In 2003, the expanded version of K-Station was released. Updates introduced in Novation KS4 concerned the keyboard which got the octaves increased up to 4 (49 keys), some additional features and advantages. A semi-weighted keyboard acquired aftertouch, each of the 33 knobs and sliders send MIDI information. KS4 offers a 4-part multitimbrality with 4 separate assignable outputs. A very useful feature is the section with independent effects for each part, a unique feature taken from Supernova.

The instrument includes 8 voices of analog modeling sounds with FM, vocoder, arpeggiator, reverb, delay and 400 user programs. K-Station has 3 oscillators generating sawtooth, triangular, sine, and triangular with PWM waveforms.
The nit even has a basic FM for the synthesis of more "aggressive" timbres. All oscillator settings can be altered owing to unison, hard sync, or addition of some noise to standard waves.

K-Station has a built-in low-pass resonant filter with switchable modes of 12/24 dB, and envelopes: attack, decay, sustain, release (ADSR). Additional envelopes interact with the oscillators, and with LFO. Among the built-in effects you can find reverb, delay, chorus, phaser, flanger.

Their sends can be controlled with the modulation wheel. The 12-band vocoder is included into the effects section, it is responsible for processing external mono sounds, such as a cappella and drum loops. External sounds can also be used as a generating source, pass through filters, envelopes, etc.

In addition to the above mentioned effects, the synthesizer has a built-in arpeggiator. Most notably, K-Station has a compact keyboard that is very pleasant for playing basses, leads, pads, and many more. The synthesizer was used by the famous duo, creating in the genre of psy trance - Infected Mushroom.