Elka Concorde X-902 weirdest organ synthesizer vintage

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via this auction

Top: "2 x Red - Start, Key, 2 x Grey - (BASS SELECTOR) - Auto, Bass, Walking Bass, 5 x Grey + 1 x Red (BASS) - Rhythm, Bass, Bass Guitar, Bass Sustain, Memory, 3 x Yellow + 1 x Red (ACCOMPANIMENT) - Piano, Guitar, Brass, Memory, 5 x Grey + 6 x Red (RHYTHMS) - Tango, March, Waltz, Slow Rock, Swing, Rhythm & Blues, Jazz Rock, Shake, Boggie Woogie, Afro, Beguine, Samba, Mambo, Rhumba, Cha Cha, Bossa Nova

Left: "Top Row: (SUSTAIN) - Bass, Chords (Strings Chorus, Piano Clav., Flutes), Treble (Strings Chorus, Piano Clav., Flutes)
Bottom Row: (VOLUME) - Bass, Chords (Strings Chorus, Piano Clav., Brass Presets), Treble (Strings Chorus, Piano Clav., Brass Presets)"

Tabs: "1st Set (9): 2 x Grey - Flute 16', Flute 8', 1 x Light Green - Piano, 3 x Dark Green - Cello, Strings Chorus, Memory, 2 x Light Green - Piano, Clavichord, 1 x Red - Flute Cancel"

via Combo Organ Heaven where you'll find additional details and pics.