Bits and Bytes cont'd--Understanding Digital Jargon for Your
Home Voice Over Recording Studio
So How Do I Send this Digital Audio file?
So you have this gi-normous file and you need to send to your client. How do you do this? If the file is smaller you can compress it into an MP3 file and send via an email. Or, if the files are larger or more numerous you can upload the files to the clients server via FTP.
Using MP3 Compression Delivery
If the file you need to send is short, say a few minutes long, you can compress the file from a WAV or AIFF file into an MP3 file. This will reduce the file size without any perceptable deteriation of the sound quality. For example, using a 128k bit rate, a WAV file will be compressed almost 6 to 1.
There are four parameters the client can ask for when they specify the MP3 format for the final product. These are:
- SAMPLE FORMAT -- usually 16 bit
- SAMPLE RATE -- usually 44.1 kilohertz
- MONO or STEREO -- Use MONO for voice-only recordings
- BIT RATE -- a range from 16k (terrible sound) to 320k (pristine sound) -- usually 128k to 256k
The first two parameters are usually set when you initially record the audio since most recording programs record using a compressionless PCM (aiff or wav) format. So when you begin the project, set these parameters to 16 bit, 44.1 kilohertz.
The second two parameters are set when you actually export the files as MP3s. You want to select MONO because the tracks you record should be mono. You only have one mouth and you use one mic so the recordings are mono. If you select STEREO the file will create two identical left and right tracks from the mono file, thus doubling the file size. Also the client will have to convert it back to mono when they use it.
The final parameter -- BIT RATE -- is often specified by the customer.
Lower bit rates make smaller files but make noisier audio. In order to reduce the file size some data has to be discarded and the more you discard the more the sound suffers . And you can't get the data back once it's discarded. So if it sounds bad you can't make it sound better. This is called "LOSS-Y" COMPRESSION. It's like running a picture through a copier. The copy is not as clear as the original.
Higher bit rates make larger files and make cleaner audio. So when you pick a bit rate, pick the highest bit rate you can as long as you can still email it. The minimum I'll use is 128k. I routinely use 192k. Bit rates higher than 192k don't really improve the sound quality that much but result in much larger files so unless the customer requests a higher bit rate, 192k is the highest I go. 192k will give you about 4 to 1 compression... the MP3 files will be four times smaller.
By the way when the bit rates get up to 256k the file sizes are so close to uncompressed files that you might as well send WAV or AIFF files.
The settings for MP3 conversion are often found in the "preferences" menu of the recording software that you're using. Any files under about 10 Megabytes can probably be emailed without being kicked back by the clients internet service provider or clogging up the clients mailbox. If you have several files that are 5 Megabytes or so you might want to send each in a seperate email. Anything bigger than that... you'll need to use FTP file delivery.
Using FTP File Delivery
For big files things get a bit more complcated. And you need to speak a little internet-ese. So hold on, here we go.
When you look at a web page you use your BROWSER (like Internet Explorer or Firefox) on your computer to access another computer over the internet called a SERVER. If you look at a typical web address or URL you'll see it starts with the strange sequence of letters and symbols that look like this: http://. Well those letters actually stand for words... Hyper Text Transfer Protocol... which means the data coming from the server is the data for a webpage. This called a protocol.
But there's another internet protocol that is used for uploading files to the server in the first place. This is called FTP or File Transfer Protocol. These web addresses start with the letters and symbols ftp://.
But you can just type ftp://blahblahblah into a web browser and access the server. Just like you need a browser application to see the internet, you need an application called an FTP CLIENT to access someone's web server. Once you have that application you can access folders on any web server in the world. Kinda scary, huh?
Well, it's not quite that simple or we'd be deluged by hackers. In order to actually get through to the server you'll need a (you guessed it) USERNAME and PASSWORD. And you need the FTP address of the folder you're trying to access. It looks something like ftp://nameofsite/folder. You'll get this information from the company you're doing the recording project for. Just ask for the FTP address, USERNAME, and PASSWORD.
There are several free FTP client applications available for both PCs and MACs. Just google "free ftp client windows" or "free ftp client mac OS". When you install this FTP client application and launch it you'll see a window that looks like this:
Plug in the address, username (or login here), and password and hit go and VOILA! the next folder you see is on the client company's server. You copy your audio files to this folder and the client company can download your files from their computer immediately. Amazing.
*** IMPORTANT ***
You have a choice of uploading your audio files as TEXT (sometimes called ASCII) or BINARY.
ALWAYS USE BINARY! USING TEXT WILL TURN YOUR FILES TO GIBBERISH!
So for the Biggies Use FTP
Using FTP delivery you can send large files and many files to anyone. It might take a while to upload but you can send hundreds of Megabytes or even Gigabytes anywhere in the world in a matter of minutes.
You'll Need to Know All This Stuff
You don't need to be Bill Gates or Steve Wozniak to do voice overs. But you do need to get your arms around the basics that I've covered here. Often you'll know more about this than your client does so you'll need to explain the options to them and tell them the reasons why. Just wait until some client asks you to email a gigabyte file (gag!) or asks for a 16k MP3 file (yuk!). Nowadays you're judged by your performance AND the quality and delivery of your recording.
You may have to read this article several times to soak it all in but put the work in and you'll be ahead of the game in this brave new world of voice overs.
Finally, the best way to learn this is by doing it. Imagine reading an article about how to paint a house or play the piano. You can pick some tips but to really learn you have to "just do it!" So fire up your recording software, set the right preferences, export some MP3s, and upload some wav files with your FTP application. With a little practice and experience you'll be a digital wizard!
by William Williams
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