The Warbo Formant Organ ( 1937 ) , an archetype of today 's polyphonic synthesizer , was a four voice key-assignment keyboard with two formant filters and dynamic envelope controller .
DET PROPN PROPN PROPN ( NUM ) , DET NOUN ADP NOUN PART ADJ NOUN , AUX DET NUM NOUN ADJ NOUN ADP NUM ADJ NOUN CCONJ ADJ NOUN NOUN .