Retro Hing Hon EK-001 Square Wave Mini Keyboard Synth 90s (not a toy) LOFI Musician

Hing Hon EK-001

main features:

• 37 mini keys
• polyphony 2 notes
• 8 OBS preset sounds {music box, violin, flute, organ, guitar, banjo, horn, piano}
• 8 OBS preset rhythms {disco, ballad, march, swing, pop, waltz, rhumba, tango} with unique percussion; some notes have an accent (no accompaniment)
• 4 drumpad buttons
• tempo +/- buttons (16 steps)
• vibrato button (vibrato modulates the CPU clock)
• master and microphone volume sliders (5 steps)
• sound generation is squarewave based with capacitor envelope; some sounds use multipulse squarewaves (short bit loops). The CPU in turns sends pulse width modulated currents to the capacitor to charge/ discharge it and between them it measures the actual charge voltage to control the output volume by it (using a sample- and- hold circuit?). Exceptional is the "organ" sound, which is an incredible sinister and massive sounding, powerful church organ variant with much reverberation. The piano sound ignores key press duration.
• percussion sounds {base, snare, hihat, cowbell} sound very electronic and extremely impulsive and are best comparable with Atari POKEY chip sounds.
• demo melody "Greensleeves" (2 note polyphonic with rhythm)
• jacks for microphone, headphone & AC- adapter

eastereggs:

• When multiple sound buttons are held down simultaneously, the CPU switches quickly between the selected sounds, resulting in a rough and buzzy kind of fast arpeggiator effect (like known from C64 SID musics). Most of the resulting sounds are relatively disharmonious, but they are unique and sound quite massive. (In unmodified state some of these button combinations mess up the keyboard matrix and though cause undesired side effects like disturbing drum pads etc.)