Arguably, where electronic/electro-acoustic/computer music is "at" right now.
Actually, it may not be arguable, since microsound has never really been pinned down as a genre, like "house" music or "bluegrass". It has some definite characteristics, however.
Microsound is the result of the recent proliferation, explosion even, of accessible digital signal processing (dsp) tools. This, of course, follows hand in hand the explosion of the personal (micro)computer. We have the ability now to interpret and manipulate recorded sound in new and very different ways. Non-linear ways, in particular. Microsound is about artists using using these ways for more than just convenient reproduction of classic studio processes. At least, that's one way of looking at it.
There are as many processes in microsound as there are pieces. Many of them involve manipulating and re-presenting some type of source material. The source can be anything from studio recordings to field recordings to completely artificial synthesis to other artists work. Sound is often sliced into thousands of barely or in-discernible particles using tools like granular synthesis. The particles are resequenced, overlapped, sped up, slowed down, strewn about according to behavioral algorithms, anything you can imagine. Form and texture appear as the density of particles varies, from sparse rhythmic emissions to dense, mutating clouds. It is from this minute, detailed manipulation that microsound gets it's name.
Another area of microsound is so called "glitch" music. Here the source of inspiration are glitches and errors in digital systems themselves. This smacks of postmodern mediation (awareness of the medium). It is also the most popular microsound form. Glitch infused techno, house and "glitch hop" from artist like Kit Clayton, Sutekh, Jetone, Mathias Schaffhäuser, and countless others are finding their way onto trendy dancefloors and lounges everywhere.
Another important characteristic of microsound is it's attitude towards tools. Specifically, the creation of tools in microsound is as important as the creation of the actual music. Or, perhaps more accurately, the creation of tools is a major part of the whole creative process behind microsound. Most microsound artists create their own tools, using audio-specific programming languages and development systems, such as Csound, SuperCollider, and Max/MSP. You could of course simply refer to these systems as their tools, but they are really more like metatools.
For more information you can join the .microsound mailing list at http://microsound.org/
The people and labels listed below are the more pure microsound artists. Some other artists who display microsound tendencies include:
The artists mentioned above, at least two of whom have been featured, not coincidentally, on the Force Inc. Label.
Kid606, in his newer work (PS I Love You) on Mille Plateaux. Mille Plateaux, a affiliate of Force Inc. Music Works, is probably the most important purveyor of the (slightly) more popularized forms of microsound.
Atom Heart. The album Templates from the Flanger project, with Burnt Friedman, is a fantastic example.
More may be added.