No, not quite. A threaded headset is the same as a non threaded one in that the crown race and the races in the head tube are pressed in. Where it varies is that the adjustable race (at the top) is screwed on followed by a lock nut. This leaves a hole down the middle where the quill stem goes.
Here a picture from the interweb which hopefully shows the difference (though is complicated by lots of spacers and washers which makes it more difficult to understand than it should be)