sorry some members here most understand what is a computer at fist:

A computer is a machine that manipulates data according to a set of instructions.
http://en.wikipedia.org/wiki/Computer

a closed arranger system is a computer to.
only differents is you have sounds burned on flash chip that can be done by factory. some soundcards on PC have this to, the MS have this to. but closed system are very slow for sampling becouse of de hardware used in a closed system. you have samplers like AKAI S6000, they are computers to but.i have used AKAi S6000. Akai S6000 has many options but is limited in view of today's PC.

Most people think they have the same PCs as 6 years ago, while many in the field of hardware and software is done and continues to happen.

only the big 3 keep fooling people with rycling of old hardware and chips
but now have become computer parts very cheap and is time for open system like MS from lionstracs