<< what I meant was a music keyboard also I would want one that alread has the speakers built into the keyboard I dont want to buy an amp >>
I really don't mean to sound condescending here, but if you have $4000 to spend on a "high end" keyboard and you're making a statement like this you need to either: A) Do your homework on keyboards B) spend ~$700 on a good Yamaha PSR-series and donate the rest to a save-the-music type charity.
You could go out and buy a Korg Triton or a Kurzweil K2500 or even a Yamaha Motif, but unless you know much more about keyboards (not pianos or organs, keyboards) than you're letting on, 90% of the instrument will never be used. I wish I had a dime for every amateur musician out there with more money than knowledge that bought one of the aforementioned keyboards because they "wanted the best" but ended up hating it because they had no conception of its capabilities.
Now, I say all this assuming you want a keyboard and not a digital piano. If you want a good digital piano, you can easily spend $4000. I would recommend going to a music store and trying out all the models in your price range and see which one you like best. There are up and down sides to each brand and product series and only you can determine exactly the features you want.