For the last few weeks, we’ve been talking about getting recordings in, and managing them on, your computer. What do you do with them once they’re there? How do you make them the most useful for your purposes, whether for the audience, your own listening or your musicians’ practice? If you want to get it from your computer to your groups’, or put it online for the world to hear, you should consider how you save the file to make it easier to distribute. It’s important to remember that neither one of these steps are truly “necessary”– today’s recording equipment or software usually does a pretty good job of giving you an audio file that you can use immediately. Understanding these two steps, though, will go a long way to helping you master the distribution of your audio.
Formats, Files and Bits (Oh My!)
Files on your computer take up space. Not physical space, but “virtual space.” The space taken up by a file affects how many of them can be stored on your computer and how you can transmit them from one file to another. Storage space in computers is so relatively cheap now that it’s very hard to fill up your computer with the types of audio that you likely record, but there are still some real-world considerations about file size. For example, did you know that…
- E-mails have a size limit? Text alone will almost never fill this limit, but a big audio file might!
- Bigger files download slower? Especially if your musicians are going to listen to the file on a smartphone (iPhone), it can take time to download a big audio file.
- Free websites often have a limit to how large your free website can be?
Don’t panic… You can send all the music that you want, but we just have to be a touch smart about how we do it. Thankfully, most audio programs give us two ways to handle how big the audio will be. You’re going to make one judgement call about your audio, and that’s going to inform two decisions about your files.
Remember when I said this wasn’t really necessary?
It’s not. Don’t let this stop you from plugging in a recorder, taping your rehearsal, and hitting “send.” Consider this Recording Basics Level 2. If you’re already intimidated, have no fear, forget all of this for now and come back next week when we talk about editing and sharing.
Why does everybody love MP3s?
The most basic way to control the size of the file is to control the type of file used. Remember VHS vs. Beta? Two different types of delivering the same information (a movie). Think of file types the same way– different ways that programs can save the same information (your audio). There are many common file types with names like AAC, OGG, Quicktime and AIFF. For your purposes, there are two important ones to remember: WAV and MP3. WAV is a very high-quality file. It is the nearest common file type to “CD Quality.” Unfortunately, it’s also quite large. MP3 is a (very!) slightly lower quality file. For that (very!) small quality difference, it’s considerably smaller.
It’s important to note that most people, given the blind taste test, can’t tell the difference between a good WAV and a good MP3 recording. We’re talking about tiny differences here. If you are recording something where every little ounce of quality counts (audition tapes, choir demos, your new CD), you may want to record and save in WAV. For virtually everything else, though (sending out practice tapes, putting things online, recording rehearsal to listen to later), MP3 should be your file of choice.
Check in your audio program’s Preferences/Settings/Option menu, or look in “Save As…” or “Export As…” to find out what kind of file your program is saving your audio in.
Bit Depth, Sampling, and the Science of Sound
Think back to our VHS vs. Beta example. Even once you’ve chosen a file type, there are more ways that you can customize your file to be a tiny file that’s on everyone’s phones in seconds, or a beautifully immersive audio file with each nuance of your cathedral captured. Remember how VHS recorders had multiple settings (EP, LP, SP) that would let you record either more video, or higher quality video? We use the same concept in audio, except that we control it with two variables: Bit Depth and Sample Rate. Each of these are the controls which alternate between higher quality, but larger, files and those which are smaller, but lower quality. Again, in your Preferences panel, or in the Save/Export options, you’re going to get to choose how big/high quality you want your output to be.
Consider:
- Bit Depth. “CD Quality” is 16-bit. Higher bit depth (24) = bigger file, higher quality. Smaller bit depth = smaller file, lower quality.
- Sample Rate. “CD” is 44.1 kHz, or 44,100 Hz. Same thing here: the higher you go, the better/bigger the file gets.
So What?
All of this gets us to the bottom line: first, make a decision around two questions. 1) Are there limitations on how big your file can be? 2) Are there reasons why you need it to be extremely high quality? From there, you can choose either WAV (CD Standard) or MP3 (Perfectly functional and much smaller). Then, choose whether you want to drop the Bit Depth and Sample Rate to save more space.
Finally, remember that in the never-ending quest for high-quality recordings, the file type is a relatively small decision compared with things like microphone placement, microphone quality and the like. For most “functional” recordings though, the ones that we do just for people to use for average functions instead of trying to record performances, this is an easy way to make your files more easily shareable, whether you do it by web, e-mail, flash drive or any other method.
Jeff Tillinghast says
Jeff Tillinghast says
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