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MP3 Tutorial

To start off this tutorial let's assume that the scenario is as follows: you own a small collection of music CD's and you're interested in the convenience of storing your collection on your PC's hard drive for easy access.

 


 

E x t r a c t i o n

The first step is to extract the audio data from the discs. This is one area that is very important if you want near-perfect quality sound to emanate from your MP3 player. It is a very bad idea to record music from CD's using analog methods - for example, redirecting your CD audio to the line-in input on your soundcard. Music sampled this way is "quantized" by your soundcard's ADC (analog-digital converter), which introduces error. Also, the music can often end up too loud or too quiet and needs to be "normalized" to play at a decent volume level. Normalizing is a mathematical process and again, technically results in impure sound. Recording using this method will sometimes be necessary, e.g. to encode live concerts from DAT tape or similar. It might also become necessary if your CD-ROM drive is not capable of digital audio extraction. You can find a partial list of which CD-ROM drives support this process by clicking here (courtesy of MP3.com).

If your audio source is music CD's, there is a much better way to copy the audio tracks. Programs known as "CD rippers" will extract audio tracks from CD's digitally, meaning (generally) zero-error and mathematically perfect CD quality sound. CD rippers generally save the audio in a standard pulse-code modulated (PCM) format such as WAVE.

For this purpose, we recommend WinDAC 1.41 or later, or alternatively Audiograbber 1.3 or later. It is up to you to decide which to use, as one will often work better with your CD-ROM drive than another. If your CD-ROM drive seems to have difficulty extracting audio using the aforementioned software, it might be an idea to invest in a SCSI CD-ROM drive. The SCSI interface allows constant as opposed to variable transfer rates which is important for audio extraction. WinDAC and Audiograbber are very simple programs, and you should have no problems working out how to copy audio tracks to your hard drive. It is important that they are saved as 16-bit 44khz stereo PCM WAVE files to ensure that all encoders will be able to read the audio data. Even if your software allows, do not resample the tracks to 48khz - this is a waste of space and some encoders will not be able to read audio data sampled at 48khz. Also note that CD tracks take up a huge amount of space on your hard drive, so make sure you have at least 10 megs for every minute of audio you would like to temporarily store on your hard drive (before it is encoded).

Once you have the audio tracks extracted from CD onto your hard disk in WAVE format, move on . . .

 


 

E n c o d i n g

For the process of encoding your music into MP3 format, we recommend only one encoder - XingMP3 from XingTech Corporation. On a fast Pentium II machine it will encode an entire CD worth of music in as little as ten minutes (eight times faster than its closest rival). You might hear from uninformed sources that XingMP3 is as fast as it is because it fails to encode frequencies above 16khz. The 16khz limit is academic, as it doesn't affect audible sound quality in any way - and it is impossible that this alone could make Xing as fast as it is. If you're not convinced, read more about this topic here. XingMP3 is a commercial product however, and sells for USD$19.95. You can buy it from their website - it's much less expensive than its rivals.

A freeware encoder you might like to check out is called BladeEnc. It is quite fast, but its sound quality and speed are no match for XingMP3. BladeEnc is available on the Audio Forge encoders page.

At this point, we're going to assume you've decided which encoder you'd like to use and you have your WAVE files extracted from CD residing on your hard disk.

As we mentioned before, with some software it is possible to resample your WAVE files from 44.1khz to 48khz. As with your CD ripping software, if your encoder supports it - do not use it. It technically cannot make the quality of your music any higher and only wastes space.

The most important point to consider when encoding MP3's is which bitrate to encode at. The generally accepted "industry standard" is 128kbps (kilobits per second). Unless you have a really cheap pair of speakers, we recommend encoding with XingMP3 at 192kbps (unfortunately it does not have a 160kbps option), and also at 192kbps with BladeEnc. Playing back Xing-encoded 192kbit MP3's through a $6,000 stereo system results in audio of a quality indistinguishable from the original CD signal. Most encoders will be able to achieve this at a bitrate of ~256kbps.

Once you have set the bitrate you'd like to encode at in your encoding software and selected the WAVE files you ripped earlier - set the encoding process going. On a Pentium II system, you're looking at 10-15 minutes to encode all the WAVE files using the XingMP3 encoder. With BladeEnc or MP3 Producer Pro, this process will take around one to two hours. Some very slow encoders may take up to 12 hours!

Once the MP3's have successfully been encoded, it's a good idea to delete the old WAVE files and rename your MP3's to give them a meaningful name. Adding an ID3 tag (a small tag at the end of the MP3 file which contains information about the music) is generally not necessary unless you name your MP3 files poorly. We recommend naming your music in the following way:

track_number-artist_name-album_name-song_name.mp3

for example:

01-pearl_jam-yield-brain_of_j.mp3

would correspond to Pearl Jam's first track off their Yield release, Brain of J.

Legal issues: It is important to note that you are legally not allowed to distribute MP3 encodings of commercial music. It is quite okay to encode CD's you own to MP3 format for convenience, but not to distribute or broadcast them. What you choose to do with your MP3's is at your discretion - MP3's themselves are NOT illegal! It is what you choose to do with them that makes that particular use illegal.

Now that you have your MP3's, how do you play them? Read on . . .

 


 

P l a y b a c k

When it comes to top-notch MP3 audio players, there really is no competition. The best player out there is without a doubt Winamp by Nullsoft. An estimated half a million people around the world use Winamp to play their MP3's.

Winamp is a fully-featured player that supports many formats, including modules such as XM, IT etc. As an MP3 player with a parametric graphic equalizer, window and full-screen visualisation and low CPU usage, it just can't be beaten.

Speaking of speed, it is important that you have a machine with a fair amount of grunt to play MP3's and work in other applications. You can get by just listening to MP3's on a high-end 486 (DX4/100) or a cheap Pentium clone. However, decoding MP3's is such a CPU-intensive process that this will use nearly all of your CPU cycles and you will not be able to work in other applications in the background. On modern Pentium systems, this CPU usage is barely noticeable (as low as 5%) so you will be able to work quite happily while playing your MP3's at the same time.

At this time, there are two players that might just give Winamp a run for its money - Sonique and Digideck. Sonique was recently released and has been highly praised for its awesome animation and functionality. CPU usage is a little high, but Sonique is definitely worth checking out. Visit the Sonique home page by clicking here.

Digideck arrived on the scene recently with astoundingly low CPU usage in a very small package. It's lacking in features, but on moderately slow systems Digideck is worth a try. The Digideck homepage is here.

All of the above players are more-or-less free (Winamp costs US$10 to register but is not cripple- or nag-ware).

That's all you should need to know to start enjoying having your music collection at your fingertips using the amazing MP3 format!

Any comments or suggestions regarding this tutorial can be e-mailed to webmaster@audioforge.net.

Click here to go back to The Audio Forge.
Copyright © 1998, Netherworld Media. All Rights Reserved.

 


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