ALPHABET SOUP FOR BREAKFAST
I'm continually amazed at the number of acronyms, new and old, that creep into our speech. It's almost as if we (and perhaps technical folk of all stripes) have our own little sub-language. If we drop enough of these in to our everyday speech, we become incomprehensible to all but those that share our vocation. Maybe even to them, too. Does this make us seem more mystical and important?
So here's a glossary of some of the ones I've been thinking about. This is a game we can all play, and I'm sure you'll think of a whole bunch that I've missed. Maybe we can even print up a codebook, er I mean a handbook, so that others can follow along. Or maybe not. I wouldn't want to ruin the mystique.
HD Radio is the new name for IBOC (In-Band On-Channel, or alternatively, It Bothers Other Channels) in the States. Same stuff, new name. Hey, people, it's called marketing. We don't know what the "HD" stands for, but its developer, Ibiquity, has gone on record to assert that it most definitely is not an abbreviation for "High Definition." Of course not. Who would be silly enough to think that, except perhaps the general public?
The AM version of HD
Radio has so far been restricted to daytime-only, since at night it causes
undesirable interference, but there are forces Stateside lobbying hard to just
ignore all that and press on 24/7. And
they just might do that. This could be
the end of AM radio in
Tomorrow Radio is a scheme originating with NPR (National Public Radio), also in the States, to allow FM stations carrying HD Radio to carry two stereo programs on their digital selves. The primary would be simulcast on the analog side, the secondary program would be a whole new, unrelated program, sort of like two stations for the price of one. Think digital, stereo SCA, and you get the idea. It might also be a plot to get the bitrate of FM HD Radio down to parity with AM HD Radio, so all HD stations will have equal quality audio. But not good quality audio. There's only so much you can do with 30 kb/s or so.
Some other folks, led by Axia, want to use the extra channels for a broadcast format for surround sound, apparently figuring that four or five channels of so-so quality are better than two of fairly good quality.
MP3 is the destructive audio-crunching algorithm developed by Fraunhoffer that allows music files to become small enough to be internet-friendly. These days, Fraunhoffer spends most of its time in court, trying to catch people who have been using their algorithm for commercial purposes without paying the piper.
AAC, with or without a "+", a.k.a. HEAAC (High Efficiency AAC) is a newer technique, for really constrained audio formats, and it may or may not be at the audio core of HD Radio. Ibiquity isn't telling, even though they promised the FCC that they would, and it seems that no one can make them. It is used for internet audio streaming, and my Apple iPod really wants permission to convert all my Windows Media files into this format. It frequently reminds me that I should want this, too.
DRM usually stands for Digital Radio Mondale, which is an alternative digital format that is being used a lot for shortwave transmission. Sort of like IBOC, but without the analog simulcast, or the costly Ibiquity licensing.
Dolby 5.1 is a DSP-induced mystical way for making surround sound happen. If you thought it meant five audio channels, one of them a common subwoofer, well I understand where you're coming from. If you've been in an audio superstore lately, it would seem that the number of channels just keeps on growing … already up to seven or eight. No idea where this will end.
DVB, or Digital
Video Broadcasting, is an MPEG-y, COFDM-type way to transmit digital
Clear as mud? Then make up some of your own!