record audio
advice for capturing speakers or performances in audio for playback on portable devices later
HOW TO PRODUCE A RECORDING -- Short Version
Location. Choose a good location, as near to source and away from distracting sounds.-Begin recording a little beforehand, so the lead in can be neatly trimmed; ditto the fade out at the end.
Quality. Use the best recording quality setting that will hold the full period of recording (stereo takes twice the storage space as monaural; higher settings (sample rate 64 kilobits per second or higher, sample size 16 bit or higher, ---22.05kHz or higher) take more memory.
Transfer. Move the raw audio content to computer for editing: WAV and mp3 files can be edited on the free audacity program (audacity.sourceforge.net), WMA files can be edited on the Windows Accessory program Windows Movie Maker (suited to video WMV as well as audio WMA).
Edit. Make basic edits: remove dead space or interruptions, make a clean start and end points, consider a fade in at start and fade out at end, for low sound level consider boosting the material with tools such as "normalize" (flattens volume lows and highs).
Distribute. Save As... by setting the output options to give desired compromise between audio playback quality (the better the sound the bigger the file size) and filesize
HOW TO PRODUCE A RECORDING -- The Longer Account
1. Start with good source material: with speaker's permission in hand (or allow them to listen first, to approve the quality, etc), begin by placing the mic nearest the speaker (and shielded from distracting background noises like noisey doors, water glasses being lifted, fans or heaters or LCD projector fans.
2. Choice of hardware: The simplest is a device that natively records in mp3 so you can make a few tidy edits, save the file, then place online. Alternatively, a relatively inexpensive digital audio recorder I've started using is the Olympus ds-30/40/50 (memory capacity goes up with each model). The strong point is cost, stereo mic, quick transfer to computer. The weak point is filetype is WMA (Windows Media--Audio), which works with few editors. I use the utility on Windows XP (Windows Movie Maker, which works on both WM-Audio and WM-Video). The minidisc format has been popular with radio journalists for its super high quality. It gives you WAV files, which all software can play/edit. You'd ultimately want to convert to mp3 for listener convenience.
3. Two editing styles. (1) "As is" - just trim the front end to make a clean start (introducing the speaker; or directly beginning with the presentation) and clean end. A nice touch is to use "fade in" and "fade out" tools in the audio editor (Audacity is free and is well regarded, http://audacity.sourceforge.net). And a professional lead-in or trailer is a nice piece of boilerplate, too: telling the name of the series or sponsoring units involved; giving contact information, etc; maybe even a short signature melody). (2) "Capsule version" - include the speaker's first 5-10 minutes where the argument is outlined, then jump to the finishing portion where the thing is summed up and conclusions are offered.
4. Saving the finished file. Some listeners have good connectivity, so filesize is not a concern. But there are still others of us where smaller is better (to fit on portable player; to minimize download time). The radio people I've corresponded with tell me they tend to use the following minimum standard for audio files:
---bitrate of 64 kilobits per second (kbps; by comparison, pop music downloads are often 2-3 times higher, at 128 kbps or 192 kbps, thus effectively doubling/tripling the filesize).
---sample rate of 22,050 Hertz (cd quality is 44,100 Hz)
---sample size of 16 bit
Of course by going to lower settings you can shrink the finished file even more. And by selecting monaural instead of stereo, you reduce the file by half.
5. Publishing the finished files. Even if you haven't settled on an expedient workflow, at least you can begin to gather the audio for the time being, one event at a time. Then in the future you can arrange these online in one of several ways:
DISSEMINATION OPTIONS:
---cd sent by post (cost paid by recipient)
---email upon request: unless file size is restricted by attachment limitations
---email work-around: use a free temporary host site to hold the file and send requester the URL to download directly (e.g. yousendit.com)
:::: These first three methods give you some record of who is listening
---placing files on one's own web host (so the address reflects your ownership; or to make the original event announcement become a live link to that uploaded audio file)
---placing files on a free web host such as archive.org or one of the podcasting services
including the educational wing of iTunes called iTunesU.
---related method for blogs: the free bloghost, blogger.com, allows video and images, but not audio posting, although other providers may allow audio to go into the blog. The work-around with the no-audio blog is to place the file online elsewhere, but to give its link in the blog entry.
6. Finishing polish. It is good to fill in the meta-data (tags) for the audio file so that anyone who downloads it will see the details like: author, contact (email and/or URL), event details.
updated 12 November 2008... created 12 November 2008