The instrument
The Yamaha Portasound PS and PSS electronic keyboards were produced in the 1980s and 1990s as a low-cost alternative. The name Portasound refers to the portability of the instruments, which all run on batteries. The PortaSound synthesisers were mainly designed for children and beginners and often had small buttons and simple preset functions suitable for teaching. In 1982, a card-reading system was introduced that allowed players to learn and play along with sequenced songs. The PS-55, on the other hand, is a higher-end keyboard with advanced features.
Details
The PS-55 has a rhythm generator with digitally sampled drum sounds, a sequencer/recording function and a C-to-C keyboard with four octaves. It has two stereo loudspeakers with a maximum output power of 5 W (impedance 6 Ohm). The solo voices section contains 16 monophonic sounds that can be combined, as well as the three effects vibrato depth, sustain and celeste. The voices in the orchestra section are fully polyphonic. The rhythm machine offers 16 preset rhythms (each with five different fill-in variations), which are based on PCM-sampled drum sounds. The music programmer can record sounds with up to 800 notes. The first one and a half octaves of the 55-note keyboard form the auto-bass chord section. There are also single-finger chords, arpeggiator and duet functions, which add a two- or three-note harmony to notes played on the right hand (melody). (Source: muzines)