can be accomplished using synthesis-modelling of the ADSR envelope or digital modelling (e.g., for the hard strike, the keyboard would add the timbres associated with a hard strike—in the case of a Fender Rhodes voice, this would be a biting, "bark" sound). After-touch: A feature brought in the late 1980s (although synthesizers like the CS-80 extensively used by artists like Vangelis featured after-touch as early as 1977) whereby dynamics are added after the key is hit, allowing the sound to be modulated in some way (such as fade away or return), based upon the amount of pressure applied to the keyboard. For example, in some synth voices, if the key continues to be pressed hard after the initial note has been sounded, the keyboard will add an effect such as vibrato or sustain. After-touch is found on many mid-range and high-range synthesizers, and is an important modulation source on modern keyboards. After-touch is most prevalent in music of the mid to late 1980s, such as the opening string-pad on Cock Robin's When Your Heart Is Weak, which is only possible with the use of after-touch (or one hand on the volume control). After-touch is not normally found on inexpensive, beginner-level home keyboards. Polyphony: In digital music terminology, polyphony refers to the maximum number of notes that can be produced by the sound generator at once. Polyphony allows significantly smoother and more natural transitions between notes. Inexpensive toy electronic keyboards designed for children can usually only play five to ten notes at a time. Many low priced keyboards can perform 24 or 32 notes at a time. More advanced keyboards can perform over 48 notes at a time with 64 or 128 notes being common. Digital pianos, has more complex polyphonic system and could perform by up to 256 notes. Multi-timbre: The ability to play more than one kind of instrument sound at the same time, such as with the Roland MT-32's ability to play up to eight different instruments at once. Split point: The point on a keyboard where the choice of instrument can be split to allow two instruments to be played at once. In the late 1980s it was common to use a MIDI controller to control more than one keyboard from a single device. The MIDI controller had no sound of its own, but was designed for the sole purpose of allowing access to more sound controls