shorthand/abbreviation for the Roland TB-303 Bassline Synthesizer. Probably the most sought after synthesizer ever, except for maybe the 909. The machine is responsible for an entire genre of electronic music known as Acid (AKA acid house, acid techno).

At first glance, the synth looks less than mediocre. They're small, and usually they aren't in great condition because theyre so old (1982-1983). It was originally designed to sound like an actual bass guitar and replace a bass player in a band, but it didn't really do that too well. The sequencer is a pain to program, and you'd be wasting the rest of the possible sound spectrum if you wanted it to just sound like a bass guitar.

It became popular by using the accent function on certain notes, and tweaking the filter and the accent knob while it plays, creating really squelchy and random sounding effects.

Nowadays, their price can range from around $800 to $1500. There are emulators and clones, but purists say that only a 303 is a 303.
If you own a TB-303 and you aren't into Acid (the music of course) then you have two options. No, you can's use it as a paperweight, although if it is broken you can do that. (who wouldn't want a paperweight that says "computer controlled" on it?)

1. Get yourself a drum machine (909) and start making acid music.

or (and i'd much rather you choose this instead of choice #1)

2. Sell it to me, in which case you can forget about the price range that is listed above, and I'll take it off your hands for $50.
by karl August 11, 2004
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The area code for Denver, Colorado. Sometimes confused with 720, which overlaps it.
by Frank Carter May 31, 2005
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Roland TB-303 Bassline Synthesiser

The best bass synth ever. Period.

Difficult to find an original. Expect to pay $1,000 USD. You can get cheaper software that emulates it.
by someone June 15, 2004
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Roland TB-303 also known as the 'Acid Box' for it is used to make the 'bubbly and squeaky layers' in Acid Techno, Acid Breaks, Acid House etc.
Pete Skank - Stay In Bed Forever is a mind fucking 303 journey.
by Anonymous June 14, 2003
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music group from boulder that has some good songs, but is very overrated (at least in boulder haha)

area code of boulder, colorado, and the beginning of some phone numbers in colorado.
by GTFOOO October 5, 2008
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Machine commonly used in Techno/Acid House in the 80's/90's. Gives crazy basslines
by 303 doo June 7, 2004
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The world's most dangerous bass-line ever. If used in the right way, is capable of smashing one's skull wide open, with brains out on the ceiling. Extremely powerful. Fatal in some cases.
- Pete Skank, 'nuff said!
- W0rd!
by AJ@TA October 6, 2003
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