Hello!
Getting that PSR or any arranger keyboard (anything with built-in speakers and programmable accompaniment) is not such a bad idea.
It will give you a lot of different sounds and features to play with without making things overly complicated.
So if you decide to do that feel free to post at the General Arranger section. Actually post there in any case. There’s a lot more traffic there as well as people who won’t mind explaining you the basics about MIDi and MIDI sequencing as wel as Audio recording and software.

If you decide to go more electronic and get something more advanced than perhaps getting a beginner level workstation like a Korg Triton LE or a Roland JUNO-D is the way to go.
You will however need at least basic understanding of MIDI, some external speakers (a Hi-Fi will do) and some sequencing software too. Oh yeah, and a midi interface.

And finally to answer your question about Moby. He uses more equipment than I can list on this page. Such is the case with all the other artists and producers. Just to give you an idea (I have a relatively small studio) I have four keyboards, five modules and ton of ssoftware. I downsized because I switched to using software synths. Before that my studio looked like a music store.


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