The SAS-20 was Korg’s first arranger keyboard. A built-in computer analyzed the melody played on the keyboard, and generated a complex accompaniment. This was the world’s first auto-accompaniment function of this kind added to a keyboard. Also, a more traditional chord recognition system was included.

Korg introduced its first professional arranger in 1993 with the i3 model, which proved to be the first in a huge series of Korg 'interactive' products. Until that time the auto-accompaniment keyboards were designed primarily for home use, but i3 changed that. Its tone generator was an AI2 engine coming from the renowned Korg synths, which made it a perfectly useable 'pro' keyboard. Once again, a Korg keyboard succeeded because of the quality of its factory voicing. It also retained a multitrack MIDI sequencer, Styles and Arrangements that allowed players to use it as a band-in-a-box or compositional tool, improved chord recognition with a big graphical display, a joystick and analog volume controls for each accompaniment section. A new Backing Sequence feature provided also for easy creation of new songs based on styles.

The company introduced the i2, an i3 "on-steroids" with a 76-note keyboard and a new Piano sound.

In 1995 a further improved version of i3 was introduced: the Korg i1, that included an 88-note weighted keyboard, a huge piano sample, and built-in speakers. Other features were similar to the i3, even if new styles were added.

During the same year, other "i-series" instruments with built-in amplification appeared:

The i4S (where "S" stays for "Speakers"). This keyboard was something like an i3 with speakers, but with a smaller feature set.

The i5S was a scaled-down version of the i4S, with a plastic chassis and a reduced set of features. Some new sounds and styles were added.

A module called i5M was also introduced, with specifications similar to the i5S, but with no amplification and, obviously, no keyboard and joystick. This product was really appreciated by accordionists, happy to discover at its heart some added traditional styles and sounds (shared with the i5S).

In 1995, singers also welcomed the "ih Interactive Vocal Harmony", that allowed for creation of vocal harmonizations, starting from chords played live in Style mode, or recorded in a Song's track. This unit is still a best-seller on the second-hand market, thanks to its excellent price/quality ratio.

During 1996, Korg did not introduce any new arranger or related product. However the new Korg Italy R&D department was established in Italy to keep focus mainly over entertainment keyboards. The laboratory actually take place in Osimo, near Ancona, in the center-east part of Italy, an area with strong traditions in musical instruments manufacturing, and was intended to support especially the European market and customers.

The iX300 Interactive Music Workstation was introduced, back to a unit without speakers but offering new sounds and more than 100 styles.

This was the year the first two products from Korg Italy appeared:

iS40 included new sounds (among them, a gorgeous stereo piano sample), new styles (128), and several new features. One of the most appreciated new features, Keyboard Sets, allowed for immediate recalling of keyboard track settings.

iS50 was the low cost version of iS40, lacking just a minor number of features from its bigger sibling.

These two new-entries added to the most important values traditionally associated to the Korg brand name, innovation and great sounds, a reasonable price. Plus, they boasted a completely new, award-winning look.
 

During the same year, the i30 Interactive Music Workstation was introduced, claiming to be the first arranger featuring a Touch Screen Display. This model was speakerless, 64 notes of polyphony, and included some more sounds compared to the iS40.

Korg introduced a successor to the i5M: the i40M module. Specifications were similar to the iS40 (obviously, with no keyboard or joystick), but included a Vocal Harmonizer as standard. Furthermore, the module included 3 different pre-programmed MIDI setups, to make connection with various accordions even easier.

iS35 was a new version of the iS40, featuring the same specifications, and adding a Vocal Harmonizer as standard.

iS50B boasted the same specs as the iS50, but in a Dark Blue chassis.

A new range of arranger from Korg was introduced in year 2000: the Pa Series. Pa80 was the first model introduced in December 2000 with a stunning sound inherited from our award-winning Triton, a wide selection of highly-musical Styles made by some of the best musicians in the world, a Multitasking Operating System and a revolutionary Dual Sequencer design. This new keyboard will bring the benefits of Korg's stunning songwriting and music production/performance to a whole new generation of musicians.
 

The new Pa60 Professional Arranger was introduced. Apart from fewer features like sampling and Harmony Board compatibility, it is same instrument as the "top-of-the-range" Pa80.

During this year, a new line of professional arrangers debuted, starting from the flagship - the Pa1X Pro Professional Arranger. Including some ot the most advanced technologies available in the musical instrument world, it marked the return of Korg to the speakerless, studio-oriented interactive composer type of arrangers. It also marked the beginning of a factive cooperation with the renowed studio gear manufacturer TC-Electronic.
 

Short after the launch of the Pa1X Pro, the Pa1X Professional Arrangers was introduced. This is the speaker-fitted, shorter-scale version of the Pa1X.

After the top-of-the line, ultra-luxury Pa1X Pro, Korg release its most inexpensive arranger ever - the Pa50 Professional Arrangers. Despite the low purchasing price, it boasted most of the same features of the revered Pa60, making it a true bargain.

A successor of the Pa80 with speakers was introduced, named the Pa800. It was a jump forward under the technology point of view: the new Korg tone generator, and the EDS sound synthesis, made their first appearance in this middle-of-line arranger some months before the revolutionary M3 synth line was introduced. Twice the polyphony, physical modeling for guitar effects (based on the REMs technology), track EQ, the new TC-Helicon vocal effects, plus the guitar mode. As usual for Korg, an incremental advance on the surface, yet a ground-breaking innovation in the inner core.

Improving on the almost perfect Pa1X Pro/Elite was a difficult challenge, that Korg faced with the usual, savvy sense of adventure.
The result was the Pa2X Pro: the same solid feel of the predecessor, with an all new and innovative design, and the same sound technology advances introduced in Pa800 just a few months before.
The Double MP3 Player/Recorder (optional in Pa800) was standard, and it was a shock: no more practical differences between SMF files and
MP3 audio files. Slowing down and transposing MP3 files was the ordinary Korg extraordinary. Pa2X Pro clearly aimed at the professional musician, due to its improved 76 keybed, tiltable touch screen, phantom power, balanced in/out, digital audio output and internal clock.

After the renewal of the top-of-the-line model, this year saw a renewal of the entry-level model. After the incredible success of Pa50, the Pa500 made its appearance, considerably improving in the interface design. A modern, stylish case, with a die-hard core - the same of the Pa2X and Pa800 for an incredible price.
This model was made available also in different localizations, to fit any particular musical taste and tradition.

During year 2008, Korg introduced Pa588, a cross-over of an arranger (the acclaimed Pa500) and a digital stage piano, with the 88-note graded-weighted RH3 keyboard, built-in speakers, and a beautiful piano sample. Great on stage, it is supplied with its own piano stand; compatibility with the Pa-Series makes it a perfect home-entertainment machine.

The Pa50SD Professional Arranger loose the old floppy disk in favour of a modern SD Card media.