Streaming Audio Primer
(Part 2):
You will need the following stuff to make your
recordings:
Needed Materials for Hardware Setup
- Original Audio Recording (Tape, CD
format, or Live).
- Computer (faster will save you more time)
with at least 275 MB of free space.
- Cable to connect Tape, CD player,
microphone, etc. to Computer's Sound Card.
- Sound Recorder/Editor software.
- Encoding software.
- 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:
- 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:
- 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.
- Once you have your hardware setup, start
playing your tape/CD player and press the "Record" button in
the CoolEdit window.
- 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.
- 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.
- 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. |