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The frequency-mass relations of QPO black holes are explained by an epicyclic double resonance of Ωφ/Ωθ=3:1 and Ωφ/Ωr=13:1 for a spin ac=0.99622. Among the sources considered are the 3:2 frequency ratio, ́twin-peak ́ black holes and Sgr A*. The QPOs are suggested of generating resonant waves in the space bounded by the ISCO and the outer ergosphere surfaces. The physics are based on the non-Keplerian gravitational potential previously discovered in the Kerr metric. This characteristic is fundamental for the activities of most rapidly spinning black holes leading eventually to a resonance disaster of the black-hole/disk system.

A Model for High and Low Frequency Oscillations in Black Hole Accretion Disks including Sgr A*