MP3 - A Player's Guide...
The concept of a streamable, reasonably hi-fi medium of distributing audio is
a boon for listeners and musicians alike but don't be fooled by the hype...
mp3 is lower quality than CD and CD is thought to be not good enough by some
What is mp3?
mp3 is the file format for the MPEG-2 level 3 codec (compression/decompression
algorithm) which strips information that is thought to be redundant
(out of band frequency responce) in order to achieve file size reductions
over CD of something approaching a twelfth. The actual method is more complex
than just just chopping frequency responce and entails frequency band slicing,
and then some chopping according to some rules about the relative perceptual
importance of the various frequency bands.
For example, one minute of stereo CD quality sound at 44.1kHz will require
about 10Mb of storage space.
Encoding into the mp3 format would reduce the space to under 1Mb.
Let's look at some issues.
A Rallying Point
mp3 has become a rallying point for disparate groups -
people who don't like Big Music; people that like the elegance of music
delivery without moving parts (in a Rio anyway); people who want to be
the next Big Music; people who make music.
People who make music like the format because it enables them to
distribute high fidelity music without having to use
expensive specialised studio equipment - they can do it on their own
computers. This in turn has led to a huge quantity of new music
being made available on the Web. It also led to the distribution
of the products of Big Music...
Various statements have been made by record companies or their reps
about the money they are loosing or are likely to loose.
The figures are mostly guesswork of course. A little like Microsoft's figures
for pirated software in China...
The point is that very few of those people could afford Microsoft products.
They either use them for free or not at all ... which is an intro to the kids.
mp3 collector's aren't necessarily poor but a lot of them are kids and in
the early days at least, many of them were just building enormous collections
of pirated mp3s because it was fun - a little like baseball cards but a bit
more interesting because the activity was supposed to be "bad". The kids
couldn't exactly see how it was bad because when they took something the
person they took it from still had it. They didn't have the money to pay
for them so the person hadn't lost any money either. Did the record
companies loose from this? Probably. But not very much. Another category
of collector is the "warez" dude (which is quite often the same category
we've just been talking about) who will have pirated software and music up on
ftp and the web. Would the people that swapped photoshop for five top 10 mp3s
have actually bought them?
In any case the latest moves by the big record companies have been
towards developing other codecs for downloadable music that, together
with hardware support will only allow limited copying. They tried to
do a similar thing a few years ago to cut down on cassette copying.
It'll be interesting to see where they end up.
What about ordinary adults? The people I know fall into two main classes.
The first only use computers under sufferance if at all and wouldn't dream of
putting or playing music on them. So they're pretty much out of the discussion
except as far as their habits might change in the future.
The others use mp3 as they once used cassettes. They buy music, copy it
to mp3, and listen to the mp3s on their computers or on Rio's while being
out and about. For serious listening or party time the CD or record
gets played on the stereo. The main problem for record companies with
all these people is to have something they'd actually care to buy.
PROBLEMS - Storage and Quality
If you ask the latter group about whether they'd consider just having mp3s,
they'll site three problems - quality, storage and the absence of covers
to scan and the small rituals of "putting on" a piece of music. These problems
don't threaten mp3 as a valid sound format but they do threaten it as being
the next big thing in music distribution.
Storage first - How many people right now would entrust their music collections
to a hard disk? Some future gazers have already said that with the fat
bandwidth pipes of the future people might just download music as they need or
want it from central servers - zip, it's done. Problems of backup would be
tackled by the server farm. That would handle the storage problem but not the
behavioral one. Admittedly, new behavours might develop with a new delivery
system and these might be spurred on by new features such as video intros
and new and unusual track listings (a different sort of cover). Music has been
around in human society for a long time so it's hard to believe that it'll
actually combine with or morph into something completely technology based.
Right now storage is percieved as a problem where mp3s cost money.
Quality - Aha, a real can of worms! There is a sizeable group of people who
always thought the "red-book" standard for CD wasn't good enough. The sampling
rate is too low, they say, and the resulting bandwidth too small. One theory
is that we only get meaningful information from somewhere between 20Hz and
20kHz ("red-book" CD is consistent with that). Another is that the band width
is actually much wider and that psycho-accoustic studies haven't yet
identified exactly how wide the band is or how it works.
Unfortunately this group includes some fairly looney audiophiles who will sell
you amazing cables (amongst many, many other things) which would have to defy
the laws of physics to work. It also includes practical and renowned
engineers such as console designer Rupert Neve who believes in a bandwidth of
a 100kHz. More recent adherents to the doctrine of increased bandwidth are
Matsushita with their DVD and Sony and Phillips with SA-CD.
What we are talking about here, in the outer limits of bandwidth is
harmonics - nuances of sound and feeling.
An interesting sideline is provided by John Watkinson (a 20-20k man). In
the Aug '99 issue of Studio Sound. He comments "The widespread adoption
of lossy audio compression is partly due to listening tests which were
carried out on inadequate loudspeakers ... I have found a way (of testing
the bit rate of speakers) and the measured results on typical loudspeakers
are appalling at about one tenth the bit rate of a CD. No wonder lossy
compression can't be heard with speakers as bad as that."
The truncated bandwidth makes no difference on some forms of pop music but
classical music will loose some of it's sheen. You would need to have top
quality components in your stereo to notice though.
No crystal ball here but music distributed on physical media will have
higher bandwidths than the current CD format. Bandwidth will increase
but fairly slowly in the short term (if you are rich you can stream
CD quality or higher right now).
The mp3 codec will be around for quite a while. It may not play much
"commercial" music in the near future but there will be a huge
assortment of amateur music to choose from.
Data Rate Sounds like Channels
8bps telephone mono
32kbps AM radio mono
64kbps FM radio stereo
96kbps near CD stereo
128kbps CD (red-book) stereo
256kbps studio stereo
from Fraunhofer-IIS via Studio Sound
Eric Sheirer has a concise FAQ about mp3
(MPEG-2 level 3) and MPEG-4
mp3 - music
mp3 - search
mp3 - players
RealJukeboxXwindows and Windows
More players for Linux
mp3 - players