  We present a new mechanism for core-collapse supernova explosions that relies
upon acoustic power generated in the inner core as the driver. In our
simulation using an 11-solar-mass progenitor, a strong advective-acoustic
oscillation a la Foglizzo with a period of ~25-30 milliseconds (ms) arises ~200
ms after bounce. Its growth saturates due to the generation of secondary
shocks, and kinks in the resulting shock structure funnel and regulate
subsequent accretion onto the inner core. However, this instability is not the
primary agent of explosion. Rather, it is the acoustic power generated in the
inner turbulent region and most importantly by the excitation and sonic damping
of core g-mode oscillations. An l=1 mode with a period of ~3 ms grows to be
prominent around ~500 ms after bounce. The accreting protoneutron star is a
self-excited oscillator. The associated acoustic power seen in our
11-solar-mass simulation is sufficient to drive the explosion. The angular
distribution of the emitted sound is fundamentally aspherical. The sound pulses
radiated from the core steepen into shock waves that merge as they propagate
into the outer mantle and deposit their energy and momentum with high
efficiency. The core oscillation acts like a transducer to convert accretion
energy into sound. An advantage of the acoustic mechanism is that acoustic
power does not abate until accretion subsides, so that it is available as long
as it may be needed to explode the star. [abridged]
