MP3 your music - a primer on what to do and how to do it

By David Miles Huber

This is a really useful place to start with MP3s or even refreshing a few old memories. Many thanks to Dave for this great piece.

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Real-world applications for audio production
MP3 your music!
by David Miles Huber

I know that many of you have heard that people are using the MP3 compression format to encode their album/CD collection. But how many of you have actually taken the time to transfer a CD, record and/or cassette to mp3 and save it to hard disk? Well, I'm currently in the process of doing this to my entire collection... and it's revolutionized the way that I listen to music.

First off, not only can I squeeze 10 CDs or more worth of data into the same 650Mb space, I can categorize my music according to genre by creating and storing my music in a directory structure like this:

So what are the big advantages to MP3ing your collection?

It's much easier to access your entire music collection - Gone is the need to rummage through your entire CD/record collection to find the music you want. By classifying your music styles into directories, finding and playing the music that hits your current mood is literally just a few clicks away!

For example, most MP3 software apps let you organize the songs in a CD or collection into a "playlist", which can be saved as a playlist file. Entire playlists can then be "dragged" into a new playlist, allowing you to consecutively play through any number of albums, radio programs, etc. In this way, you could pre-program an entire day or evening's worth of music to work, relax or play by.

It's easy to create file backups - By categorizing your music according to style and then creating sub-directories (i.e. Salsa Disc 01) that are each close to 650Mb, you can backup each directory to a CD-R for safe keeping and/or to play on the road from an MP3 CD player or laptop PC.

Remember it's always wise to make extra backup CDs, just in case!

Download the files into your portable player! - Files can be easily downloaded (often in a drag-n-drop fashion) into a portable, solid-state MP3 player and taken on the go, without having to deal with bulky CD cases, etc.

Quality Issues
The simple fact of the matter is... the higher the playback quality, the lower the compression level... meaning that an encoded song will use up more data space. Bottom line is that compression algorithms like MP3 will always battle between the issues of quality vs. filesize.

Let's start off with the basic fact that not all MP3 encoders are created equal. Many "rippers" will use their own encoding scheme that closely approximates the original, German Fraunhofer MP3 codes. The encoding quality of the original code is often far better, when compared to lesser, quality rippers. All sales pitches aside, you'll end up with the highest possible encoding quality and will be able to make use of CE 2000 and CEP's batch processing options if you spring for the $29.00 and get the Syntrilium's MP3 plug-in.

Encoding MP3 at 160kps (killobytes per second), 44.1kHz, 16-bit Stereo - Using the original Fraunhofer codes, 160kbps, I actually can't hear much difference between the original CD and the MP3 file... HONEST! So much so, that I've encoded all my favorite CDs at this rate. The compression rate seems to work out to about 10:1, meaning that 10 CDs worth of sound can be stored in a 650Mb space.

Encoding MP3 at 128kps (killobytes per second), 44.1kHz, 16-bit Stereo - For records, I'll always use 128kbps compression. There's a bit of quality loss over 160 kps, but it's adequate to capture the sound of most records. If you don't feel that way about your record collection, go ahead and process at 160 kps. I don't recommend your going below 128 kps, unless you're just archiving sound or saving a radio program.

Encoding Windows Media Player format (.WMA) at 64 kps, 44kHz, 16-bit Stereo - To me, Windows Media (WMA format) sounds about as good as MP3 at 128 kps. This is amazing, given the fact that the file's encoded at 64kps! This means that 50% or more sound can be squeezed into the same memory space. For those who use portable media players, memory space is a very important issue!

Encoding Windows Media Player format (.WMA) at 22 kps, 22kHz, 16-bit Stereo - What can I say, it's pretty lo-fi... best used for auditioning purposes or for encoding radio shows. Not recommended for CD or record encoding.

Media formats, Encoders and Players

The following sections offer a basic intro to what is a fast-growing and important part of music production, distribution and consumption.

The most commonly used formats for encoding and compressing audio are:

  • MP3 - MPEG II/Layer 3 (developed by the Fraunhofer Institute in Germany) is by far the most commonly used encode/decode format that's in use today. Usable compression rates range from 40kps (low) to 160kps (high).
  • WMA - The Windows Media format was developed by Microsoft for use with their Windows Media Player (although many players are now capable of decoding this format). This format supports two compression rates: 22kps (pretty lo-fi) and 64kps (which is roughly equivalent in quality level to MP3 at 128kps... an amazing feat, as it only takes up half the memory space!)
  • AAC - After MP3 was finalized, work continued to develop a higher quality coding/decoding process, as a result MPEG-2 Advanced Audio Coding, or simply AAC was developed. AAC claims to provide greater levels of data reduction over MP3, while reducing audio artifacts at extremely low bit rates. In addition, AAC is a multichannel encoding process, allowing 5.1 (surround) and more channels to be encoded into the bitstream.

    Encoders
    Currently a wide range of software encoders are available. These can exist as a stand-alone package or can be integrated into a software editing or audio application. When choosing an application to encode MP3, I recommend that you use one that has been built upon the original Fraunhofer codes (as is the Syntrillium MP3 plug-in).

    One application that can encode .WAV into .WMA files has been jointly created by Microsoft and Sonic Foundry is the "Windows Media On-demand Producer" and is available free.

    Players
    Of course, there are a lot of media encoders, players and jukeboxes on the freeware, shareware and commercial markets. These software apps range from being a clunky interface that takes over your PC to simple and elegant systems that do their job well. The choice is, of course, up to you... however my personal favorite player is Winamp. It's free, simple and works great! The site includes an amazing array of free skins and visualization eye-candy that interacts with the music. Another is the Windows Media Player from Microsoft. It's simple and has a number if built-in skins and visualizations that can be expanded using other plug-ins which can be downloaded from their and other sites.

    MP3 CD Players
    The ability to play MP3 files from a CD player is one of the best concepts to come along in a long time. The ability to play 10+ hours from a single CD has obvious advantages over the traditional CD. Here are a few of the player system types that are coming onto the market:

  • It goes without saying that PCs make great MP3 players (this is especially true for laptops that can easily be taken on the road).
  • Newer portable CD players are now available that can let you take your MP3 files for a jog or a ride.
  • Certain DVD home-theater players are now capable of playing MP3 files.
  • Hopefully, car manufacturers will soon get on the bandwagon and design MP3 into car players.

    MP3 Solid State Players
    Speaking of MP3 players, the data can be quickly downloaded into a solid-state MP3 player, letting you take your favorite music to the streets without having to deal with bulky CD cases, etc.

    The obvious advantage of these players in their portability and insensitivity to skipping. If you have a PC or laptop with you, you can quickly download MP3 or other format files into the player (giving you access to your music collection without having to lug CDs around.

    The downside is the fact that memory is often expensive; a fact that often limits memory size to 64Mb (about 55 minutes at 160kps). Having a player that reads .WMA files can more than double the playtime at 64pks.

    A major consideration, when buying a player, is the choice of memory media type. For, example, I have a digital camera that uses the "Compact Flash" memory media. As a result, I got an MP3 player that uses the same memory type. The fact that the player has a USB card reader, allows me to take the card out of my camera and convert/process pictures much more easily... such considerations should be carefully made when choosing a player/media type.

    Batch Processing
    In multimedia production, one of the more common day-to-day tasks includes the need to convert a large number of files in an existing format to another format. This tedious process can be automated and sped up by using a "Batch Processing" utility. Of course, Cool Edit 2000 and Cool Edit Pro lets you batch process any number of source files in any way, including: converting .WAVs to MP3, effecting files, changing pitch/time, etc... and then convert then to a wide range of available formats. The basic directions for "running a batch" are:
    1.Open the "Scripts and Batch Processing" window (Options/ Scripts and Batch Processing)
    2.Select Batch conversion from the Scripts Collection window.
    3.Select the source files - Open the files from the newly created program directory and select the files that are to be batch processed.
    4.Select the destination directory - Select the directory that the processed files are to be saved to.
    5.Select the output format - Select the output format (MP3, etc.) that the processed files are to be saved in. Select the Options button and choose the compression rate that the files are to be processed and saved at.
    6.Disable Undo - This causes CE 2000 or Cool Edit Pro not to save undo files during the batch process phase (essentially, this acts as a time saver during the batch run).
    7.Run the Batch Processing script.

    Any number of complex processing and encoding steps can be automated as a batch function by following these steps:
    1.Open a file that can be processed as you'd like future batch files to be processed/saved.
    2.Open the "Scripts and Batch Processing" window (Options/ Scripts and Batch Processing)
    3.In the top right hand-side, enter the name of the script (functions) to be recorded.
    4.Press the Record button (the dialog box will clear).
    5.Begin any number of processing and/or file encoding moves that you'd like to be encoded in the "script" from beginning to end.
    6.Once done, simply recall the "Scripts and Batch Processing" window (Options/ Scripts and Batch Processing) and select << Add to collection >> (this will save the script) or Clear (will erase the script, allowing you to cancel the operation or record the script moves again)
    7.At any time in the future you can select the script and have it perform its moves on any number of files (in the same manner as the batch processing section above).

    The batch process can be sped up by:
    1.Turning off the Enable Undo function - This causes CE 2000 or Cool Edit Pro not to save undo files during the batch process phase (essentially, this acts as a time saver during the batch run).
    2. Unchecking the "Pause at dialogs" button - which would otherwise cause Cool Edit 2000 or Cool Edit Pro to pause at each processing dialog step (often a source of nuisance).

    Dave (who is an avid techno-evangelist for Syntrillium) has finally finished the update of his best selling book "Modern Recording Techniques" (www.focalpress.com) to its 5th edition. His musical explorations can be found at www.51bpm.com

    (c)2001 Syntrillium Software Corporation


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