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7/29/2019 Creating MP3 Music Files

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Beginners Guides: Creating MP3 Music Files

Everyone has heard of MP3. For the last 5 or 6 years, it has been the most publicized

topic concerning the computer world. From MP3 sharing vs. theft and RIAA lawsuits tothe ease and convenience of carrying your entire musical library with you wherever you

go, MP3 has got people's attention.

Like many popular computer subjects however, it is not necessarily widely understoodonce you get past the sound bites and buzzwords. Ask anyone off the street about MP3s

in the news, and you will no doubt get a knowledgeable nod and an opinion, but askthem what MP3 files really are and how they are made, and you would be more likely toget a shrug than facts.

There is a lack of easily accessible, non-technical information about what MP3 files are,how they can be made and used, and the legal issues surrounding them. In this guide,PCstats aim to clear up those questions, starting with an easy definition; what is an MP3

file?

An MP3 file is a compressed version of a digital audio recording, such as a track from aCD. The original song data is 'encoded' using a variety of techniques that reduce the size

of the resulting file while preserving much of the (perceptible) sound quality of theoriginal.

Perceptible sound quality?

Digitized audio is governed by bit-rate, or the amount of song datathat is transferred per second to the

device that is playing the song. A

digital audio recording using the'Redbook' audio CD standard uses1.4 million bits of data per second.

This is the amount of informationnecessary to play a virtuallyidentical digitized version of theoriginal analog music.

The MP3 format reduces this bit-rate by a factor of ten or more, while retaining much of the essential qualities of theaudio. The secret to this is analyzing the frequency of the sounds contained in the CDtrack.

Any audio recording is likely to contain various noises, incidental or otherwise, that areof a frequency we cannot perceive. Likewise, any multi-track audio recording is likely to

have portions where one track drowns out others due to its volume at that point. MP3encoders analyze the frequency pattern of an audio file and filter out sections of the filewhich would be difficult or impossible for us to hear.

Essentially, the MP3 format reduces the size of audio files by 'biasing' them for humanhearing, stripping them down to the essential, easily audible frequencies which would beall we would generally hear anyway. The resulting file is then compressed using moretraditional software methods.

We can levy some control over the sound quality of an MP3 by adjusting the samplingfrequency (typically 44kHz) and bitrate (64kb/s - 196kb/s, and in some cases as high as

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320kb/s) when the MP3 audio file is originally being encoded, which can dramaticallyimpact on the end result. Though just as vinyl records are considered superior to theCompact Disk, CDs are superior to most MP3 recordings; choosing the right encodingsettings narrows the gap significantly however.

How to Create MP3 files from CD audio disks

Creating MP3 music files requires the use of a CD 'ripping' program, software that canencode your music CDs into the much more compact MP3 format. While Windows XP

technically provides this ability with recent versions of Windows Media Player, we havehad much more luck using freely available third party software. For this article we chosethe dBpowerAMP music converter software, based on its ease of use and popularity. Thispackage is freely available from download.com, among other places.

Now we'll go over how to create MP3 files from your CD collection. We'll do it the quickway first, then go over some of the options available to you after that.

Creating MP3s part 1: the quick and dirtyway

Once you have downloaded and installed thesoftware, open the 'DMC audio CD input' shortcutfrom the desktop or start menu.

This program enables you to extract music filesfrom your audio CDs and turn them into MP3 files.

First things first. Insert an audio CD into your CD drive. For the purposes of this tutorial,we recommend you use a CD that is at least a couple of years old, as many newer CDs

use some form of copy protection which will prevent your drive from reading themcorrectly. We discuss this issue later in the article. Notice that after a couple of seconds,the CD title and a track-by-track song listing appear, assuming you are connected to theInternet.

Music converter, like most other CD ripping programs, connects to one of the Internetmusic databases and downloads information on your audio CD based on an ID numberfrom the disc. Rather convenient.

All you have to do now is check the individual tracks that you wish to convert into MP3files and press the 'rip' button in the top left corner. The software will automaticallyextract and convert the selected tracks into MP3s and place them in the 'C:\Converted

Music' directory. That's it. Rinse and repeat.

Creating MP3s part 2: getting into the details

First let's find out how to create your MP3s in a specific location on your hard drive andchange how they are named.

With audio CD input still open, click on the 'options' button in the menu bar.

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The 'output to' option allows you to set the directory the MP3 files will be created in.

Encoding level vs. sound quality

With the 'file creation' box, you can change the naming format of your MP3s.

Pretty self explanatory...

Close the options screen for now; let's move on to the various options available for

actually encoding the MP3 files from your music:



Encoding level (bit rate) vs. sound quality and size

Given that the 'bit rate' of an MP3 file is a direct measurement of how many bits of datathe file transfers to the player for each second of the song's duration, you can see howthis would affect the overall sound quality.

More data per second means more of the original sample of the song is being retained,

which means higher sound quality... and so it does, to a point. The point is, audio is asubjective thing, and one person's take on how a particular song sounds encoded at acertain bit-rate will be different from another's opinion. It also weighs heavily on thequality of headphones or speakers you listen with.

With a pair of standard 'earbud' headphones for a portable MP3 player it really won't

matter much if you choose 128kb/s, or 196kb/s. However, if you're a bit of an audiophileand intend to play back MP3s on a pair of Grado's headphones, you're much better off choosing the highest quality encoding rate possible. I swear by my Grado SR-80s, butthe 'digital slurr' of a low quality MP3 certainly doesn't have anything to hide behind, sothey can be unforgiving.

Most MP3 creation software will give you options for various bit-rates to increase ordecrease the size of the file created and commensurately increase or decrease the soundquality. There are several common bit-rates that are widely used, and most softwaresticks to these ass they provide a wide range of quality and file size options.

64Kb/s: discernibly lower sound quality than the original CD recording, in general.Produces really small files though. 22 - 1 compression ratio.

96Kb/s: Considered 'near CD quality.' You will probably be able to tell the differencefairly easily between a file of this bit-rate and the original, at least if the original has a lot

going on musically. 14 - 1 compression ratio.

128Kb/s: The border of what is considered 'CD quality' sound. Not co-incidentally, this

is also by far the most popular bit-rate used to encode files, especially on the variouspeer-to-peer services. Delivers an 11 - 1 ratio of compression.

192Kb/s: A popular choice for slightly better quality and larger files. 7 - 1 compressionratio.

256Kb/s: Getting close to the upper limit. Sound quality should be virtuallyindistinguishable from the original, unless you are a true audiophile (and if you are, whyare you creating MP3 files anyway?). 5 - 1 compression ratio.

Variable bit-rate

To set the bit-rate for dBpowerAMP audio CD input, select the tracks you wish to createMP3 files from as above, then right-click the 'rip' button to bring up the options window.

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From here you can choose a bit-rate by using the slider.

Variable bit-rate

Most newer MP3 encoding software also offers the option to create VBR (Variable Bit-Rate) files. The idea of VBR is to increase the sound quality of a given file while keepingits size low. This is accomplished by varying the bit-rate used depending on how much is

happening musically in any given portion of a song.

For example, if a song contains long periods of silence or simple, non-overlappingsounds, a lower bit-rate could safely be used in these sections, reducing file size withoutcompromising audio quality. In portions of the song with more audio activity, a higherbit-rate is used to ensure that the detail of the sound is preserved.

Some older MP3 players may have issues with VBR encoded MP3 files. It's worthchecking into this before you purchase.

Most programs that implement VBR include some form of quality setting. This generallyindicates the baseline (lowest) bit-rate that the software will use to encode the song. It

will raise this when necessary, meaning that VBR files will generally be larger than anequivalent MP3 encoded completely at that minimum rate.

DBpowerAMP Audio CD converter does not indicate which bit-rates are used in its VBRsetting. It uses a simple quality vs. size slider. We have gotten good results with this,but experiment to find your preference.

Using VBR in dBpowerAMP Audio CD

Select the tracks you wish to create MP3 files from as above, then right-click the 'rip'button to bring up the options window. Now click 'advanced options.'



Select 'variable bit-rate' and set the desired quality. Hit 'ok' then 'convert' to create yourfile.

How to create audio CDs from mp3 files

If you wish to create a custom audio CD from your newly created MP3 files, the easiest

thing to do is to use CD creation software such as Ahead's Nero, or Roxio Easy CD

Creator. For the purposes of this article, we will use Nero, but the process is similar inother software.

To recreate CD audio files, the software simply uncompresses the files and convertsthem back to audio-CD format. Of course, any quality that was lost in the making of theMP3 file is still lost. The new CD tracks should be acoustically identical to the MP3 filesused in their creation.

Because of this, if you are creating MP3s mostly to make your own mix CDs, it makes

sense to encode them using the highest bit-rate possible. The reason for this is that onceyou burn them both onto an audio CD, a 64Kb/s sampled song takes up exactly as muchspace as a 320Kb/s track, second for second, so you might as well have the better sound

quality that higher bit-rates provide.

To create audio CDs in Nero:

Open the program, select 'audio CD' from the left-hand pane and click'new.'

From the main window, use the file browser pane on the right to locate theMP3 files you wish to use, then drag them into the left-hand pane to addthem to your CD.

The bar across the bottom indicates how much space you have left. The red line can beconsidered the limit.



Once you have finished adding files, go to 'file\write CD...' to open the write window.Ensure that 'finalize CD' is checked, then click 'write' to create your CD.

If you find that you are having difficulty creating a good CD, you might want to try usinglower recording speeds when creating the CD. This can also be accomplished in the'write' window.

Alternatives to MP3

There are several alternative formats available for compressing and encoding CD audio.Microsoft has its own format, WMA (Windows Media Audio), which is probably the secondmost popular (and supported) format for encoding music.

'Ogg Vorbis' is an open source format that originated in Linux, Apple uses the AACformat for its Itunes service, etc., etc. Most of these formats can claim increase qualityat lower bit-rate settings as compared to MP3 files, but none of them (though WMA isgetting close) offer the range of supporting software and hardware players that MP3does.

A vastly increasing range of electronicsare available to playback MP3 files on

your computer system or outside it. Interms of software, the media player builtinto Windows XP (as well as Windows2000 and 9x/ME provided you have

upgraded it from the Microsoft website)has the ability to play MP3 files, andcomes with a variety of featuresdesigned to make the experience moreenjoyable, including visualizations to addvisuals to your music.



Several excellent free third-party applications are around, such as the popular Winamp by Nullsoft.

As for playing MP3 files outside your computer system, there are a variety of choices.While MP3 support in quality home stereo equipment is rare, virtually all home DVDplayers support MP3 playback, and can be easily hooked into your stereo system as youwould for movies.

For portable music, all the major manufacturers including Panasonic and Sony now makeportable CD players which support MP3 playback. As a typical 700MB recordable CD can

easily hold over one hundred MP3 files, this is an excellent option. For an even moreportable option, the small size of MP3 files allows an equally small size of player usingflash memory as the storage device and connecting directly to your computer to addmusic.

Be aware that just because a given audio device advertises MP3 compatibility does notnecessarily mean that it will work perfectly with all of your music. Many older MP3players may not work at all or work well with higher levels of encoding or variable bit-rates, so it's worth looking into this further before you decide what to buy.

Also, many devices which are primarily intended for another purpose, such as DVDplayers, may only work if you place all the MP3 files directly onto the CD, and notorganize them into separate directories of folders.

CD copy protection and Legal issues

(For a more comprehensive coverage of this subject, see PCstats article on LegallyCopying Software and Music )

In the US and Canada, as well as most other parts of the world, consumers are allowedto make copies of music they have purchased, as long as the copies are for personaluse. In other words, you can legally create MP3 files from your CD collection to use in

your MP3 player, or to make a mix CD to play at a party. You cannot, however, sharethe MP3 files with others, or donate the aforementioned mix CD to the host of the partywithout violating copyright. This is fairly simple and straightforward, but if you live in theUS, things are a bit more complicated.

As you might be aware, music companies such as Sony have begun adding copy-

protection schemes to their audio CD releases. Generally, these schemes are designed toprevent the CD from being read or copied by computer CD drives. The companies use anumber of techniques, too many to list here. The common factor of all of them so far is

that there is a way around them, often an easy one. Thing is, under the US DigitalMillennium Copyright Act (DMCA), it is a violation of copyright to duplicate a digitalproduct that has been copy-protected. Essentially, under US law, you may copy musicyou have purchased, unless the owner of the copyright for that music thinks that youshouldn't.... Hmm.

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