustic research. Instead of just mashing the whole thing, these algorithms only remove the frequencies that are most likely to be redundant, resulting in a low degree of loss to the human ear. Some knowledge of Director is required to build your own player using Shockwave, but you can control what it looks like. I think that's cool.
The third major player is Netscape. Netscape 3.0 comes bundled with its own Audio Player, LiveAudio. LiveAudio automatically identifies and plays all major sound formats, including AIFF, AU, MIDI, and WAV formats. The sound quality's good, the player's programmable, and it's built into every browser. Right now LiveAudio doesn't stream, but rumor has it that Netscape 4.0 will integrate Shockwave into the new incarnation of their browser (which looks suspiciously like an OS). If this happens, Shockwave will become the default audio player, LiveAudio will probably become a Netscape utility that deals with other audio formats, and RealAudio may be shut out of the game.
Of course, if Netscape loses the browser wars, they lose the audio battle too. If you think that Netscape is doomed to marginalization, you might want to roll with the independent: RealAudio. On 17 September, Progressive released RealAudio 3.0. This version builds on Dolby technology, delivering stereo to 28.8 modems and high-quality to ISDN and LAN connections.
I encoded the sample files here with the new RealAudio encoder (not available for the Mac) only because I wanted to try it out.
Whichever format you choose, there's plenty of documentation to help you through the specifics of the final encoding process. It's important to pick the right format, but remember that you will probably end up reencoding a lot of your audio files anyway; the technology keeps improving, as we strive toward CD-quality streaming audio on the Web. The real secret to making your Web page sing is making sure your audio sounds good to begin with.
