Friday, December 10, 2004

HiFi #1

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WebRadio: A Huge Source of Music
by Dan Shanefield

Most readers probably know about receiving music via "streaming" on the internet --- in other words, via "WebRadio." However, in case anyone is stuck with just a single web address (URL) and is tired of the music that's available there, here are some more ideas, in addition to some general information.

There are far more "stations" on the web than the 100 or so available by satellite radio. You can listen to many of them free of charge, and you don't have to be near the transmitter --- the signal is equally loud whether you are a mile away or on the other side of the world, as long as you have an internet connection. With some telephone wire modems, you might have a modem speed that is too low, but any DSL or cable modem connection should be OK.

One thing that you will need is a "player" program, running in your computer. A popular player is RealOne, which you could download into your computer from www.real.com, and another can be obtained from www.WindowsMedia.com. You can get iTunes and QuickTime from Apple, free of charge (search for them on google and click on them, even if you use Windows). Now most other player programs require a small monthly or yearly payment, although they do offer additional features besides just the use of web radio streaming (one example being MP3 decompression).

Why do you need a player program, and what is streaming, anyhow? Well, first of all, the transmission medium, that is, the internet, is all digital, and somehow this has to be converted to analog before it gets to your loudspeakers. (If anyone wants to see an explanation of digital versus analog, and the advantages versus disadvantages of each, they could look briefly at pages 209 - 213 in my book, "Industrial Electronics...etc..." available from amazon.com. Also, we could never do all this in a practical way without integrated circuits, which are explained on pages 249 and 257 of the book, but most LC readers probably know that stuff already.)

An ordinary D-A converter can't play continuous music over the web, because the internet does not use a 16-bit "word" coming right after another one, in a continuous sequence like a CD player does. Instead, the signals are broken down into clusters of various lengths called "packets," and they go along whatever pathway happens to be not busy at a given moment. These are temporarily stored, and they get put back together in the original sequence later on.

"Streaming media" involve special types of packets which are compressed in order to use fewer bits, something like MP3 does, but using its own proprietary system. If you really want to know more about this, download a free copy of U.S. Patent 5,132,992 from www.uspto.gov . (However, don't bother unless you have plenty of time for your brain to decode and decompress this patent, which is not clearly written!) By the way, Acacia Research, who owns the patent, is now proceeding to sue dozens of big companies like Microsoft, Sony, Disney, etc., for using streaming without paying royalties on that patent (maybe hundreds of companies in the future!). You're bound to hear more about this in the news, and it might be fun to notice what happens here. Side Note: In the current (June 2004) issue of the IEEE magazine Spectrum, on pages 38 thru 43, there is an interesting article about the first skirmishes of this legal battle, which covers U.S. Patent 5,132,992. The IEEE article is visible at website
http://www.spectrum.ieee.org/WEBONLY/publicfeature/jun04/0604aca.html .

The streaming media methods, of which there are several variations, are also used for telephone transmissions via the web ("Voice Over Internet Protocol"). Special coding can also be added, to keep you from decoding it if you don't pay a fee. A more powerful compression and coding scheme, MPEG-4, is used for sending television via the web, and more and more lately for short news clips and ads, porn shows, and continuous web-camera video transmissions.

Another thing that is needed for music via web radio is a sound card in your computer, and some kind of loudspeakers, built-in or external. When your computer is logged on at your web server, and you write the web address of a station (like www.wwfm.org , which is one of my favorites for classical music), you might then have to click on a "Play Radio" icon, and then on an icon that identifies what kind of player program you have (like iTunes). However, some or all of this can happen automatically, once you "go to" the station's website (which is the case with iTunes). Sometimes it is not at all obvious, as often happens with computers, and you have to hack around a bit (like hitting the "START," then "PAUSE," and then "START" symbols) before you suddenly hear music.

On some occasions the music will stop for a minute and a "refresh" symbol will appear on the screen, while the decoder catches up with your player. This could be caused by your assigning "small" memory to your player program instead of "large" (if you know how to choose that), or by your selecting too high a bit rate (like 128 kbps, where 32 kbps would really sound OK), or just by bad luck (too much other traffic on the internet in the evening). If you don't want to bother booting up a computer just for web music, you can feed your internet connection into a little box obtainable from www.rokulabs.com , and then feed the Roku's output into your stereo amplifier and speakers, bypassing the computer.

Did I hear you say you want a lot of variety? Try a search in google for webradio and also web radio (with a space between the words). You'll get about 8 million responses, many of which are internet radio stations from around the whole world! The commercial classical music stations like www.wqxr.com in New York City tend to have irritating ads in the audio channels (I wouldn't mind if they were just on the screen, but they're too loud on my speakers!). Many European governments have no-advertisement music, but the announcements about the the composer, etc., are not in English, like from Sweden on www.sr.se/p2/srk/ . A good one from Canada, with popular as well as classical music (and news, etc.) is www.cbc.ca, which has unique programs around Christmas, Easter, etc. I live too far away from the border to get CBC over the air, but it's fine via the web. (Thanks to Joe Prahler for telling me about that one, just before Easter.) Many government stations carry interesting ethnic music (such as Celtic dances on CBC, etc.).

Some of the stations require you to pay a monthly or yearly fee, just like some player programs do, although the government stations usually do not. Overall, one of my favorites is www.classicalmusicamerica.com/ . (This used to be called ClassicalMusicDetroit. It doesn't play any ultramodern dissonant music, but it does have a few ads.) Another good one is www.magnatune.com , which is free if you are using the iTunes player, although you might have to pay something with other players. (Magnatune generally plays the most famous classics, plus a few very old motets and Gregorian chants.) For Jazz, my favorite is www.smoothjazz.com (although if you like more bite in jazz, your impression might be that it's just mushy "elevator music"). Some broad-base stations offer amazingly wide ranges of music via specialized sub-group connections. A couple of good ones are www.live365.com and www.comfm.com . A useful guide to the world's English language noncommercial stations is at http://www.publicradiofan.com/ . Anyhow, if you don't find what you like at any of those, you've got about a million other choices, via google.

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Classic Cat
by Dan Shanefield

Another way to get music via your computer (including a tremendous amount of jazz, and also classical, etc.) is to download each song and save it, and then play it whenever you want to. A huge website for this is http://www.classiccat.net/ , or any of the various sites that are linked to it. Much of the music can be obtained free of charge, but roughly half seems to require a sign-up process, complete with a credit card number and an e-mail address. You would need a "player" such as RealOne or Quick Time. (The latter will work with the Macintosh operating systems 8, 9, 10.2, or 10.3, but not with 10.0 or 10.1.) Apple Computer is now making current rock music (and quite a lot of jazz and pre-rock pop) downloadable for 99 cents per song, and a few other companies have recently gotten into the act also. However, as far as I know at this point in time, there is very little downloadable music available that's classical and also free, outside of classiccat and its links, except for some easy-listening variations.

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