As I was getting ready to leave for ALA Midwinter 2009 in Denver, I found myself packing an almost absurd amount of electronics. For those who don't know, I'm mostly responsible for the podcasts that show up from time to time on LITABlog. For the last few years I've been capturing the audio for programs like Top Tech Trends, and manipulating it so that it can be delivered to the fine people out on the Intertubes.
I realized as I was packing that I never posted about the tech involved, and who doesn't like a great tech-roundup post? So here we go: How I podcasted from ALA Midwinter 2009.
Nothing really happens without my Black Macbook 13", running OS X 10.5.6. For actual audio capture, I love the simplicity of Audacity. I've done some capture in Garageband before, and if its my own presentation I'm trying to record, I actually use the built-in record feature of Keynote. But for the basic "I need this audio", I almost always swap back to Audacity. It's free, and open source for all major platforms.
You can't get good audio without a good microphone. When I'm capturing ambient audio, I use a Blue Snowball USB microphone. It is a little bulky, but does a great job capturing good audio, even in a huge room and with omnidirectional sources. It just plugs directly into the Macbook, doesn't need any external power, and does a great job.
If I'm capturing just myself, I often use another product from Blue, the Snowflake. It's a portable version of the Snowball, but is more directional. Works amazingly for interviews or voiceovers, though.
In the case of something like Top Tech Trends, where the venue is normally a room large enough to need a sound system, the very best sound will be gathered from plugging directly into the AV, rather than capturing over the air to a microphone. To that end, I've put together a little package of connector cables that I travel with, all with the goal of getting the audio directly off something and into the minijack on my Macbook. These include RCA -to-minijack, 1/4" mono RCA adapters, XLR -to-minijack...in all, maybe 6 different cables all with the goal of ending up at a minijack and coming into my Macbook. With these, more or less regardless of the AV system, I can hijack the audio into my computer.
Once I've got the recording, I normally listen through sections in Audacity, paying attention to where it't too loud or too soft, and run a Normalization filter on it. This averages out the sound, bringing the louds down and softs up. I might also clip the beginning and the end, to make it more compact.
The files are then saved to MP3, and I check the file sizes, adjusting the bitrate down a bit if the sizes are just ridiculously large. There's no absolutes to this, just playing around with the sizes. Voice doesn't really need much bitrate to still be good quality.
Once I get a file that looks like it will work, it gets uploaded to the LITABlog media folder with my FTP program of choice, Transmit. I type up a new post, and use the Wordpress plugin PodPress to attach the MP3. PodPress notifies iTunes that there is a new podcast, and adds the enclosure to the RSS feed, and also adds the in-line player to the post.
And then, finally, you get to listen to it.