just wondering ....anyone?

I would say Yamaha around 1980:

Yamaha History
Yamaha PS-2

Kind regards,
Tommy

1978/9
http://www.batesuk.cwc.net/wersi_gallery/instruments/Entertainer.htm

Bill

the earliest form of auto accompaniment was a drum machine built into an organ so that the organist had a percussion section whilst they played . It was roland 1960's

"The first commercially available rhythm machines were included in organs in the late 1960s, and were intended to accompany the organist. The first largely successful drum machine was the Rhythm Ace. It was produced by a company then called Ace Tone (later called Roland). In 1964 it developed the Ace Electronics R1 Rhythm Ace. The R1 was possibly the world's first fully transistorised rhythm machine but, despite interest and sample orders from American manufacturers, it didn't get any wider success."

Yes the history of drum machines and electronic organs is well known and documented, but the early history of arranger keyboards - or portable keyboards as they were called then - is much less known. A reason could be that they were mainly considered toys at that time.

Bill, thanks for the info about the Wersi Entertainer.

Kind regards,
Tommy

Or here:

Sonic State

but neither site is complete and a lot of early models are missing.

Kind regards,
Tommy

http://www.keyboardmuseum.org/ar/k/korg/s/sas20.html


This was one of my earliest Korg arranger KB's....I still have pics playing it on stage from years ago....

It's from 1983. Read more here:

Korg Arranger History

Donny, did it actually do what the brochure says:

A built-in computer analyzes the MELODY you play and adds a complex accompaniment that matches the chord progression.

Kind regards,
Tommy