PoducateMe: Practical Solutions for Podcasting in Education
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Printable copies of the guide are available for purchase and immediate download at
CareerChat, but we’ll be making the switch to VBR with our next episode. Most all media
players now fully support VBR encoded files, so it just makes sense for us to take
advantage of its benefits.
For voice podcasts recorded with a sample rate greater than 32kHz (we recorded using
44.1kHz), the following switch settings will yield good results for a voice podcast:
-V7 --vbr-new -q0 -B192 --lowpass 15.5 --lowpass-width 1 --resample 32
Let’s examine the function of each of the switch settings. These settings largely
determine the size and sound quality of the resulting MP3 file. Generally, the better the
quality, the larger the resulting file size, so it’s important to try to strike a good balance
here. The above command line tells the encoder to perform the following processes on
our AIFF file as it converts it to the MP3 file format:
-V7: On a quality scale from 0-9, with 0 yielding the highest quality, use 7.
--vbr-new: Encode using newer and better VBR standards.
-q0: On a noise shaping quality scale from 0-9, with 0 yielding the highest quality, use
0. Noise shaping reduces artifacts introduced into the recording during
compression by pushing the noise outside the audible range of the frequency
spectrum.
-B192: Use a minimum bitrate of 192kbps.
--lowpass 15.5: Cut off frequencies above 15.5kHz.
--lowpass-width 1: Set the frequency range to be affected by the lowpass filter.
--resample-32: Change the sample rate from 44.1kHz to 32kHz.
There are many different switches and settings from which to choose—we’ve merely
scratched the surface of the power of the LAME encoder here. Visit the LAME area on
Sourceforge.net for a comprehensive list of LAME switch settings
Because we’ll be using Max to encode our file, we won’t have to input switch settings.
Max makes encoding easy, but does so at the expense of allowing the user greater
control over the process.
After downloading Max, launch the program and perform the following actions:
1.
Select File > Convert Files from the menu bar.
2.
Locate and select the AIFF file you want to convert. The file will open in the
window shown in Figure 72
