- 2006.04.11
Back to business with our audio
jukebox project. This week we'll examine the applications that
allow us to get music onto our Macs. While there are more
applications than the ones I'm covering today, not all are still
available for download. If you happen to have a copy of SoundJam,
MacAmp, or other long abandoned encoder, please feel free to use
them if preferred.
Most people will want to bring digital music onto their Macs in
one of two sources - ripping from CD or downloading from the
Internet. Ripping from CD requires you to choose the quality of
audio desired for the encoding process.
Lossless Encoding
At the top end are the lossless codecs that create big files
while allowing for full CD quality audio. AIFF and WAV are the most
common formats and simply represent a direct copy of a CD's data to
your Mac.
There is not much difference between WAV and AIFF, and for all
intents and purposes they are interchangeable. Macs tend to
recognize the audio data as an AIFF file and Windows sees the same
data as WAV. Technically, AIFF and WAV are not lossless compression
schemes, as they don't actually compress the audio data. These
formats do represent a lossless copy of the original file, and I
desired a simple way of grouping the different audio formats.
Other popular lossless formats are Apple Lossless, WMA Lossless,
and the open source FLAC
(my favorite). Unfortunately, as far as I can tell, none are
available on the classic Mac OS.
Again, while AIFF and WAV are lossless codecs in the sense no
quality is loss from encoding, these two formats don't give any
advantage in file size. FLAC, Apple Lossless, and WMA Lossless all
allow for some compression, but retain full quality. Typically,
file size is reduced by half with these true lossless codecs.
Lossy Encoding
On the opposite end of the encoding spectrum are the lossy
codecs. The lossy formats applicable to this article, Ogg Vorbis
and MP3, are characterized by greatly reduced file sizes and a
corresponding loss in quality. These lossy codecs are measured
primarily by their bit rate (kbps). The lower the bit rate, the
smaller the file size, and the lower the audio quality.
Another technique for encoding is to select variable bit rate
(VBR) encoding. By choosing VBR, the encoder is able to select a
bit rate that varies on the fly depending on the quality needed by
each segment of the audio track. The listed bit rate is an average
of the track's continuously variable rate. While a song may be
listed as 256kbps, any single passage of the song may be rated much
lower or higher.
Overall VBR seems to be a welcome refinement of the lossy MP3
and Ogg Vorbis formats. There are further refinements available
such as choosing between mono or stereo. Typically music will be
encoded in stereo and spoken word sessions (such as a podcasts) can
get away with a mono encoding.
Decisions
The most applicable encoding will depend on the specific goals
of your project. The most important concern is typically storage
capacity. If you have a Mac with a large hard drive, either
internal or external, you can use the higher quality encoding.
Depending on the size of your CD collection and available
storage capacity, one goal could be to make exact duplicates of an
entire CD collection. Simply import the audio from the CDs as
AIFF.
AIFF files can be played back on a wide range of computers and
should be compatible with 68k Macs as well as PPC Macs. AIFF
encoding is a very straight forward process. Simply select the AIFF
encoder in your application of choice and begin. After all, an AIFF
is simply a full copy - in both size and quality - of the audio
from the CD.
If disk space is limited or particular listening needs entail
cheap earbuds or computer speakers, lossy formats may be preferred.
My rule of thumb is 128kbps VBR MP3 or Ogg Vorbis is the minimum
acceptable. 128kbps constant bit rate is okay. Preferably I get
much closer to 256kbps VBR MP3 and Ogg Vorbis.
How does one get music from a CD onto a Mac? Quite simple
really. Start by firing up your designated Mac jukebox, place a CD
in its optical drive, and select one of the following applications.
Directions and options will differ depending on which application
is chosen.
Audion 3.0.2
Audion 3.0.2 is the most
flexible and robust of the currently available choices. Encoding
CDs can be accomplished with the included MP3, MP3 LAME (despite
the name, LAME is a great encoder), mp3Pro, and AIFF encoders.
While Ogg Vorbis encoding support is missing, there is support for
Ogg Vorbis playback.
I'm not sure which MP3 encoder is best in a technical sense, but
I tend to use the LAME encoder.
The mp3Pro encoder deserves a quick note. In theory, mp3Pro will
give you twice the quality of MP3 at the same bit rate. While the
only application to take advantage of the format under the classic
Mac OS is Audion 3, mp3Pro encoded tracks are compatible with other
players. Under non-Audion 3 players, mp3Pro encoded files will play
back as a normal MP3 without the increased sound quality available
from mp3Pro. Unfortunately, mp3Pro never really caught on as a
format, so I tend to stick with normally encoded MP3s.
When you use Audion 3 to encode (or rip) your CDs, I suggest
connecting to the CDDB in order to automate the process of labeling
artist, track name, album name, and genre. The CDDB is a repository
for all the audio CDs people have previously labeled and uploaded
the database.
Sometimes there are multiple entries into the CDDB for the same
album. The Audion preferences can be set to automatically select
the first choice or to present a list of choices. While the CDDB
sometimes contains mistakes, I find the occasional manual nip and
tuck of the results is a small price to pay for the time saved by
CDDB doing most of the work. When importing your encoded music,
Audion can create Artist folders and Album sub folders within
designated output folder.
Automation
Audion's tricks for streamlining the process of importing music
from audio CDs is only beginning. While a tad buggy for me, I found
the ability to do batch importing handy. If you have a fair share
of CDs to import, having to insert each CD and then manually
selecting import can be a little tedious.
Once an encoding scheme has been selected, the batch process
will prompt you to insert the first CD, and once the CD is finished
encoding, Audion will automatically prompt you for a second CD by
ejecting the first disc. Upon inserting the second CD, the process
automatically begins again, until this CD has been encoded and is
subsequently ejected.
This process will continue for as many CDs as you need to
encode. The only real drawback to the batch encoding process is
that every track from the CD will be encoded. If not all audio
tracks are desired from a groups of CDs, then the batch process may
be less of a time saver.
Labeling ID3 information continues to be very easy, even after
encoding. Indeed Audion allows the ability to select multiple
tracks when editing, which makes listing artist, genre, and album
details much less tedious. If you like to tweak the actual audio
file, Audion even has an MP3 editor with a few included
effects.
iTunes 2.0.4
iTunes 2.0.4 is very similar to Audion 3.0.2, but it has far
fewer features. Unfortunately, the choice of encoders is limited to
two, MP3 (no LAME encoder option) and AIFF. The CDDB identification
process works equally well, and creating artist/album folders is
just as automated. iTunes 2.0.4 does not have a nifty batch
encoding option, manually editing ID3 tags is not as slick, and it
certainly lacks the options for customizing MP3s.
iTunes 2.0.4 is not a bad application, just limited in
comparison to Audion 3.0.2.
Ogg Drop
Ogg Drop is the only currently available application for the
classic Mac OS that encodes Ogg Vorbis tracks. It's a very basic
application.
Once the encoding scheme is chosen, Ogg Drop will grind to a
halt if an attempt is made to directly access a CD. It's better to
use Audion or iTunes to identify the CD and then import as AIFF.
Once you have an AIFF file, simply drag and drop onto the Ogg Drop
Encode List window.
Adjusting ID3 tags is simple with the included ID3 tag editor.
There are managed bit rate options, but the developer suggests to
use the VBR option. Everything works well, if a tad slower than
encoding MP3s.
Next time we'll explore the methods for discovering and
downloading music online. I will examine the applications needed,
the websites to visit, and deviate a bit by discussing the
ramifications of DRM and a possible future solution to the
non-interoperable DRM from separate digital music vendors. (No, I'm
not specifically referencing the
proposed French law or the obvious decision to not purchase DRM
infected music.)
