I just want to know is there any difference between Piano and Keyboard's/Synth's basic music theory. I mean what if someone is well versed in Keyboard/Synth can he be able to play piano with ease?

I'm not sure, about this, but the opposite is true.

For maximum flame output, you should pose this question on the Pianist Corner forum ;-0

Music theory is music theory.

If you are well versed in theory and keyboard technique you can move to piano with *relative* ease. By this I mean you will be able to play whatever you can play now, but very badly. You will stumble over the black keys which stick up higher, some notes won't sound, others will boom uncontrollably, especially the black keys. At least, that was my experience, going from an unweighted keyboard to a digital piano. If you're prepared to suck for a while, yeah, it's easy.

The big thing about synth is waveform theory. There's a million different ways to produce sounds from a good analog synth, which is why synth artists spend so much time crafting sounds. Piano theory would ignore this part, since piano only produces one sound, the one of hammers hitting steel strings.

I think someone who is well versed in synth will miss features like after touch, but as long as that player was using weighted keys, I don't see why they would have too much difficulty going back to a piano.

The feel of the keys is very different. It will take time before you adjust to just how hard to have to play. Pianos require much more force.

Also the musical genre is different. But even in the same genre, I think a piano would play different notes and cords

I'm not sure what you mean here Chris - would you elucidate please?

Music theory is the same for a keyboard as it is for a piano. All of the chords and scales are identical.

Because of the language difference it's possible the OP was just asking about being able to switch easily between different kinds of keyboards.

If that's the case, it would be difficult for me to switch from weighted piano keyboard action to an unweighted synth action. I'm sure I would eventually adjust though I wouldn't like it - it would be a step down.

Traveling in the other direction would be much easier I think.

I've stated this several times. I sat in with a combo a few years ago where their keyboard player used an unweighted keyboard. I must have played at least 15 minutes and I never got the hang of it. I like having some resistance from the keyboard when I play.

Maybe 15 minutes wasn't enough? As for it being a step down, I think it is more of a step sideways, with trade-offs in either direction. With piano you have velocity sensitivity, with a synth you have after touch, and an infinite array of different sounds.

I have a friend who plays jazz and blues in a piano bar during the week, plays electronic keyboards (including a Yamaha stage piano) in a blues/rock band on the weekend. He uses what fits the material, sometimes piano with one hand and synth with the other. He's the guy who suggested I get a digital piano and concentrate on that when I wanted to move up from the 61 key PSR I had bought for my daughter.

Most of the keyboard players I know started on piano, but that is largely a result of my growing up in Miami in the '60's. You learned on a piano, because there wasn't any choice, and then started gigging on a combo organ because it was portable and a Wurly or Rhodes cost more than your van. Everybody learned on an upright, none of this "it's got to be a grand" nonsense. A grand piano was what the guy in the sequined tuxedo with the candelabra played. Times have changed, my mother's neighbor has a Steinway in her double-wide, and a $200 keyboard is a science-fiction marvel compared to those old combo organs. My, how I ramble...

This is a very Piano dominated forum, naturally, but I'd like to hear from some synth players about their instruments being considered "a step down".

This is a very Piano dominated forum, naturally, but I'd like to hear from some synth players about their instruments being considered "a step down".

I assume you're referring to my comment. I was referring only to the action. A non weighted action, in my opinion, is a step down from a weighted action - and within weighted actions there are excellent and much less so excellent actions.