An important variant on traditional sonata-allegro form is found in the first movement of the Classical concerto. Here, the sonata-allegro's customary 'repeated exposition' is replaced by two different but related sections: the 'tutti exposition' and the 'solo exposition'. Prototypically the 'tutti exposition' does not feature the soloist (except, in early classical works, in a 'continuo' role), and does not contain the decisive sonata-exposition modulation to the secondary key. Only when the 'solo exposition' is under way does the solo instrument assert itself and participate in the move to (classically) the dominant or relative major. The situation is only seemingly different in the case of such late classical works as Beethoven's piano concertos No. 4 and No. 5, where the soloist is heard at the outset: as the later unfolding of those movements makes clear, the opening piano solo or early piano flourishes actually "precede" the start of the exposition proper. This device is also found in an early Mozart concerto, No. 9, as well as in many Romantic concertos, such as Grieg's A minor concerto or Brahms' B major concerto.