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Re: OT ... audio

Jim wrote:
> I guess this is OT unless someone out there is installing audio
> video.
> I regularly install home theater systems for my clients. Install flat
> screens, surround speakers, receivers and integrate all their hardware
> and teach them how to use it.
> Every once in awhile someone asks me about MP3 players and downloading
> music, which I personally, have never had the desire to do. What
> little I've heard of it ..... it sounds like pretty poor quality
> audio ... to me. But, I guess some people just want the music,
> regardless of what it sounds like.
> Anyone out there know about or can direct me to some of the basics
> about downloading, use and installation of MP3(?)
> ...... "stuff" ? Is there anything other than MP3?
> And ...... are there "better" sounding music downloads? Better
> computer recording programs/applications? Better players ..... etc,
> available?
> Just need a little handle on the basics.

Well first of all, the main factor in MP3 quality is the level of
compression - the more compression, the smaller the file, but the lower
the quality.  Typically you'll see MP3s listed with a "bitrate" -
128kbit is generally considered to be the lowest acceptable for decent
music reproduction and provides approximately 10:1 compression; 320kbit
is usually about the highest you'll see on downloaded material and
reduces the ratio to about 5:1 (exact compression ratio will vary with
the material).

Quality can also be somewhat affected by the codec
(compressor/decompressor) used to create the file, and to a smaller
degree by the codec used to play it back.

The player itself is pretty much a non-factor except where it may add
other effects or processing to the playback.

There are better-sounding compression formats... WMA (Windows Media
Audio) can often be "cleaner" while allowing lower bitrates (and thus
smaller files); FLAC (Free Lossless Audio Codec) is another common codec
that in theory at least causes no loss of quality, but generally only
compresses by about 2:1.  If you're jamming stuff onto a portable player
or "ripping" CDs to hard disk, you can also just rip straight to
uncompressed WAV format, with no quality loss but no space reduction either.

As to why... when you figure that CD-quality audio, at 44.1kHz, 16-bit,
two-channel sampling, requires 176,400 bytes *per second*, or just over
10MB per minute (not including overhead), a 10:1 space savings can be
substantial, which was the original attraction of MP3 in the days when
just about everyone was still using dialup.  A full 640MB/72-minute CD
can be reduced to <60MB; 10 CDs' worth of music can be fit on a single
CD-R, or upward of 65-70 full albums on a DVD-R.

As far as installing playback devices, well, it really depends on the
type of device.  If you're plugging in a portable, most can just use a
standard 1/8"-stereo-headphone-plug-to-RCA adapter cable plugged into a
stereo line input on the receiver.  Some receivers now have a 1/8" input
jack in the front to allow easy plugin of portable players.  There are a
few "component" playback units out there, but they're rare, since they
generally don't provide any better quality or functionality than their
portable cousins, without the benefit of being portable.

More popular are streaming-media receivers that will connect to your
home network (usually via wireless) and pull music and video files off
your PC or a media server.  Some also have the capability to connect to
streaming "internet radio" stations.  These are generally designed to
not be portable, and to integrate better aesthetically with a home system.

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