"It was of course recognized that the Old Testament not only spoke approvingly of the use of music (including instruments) in worship, but even commanded it. However, in the Hellenistic church, derived principally from Gentile roots, the music prescribed by the Torah for Jewish ritual was thought to be an accommodation by God to the weaknesses of the covenanted people--much like the permission of divorce in the Law of Moses. The fathers supported their position by quoting out of context such passages as Amos 5:23--'Away from me with the noise of your songs; the playing of your harps I do not wish to hear'--and Isaiah 5:12--'they have lyre and harp, timbrel and flute and wine at their feasts; but they do not regard the deeds of the Lord.' As far as Christian worship is concerned, they interpreted the instruments allegorically as representing powers of the soul and mind. Thus, for example, Pseudo-Origen writes that when the psalm says, 'Praise him in the sound of the trumpet,' the 'trumpet' is to be understood as the contemplative mind."
My point in citing this passage is to show that the early church Fathers perhaps took some biblical passages out of context and also let their everyday assumptions (preapprehensions) or philosophical views govern their interpretation of both the Old and New Testament.
Generally, from what I've read, the pre-Nicenes totally disapproved of secular love music; but maybe they qualify these sentiments somewhere. In any event, here are some examples of their overall attitude toward love/secular and instrumental music:
"In W. Riedel we read among the Commandments of the Fathers, Superiors and Masters that:
Christians are not allowed to teach their daughters singing, the playing of instruments or similar things because, according to their religion, it is neither good nor becoming.
All these passages, it is true, are concerned with worldly song and worldly music, to the practice of which pagan women attached excessive importance . . . In contrast to this the singing of psalms was recommended again and again to Christian virgins precisely as a substitute for prohibited secular music. Tertullian writes:
Let the two [spouses] sing psalms and hymns and incite each other to see who can sing better to his God" (information taken from J. Quasten's Music and Worship in Pagan and Christian Antiquity, pages 83-84).
"The reasons for which Christians passed their sharp judgment were other than those of the pagans. It is true that Christians also held music in contempt because it promoted moral decay. Thus Clement of Alexandria condemned flute music because it was 'a chain in a bridge of sensual love and idle impulses,' and he rejected the noise of cymbal and tambourine because it made one forget propriety and morality. But the most important reason for Clement's condemnation of profane music in private life, which all other Christian writers shared with him, was the close relationship between music and the pagan cult of the idols. Therefore all the music of that time, as far as Christians were concerned, constituted one great worship of idols" (ibid. 126).
"God also gave man a voice. Yet, love songs and indecent things are not to be sung merely on that account" (Cyprian, ANF 5.433).