The Future... For Now

By Craig Jackman

You can ask them yourself. The main reason that the management of CHEZ-FM finally got a computer system was to send audio material to our sister station in Smiths Falls, Ontario (digital editing was just a nice bonus). For years we had either been sending tapes with people who were driving that way anyway, or put tapes on the bus, until D.C.I. came along. Not to knock D.C.I.—which works great—but management really got quite sick of spending over $500 a month on it. When you added in the lost tapes, and time wasted at either end going to the bus station to pickup/drop off the tapes, we needed an alternative, and thanks to music lovers on the ‘net, there was one ready made for us.

What we have chosen to do is take our material from the computer, where they are stored as .wav files, convert them to .mp3, and send them over the Internet.

A little background first. MP3 is an audio compression algorithm. MP3, a.k.a. MPEG 1 layer 3, is an open standard owned by nobody, but designed by a group of scientists called the Moving Pictures Expert Group, which operates under the direction of the International Standards Organization (ISO) and the International Electro-Technical Commission (IEC). MP3 was designed to permit listenable quality audio to stream through a POTS phone connection.

At low bit rate settings, you can stream .mp3 files in real-time through a 28.8kbs modem connection, although the term “listenable” is highly debatable. At higher bit rate settings, you can get near CD quality, but the files must be downloaded then played. The advantage is that MP3 will take a .wav file and shrink it to a manageable size to send. Remember that 60 seconds of CD quality audio takes up about 10Mb of space. Depending on the bit rate you choose, it is easy to get a file that still sounds good, but takes up only 1/10th the space. Naturally that will transfer much faster!

How much you compress the file depends on the bit rate setting. Most bit rate settings are fine for FM quality. A trained ear will be able to pick out the artifacts of the processing, but the average listener couldn’t tell the difference. Low bit rates are fine for AM, and extremely low bit rates make for an interesting effect.

What kind of settings am I talking about? The Internet standard is 128kbs, which I find to be cassette quality. 160kbs and 192kbs are fine for FM. When I’m transferring material where quality is most important, I choose 256kbs, a setting where I have to strain to find any artifacts. A 30-second stereo spot at 256kbs compresses down to about 1Mb, and takes about 5 minutes to send. On the other hand, 32kbs makes an interesting effect, but has the sound that gives computer audio a bad name.

There are two ways of sending, either via FTP transfer or as an e-mail attachment. Sending as an e-mail attachment is the easiest, though slower way. I’ve even been sending some clients their spots in MP3 as e-mail rather than doing cassette dubs. The advantage of that is that the sales rep can’t loose the tape, the quality can be better than cassette if desired, and it’s a great way to maintain some personal contact with the client. Doesn’t everyone have e-mail access these days? FTP (File Transfer Protocol) is faster, but it takes more prep work, plus a program that will transfer your material that way. You have to have either an Internet site that you will give other stations access to, to download your .mp3 files, or access to their Internet site where you upload the files. Either your station engineer or your Internet Service Provider should be able to help. Of course it helps if you have a reasonably fast processor so you can transfer the files in the background while you work on something else.

To do any of this you will of course need a computer with soundcard, modem, and an Internet connection. Your first stop should be www.mp3.com, which is a great resource for MP3 players, encoders, plus a FAQ on MP3. You can follow the links for freeware, or you can buy the software on-line. The advantage if you choose to buy is that you get a support line. Expect to pay less than $30 for a “pay” encoder. If you want to download and listen to .mp3 files you will also need a decoder. The most popular one is Winamp, at www.win amp.com.

My choice was Right Click MP3, a freeware encoder/decoder in one program. It’s DOS, so it doesn’t have the pretty little interface, but is absolutely idiot proof to use. Check it out at www.mediabuilder.com/8502.html. It has full control over all settings.

I should point out that there is controversy raging now about MP3 on the Internet. It stems from record companies losing sales, as some copyright material has been encoded to MP3 and put on the ‘net for everyone to download. Maintain proper copyright procedures and you’ll be fine.

There are other audio compression algorithms out there such as Liquid Audio and Real Audio’s new G2. Microsoft is working on MS-Audio 4.0 for upcoming release, which is supposed to compress files to half the size of MP3 with significantly better quality. These may sound better than MP3 as well. The important difference is that someone will own the core of these programs, so you will have to pay for them. MP3, being an open standard, can be had and used for free. Sell that to your GM.

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