Streaming Audio Primer (Part 2):
How to Digitally Record Audio Files

You will need the following stuff to make your recordings:

Needed Materials for Hardware Setup

1. Original Audio Recording (Tape, CD format, or Live).
2. Computer (faster will save you more time) with at least 275 MB of free space.
3. Cable to connect Tape, CD player, microphone, etc. to Computer's Sound Card.
4. Sound Recorder/Editor software.
5. Encoding software.
6. Web page Space.

Setting Up Your Hardware

Depending on the type of recordings that you wish to make, your setup may vary from mine; however, the basic setup will remain the same. Each setup will have some kind originating audio source, such as a tape player, CD player, Live microphone output, etc. This source will need to be connected to the input of your sound card on your computer by way of a cable, possibly using some adapters. Finally, you will need recording software to actually record the audio.

Now that you have an idea of the hardware setup, follow the directions below depending on the format of your original recording.

• CD FORMAT: Few people have sound bytes previously recorded in CD format; so if your original recording is in another format, skip to the next section. But, if you have a CD-ROM copy of the desired audio, then you can use a program called a stripper, to "strip" data from the CD and turn it into a WAV file. I have only used a shareware version of Audio Grabber and Audio Catalyst. I am aware of other strippers.

  Please check the site below for a list and review of shareware versions of other strippers. Once you have mastered the use of your stripper software and produced a WAV version of the audio, then you will be ready to skip to the next section: Noise Reduction.

  However, you may not need to reduce the noise of your recording if the original was high quality. Please see the following pages for more details on strippers and related software:

  The "Updated Daily" MP3 Page
  MP3.com

• ALL OTHER FORMATS: First, you will need to locate the connection ports on your originating source and the sound card on the back of your computer. On your originating source, look for some kind of output port, like a headphone receptacle or, even better, an RCA Line Out port. On your sound card look for some kind of Line In port. A microphone receptacle will work, but a Line In port will be better. Once you have done this, then you will need a cable, and possibly some adapters, to connect your source to the sound card. I bought a 6' cable from Radio Shack that will plug into the "HEADPHONES" receptacle on my tape player and an identical LINE IN port on my sound card in my computer. For you it may take some time at Radio Shack, or a similar electronics store, to find a cable that will match your system, since everybody's setup may be a little different. If you cannot find a pre-manufactured cable to fit your system, adapters, connectors, and other neat gadgets can be purchased from Radio Shack to adapt a cable to fit your system. Expect to spend between $5 and $10 on this step.

Recording your WAV File

Once you have completed your hardware setup, you will need a program to record and edit your audio files. Usually the sound recording software that come with your computer does not support high sampling rates; i.e., they make lousy recorders with few options. I know of three packages designed to make great recordings:

• Cool Edit 96 - This program comes in two versions, Cool Edit 96 and Cool Edit Pro. You can download a shareware version of CE96 and a demo of CE Pro. The shareware version of CE96 is free, but it is also crippled. To help motivate you to register the software, the shareware version comes capable of using only 2 of its 6 sets of features. Every time you run the program, it lets you pick 2 of if its feature sets. One of these must always be the recording/saving set. Without this option, you will be unable to record from your connected player and to save any changes made to a previously recorded sound file. The other set that you will use frequently is the "Amplifying/Normalizing set." To take advantage of other sets, you must save your changes, close the program, reopen it, and choose the desired set. If you don't like doing this, registering will put you out $50 ($33 for students). This is the one that I recommend and describe below.
  
  
• Cool Edit Pro - The demo can be downloaded for free, and it is much nicer than the regular Cool Edit 96. CE Pro supports 32-bit sampling (CE 96 only supports 8- and 16-bit). It also has a nicer interface and much more features. Unfortunately, the demo is severely crippled and will not allow you to save any files that you may record or change. But, its nice for exploring. To register this package will set you back around $399! Because of this I would recommend the CE 96 version; it will have all you need for this purpose.
  
  
• Gold Wave and Sound Forge - These are two other packages. I have used neither of these. I found all I needed in CE96, so I didn't really investigate these much. Gold Wave comes in a shareware version, similar to CE96. A BETA version of the newest version of Gold Wave can be downloaded for free too, but the programmer warns of known errors and not to use the BETA if you want to do real work. It's only for playing around. Sound Forge can be downloaded as a demo, but the demo version can neither record or save.
  

If you do use Cool Edit 96 to record audio files, here are some abbreviated instructions:

1. Choose "Open Blank Sampling Instance" and pick the fastest sampling rate (48000 Hz) and the Mono Setting. The 44,000 Hz sampling rate is slightly more universal. If a later applications states that it "cannot support sampling rate" or something like this, try using CoolEdit to "Convert Sample Type" to 44,000 Hz. This is the sampling rate on all music CD's. So, use the 44,000 Hz rate if you plan on putting the audio onto a CD.
   
   
2. Once you have your hardware setup, start playing your tape/CD player and press the "Record" button in the CoolEdit window.
   
   
3. After the tape is finished, press "Stop" in the CoolEdit window to stop the digital recording. If you notice that the audio is not centered about the red horizontal line (zero), then try turning off your computer and player, unplugging the dubbing cable, turn equipment back on, and finally plugging the dubbing cable back in. Sometimes either the cable, card, or line port develops a static charge that can only be removed in this fashion. This static charge cause the entire audio file to be shifted above or below the red horizontal line.
   
   
4. Select the entire the wave: go to "Edit" > "Select Entire Wave". Go to the "Transform" > "Amplitude" > "Normalize" menu. Select 100% normalization and "0% DC Bias Adjust". This will make the recording louder without having to be turn up the volume when being played. Also it will produce higher quality audio during playback, because it reduces noise from analog amplification during playback on all players. Once you click OK, the computer will have to churn for a while. CoolEdit does a good job of predicting the estimated time left.
   
   
5. Finally, save your new sound bite. Click on "File" > "Save As" and choose the format as "Windows PCM (*.WAV)". This will save the sound bite in an uncompressed format. A 45 minute sound bite will take up about 250 Mbytes of space at 16-bit, 44 kHz, and Mono settings.

Once you save the audio file, then you are ready to remove that nasty 60 Hz hum, or any other type of background static. However, you may want to jump over the next step if this your first time through the process - just to simplify the first attempt. Also skip to the encoding step if you are satisfied with the quality of your recording. However, please note that background noises become amplified during the encoding process, so your finished product may be unacceptable if this WAV recording was marginal, or tolerable. Most people will need to do some kind of noise reduction, so proceed to the next step to learn how to use CoolEdit to remove that annoying background noise.

Part 1: Introduction
Part 2: Digital Recording
Part 3: Reducing Noise
Part 4: Encoding
Part 5: Web Pages

Reprinted with permission from author Trevor Bowen, whose Web site contains good information on utilizing the digital medium.