The SP series is not the direct replacement for the PC88 series. The sounds in the SP series are taken directly from the PC88 but its a much lighter keyboard action...hense a much more portable keyboard. The SP series does not have the controller features of the PC88 either. Again its a simple "stage piano" nothing more.
The PC2 series is the next generation of instruments based on the PC88 design. It does have a new weighted action keyboard that we're using in the K2600 series. In addition, ALL of the sounds in the PC2 are new (with only a couple exceptions). It has a new triple strike stereo piano, new stereo strings, new wurlizter and rhodes samples and much much more. It also can be upgraded to 128 voices of polyphony and two 16MB sound ROMs can be added to expanded it to 48MB. In addition it has Kurzweil's KB-3 Organ modeling system and effects processing based on the KDFX engine from the K2500/K2600 series. The PC2 has 6 pedal inputs, a breath controller input and a ribbon controller input. Last but not least the PC2 is the only keyboard on the market with a 24bit digital output. This thing sounds amazing!!!
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