Charles Spurgeon Commentary Amos 6:5

"that sing idle songs to the sound of the viol; that invent for themselves instruments of music, like David;" — Amos 6:5 (ASV)

But not for the same purpose as David played and sang; his instruments of music were used for spiritual solace and the worship of God; but these people used their ingenuity to discover how their music might inflame their lusts and be a vehicle for the expression of their lascivious desires.