Specs do not mention anything about the body material. Is it plastic or chipboard or both maybe?

Just curious.

Well, which DP? Many stage pianos and synthesizer/workstations are either plastic or aluminum, while consoles are particle board with a plastic veneer.

Many Yamaha stage pianos and synths have a plastic or metal body with a particle board bottom - which is kind of a downer for me.

Yup; some consoles also have bits of wood here and there (Kawai CA93 has a wooden soundboard, I think?) Higher end ones like the Avantgrand can be made almost entirely of wood..

Same stage pianos have metal frames and cases with bits of plastic, some have more plastic.

Home console style pianos are mostly all particle board with plastic laminate and are typically shipped flat like Ikea does. Some of the laminate is done very well and might use tiny bits of real wood trim.

My Yamaha P155 and others of that line is a compromise between the two and is built on a 5/8 MDF base with a plastic cover.

Actually MDF is a good material. It gives the piano a good solid feel and is sonically "dead". They use metal on the stage pianos because if is lighter and stronger.

Arnoh, as others have suggested, the type of material used for the cabinet really depends on the instruments you are referring to.

With regards to Kawai instruments, portable/stage models such as the ES/MP range typically have a steel or aluminium body with a particle board base. Console models such as the CA/CN range are constructed from wood and particle board. One addition thing to note is that details such as toe blocks/legs are also made from wood, while other manufactures use plastic.

Cheers,
James
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