In 1940, a physicist at North Carolina State University named Sidney Wilson built the first-ever fully electric guitar -- with a solid body and individual pickups to overcome strings stepping on one another -- thereby setting the stage to forever change the face of music. In a more conventional sense, it is true that Les Paul 'invented' the fully electric guitar, for he put together the pieces needed to create one which was commercially viable, and over the years he invented and incorporated many features -- such as delay and reverberation -- still in use modernly.

Perhaps the loop station -- which sharply accentuates certain of these innovations -- is not quite so sound-changing of a force, but it is surely a boon, stimulating in recent years the creation of a very particular sound. The theory behind loop stations is simple. The machinery eases on-the-fly recording and playback. You tap a footpedal to catch a sound -- perhaps a few chords on an instrument, perhaps simply a vocalized 'chucka-k-tsst-tsst' -- digitally recording it and instantly looping it and making it the backing track to whatever next sound you introduce by voice or instrument. Sounds can easily be grouped together to be controlled by a single pedal tap, so that by adding successive layers of sound, and then selectively removing and re-adding particular sounds or groups of sounds, a single performer can create a complex and richly textured piece of music, essentially laying down multiple tracks (what would normally require multiple performers) in a single effort. Where multitracking -- another area wherein Les Paul was the great innovator -- allowed a single performer to record and combine all the pieces of a single song, one after the other, a loop station allows all of those pieces to be recorded and laid down at once.

Naturally, this musical innovation has spurred its own unique vocabulary and collection of techniques. The loops themselves are called, well, 'loops' (or sometimes 'phrases'). Much modern music is already known and oft excoriated for its repetitiveness, a situation which loop station aficionados have proved themselves able to evade through surprising combinations of 'pulls' and 'drops.' The machine can be set to start playing the newly recorded backing track on the touch of a pedal, or it may be sound activated to bring that track in when hte next instrument or vocal is introduced. And as with many things musical it is most easy to relate the sound of this piece of equipment and the style it engenders by providing examples. Boss, the maker of the most popular loop station on the market (and one which is surprisingly easy to get rocking on) has initiated an annual international contest, wherein people lay down live performances, and here are some prizewinning performances from that event:
=Phil Stendek - Grand Prize Winner - BOSS Loop Station U.S. National Finals -- One of my faves, and a fine incorporation of Reggea rhythm into the selection

=Naoryu - Grand Prize Winner - BOSS Loop Station Japan National Finals -- my personal favorite

=Matt Mulholland - BOSS Loop Contest 2011 - 'Get The Funk' -- this one is an 'at home performance submission' which won one of the lesser prizes, but it is highly funky; and Matt Mullholland, who normally does straight up multitracks (like this Will Smith medley) or parodies (like this ridiculous angsty cover of Rebecca Black's 'Friday'), proves himself yet again to be an inestimable talent

=Shlomo wins Loop Station World Championship 2011 -- not a favorite of mine actually, but interesting in that this dude uses nothing but beatboxing and voice tricks

=Randolf Arriola BOSS Loop Contest 2011 - With or Without You (U2 cover) -- another at-home submission demonstrating how an existing song with the right sound can be adapted for loop station performance
There are hundreds more such vids posted about, showcasing varying levels of talent and styles, some soft and slow, jazzy or folksy, some acid rock, techno, club, and so on. There is perhaps something for most anyone's taste, but it is all to the taste of those keen on the art of the quick-stepping performance itself.