Instrumental music was supplied by a single flute-player, paid by the choregus. He was stationed in the orchestra, very likely upon the step of the thymele, and accompanied all songs. At times a harpist was added to the flute-player; Sophocles had great success with that instrument in his own _Thamyris_. At the end of a play the flute-player led the chorus out of the orchestra. The music itself is a subject complicated and obscure. Practically none of it has survived, and the details are naturally difficult to determine; but some main facts are clear. Though there was much singing and dancing the music composed by the tragedians was vastly more simple than that of a modern opera. All choral singing was in unison, and as a rule the words dominated the music.[186] The result was that an audience followed the language of an ode with ease, nor is it likely that such lyrics as those of the _Agamemnon_ or the Colonus-song, not to mention many others, which are masterpieces of literature, would have been written were they fated to be drowned by elaborate music. Nevertheless a distinct change took place even in the fifth century, owing chiefly to the eminent composer Timotheus, whose innovations were of course looked upon by conservative taste as corrupt; the comic playwright Pherecrates grumbles about the way in which his notes scurry hither and thither like ants in a nest,[187] a charge repeated almost in the same words by Aristophanes against Agathon. Euripides followed the new manner, and his novelties are brilliantly caricatured in the _Frogs_: the elaborate but thin _libretto_ and the trills.[188] The increasing use of monodies, or solos by an actor, which we find in Euripides—the exotic but effective performance of the Phrygian slave in _Orestes_ is a conspicuous instance—also points to the growing importance of musical virtuosity. Greek music was composed in certain modes (νόμοι), the precise difference between which is not clear, though the ethical distinctions are known. The Dorian mode was austere and majestic, the Lydian and Mixolydian plaintive, the Phrygian passionate.