Personally, IMHO, there is quite a difference between a synthesizer and a workstation.
To me a workstation is a unit that allows you to produce songs. They generally have a way to save song data, normally this is through a midi sequencer, but some of the really powerful ones now allow you to record audio to disk and some even burn CD's. But what they generall all have in common is a vast array of sounds, from drum kits, to acoustic instruments to techno, they almost all have a good appregiator. Most have synthesis abilities in them.
Now a synthsizer is really a unit that allows you to created and edit and store the sounds themselves. This is mostly done nowadays buy starting the sound creation process by using a sampled waveform. Then filters, amplifiers, effects are all placed on top of the wave form resulting a "patch" or "voice". It is possible to layer waveforms too.
Now there are also "performance synths", which are synthesizers with added features to allow you to use it more productively live. If a synth can layer and change patches and even act as a midi controller for other synths... it's more in line with a "performance synth".
So a workstation is generally a synth with the extra ability to produce songs. Many features of a workstation can simply be used live and not for producing music, such a you can trigger a sequence live, or use the arpegiator live....
There is a keyboard out called a Kurzwiel PC2 (and probably others, but I'm aware of the PC2). It's not a synth. You can not create and edit patches. You can however add and save effects to a patch.. so from that perspective it's technically not a synth. As are many persoanl keyboards and some arrangers, not synths.
That's my understanding... now what's better to get? I guess it's up to you. You'd have to consider what you need and how much you can afford.
Peace
Bob
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