  We study the formation of coalescing binary black holes via the evolution of
isolated field binaries that go through the common envelope phase in order to
obtain the combined distributions of the main observables of Advanced LIGO. We
used a hybrid technique that combines the parametric binary population
synthesis code COMPAS with detailed binary evolution simulations performed with
the MESA code. We then convolved our binary evolution calculations with the
redshift- and metallicity-dependent star-formation rate and the selection
effects of gravitational-wave detectors to obtain predictions of observable
properties. By assuming efficient angular momentum transport, we are able to
present a model that is capable of simultaneously predicting the three main
gravitational-wave observables: the effective inspiral spin parameter
$\chi_{eff}$, the chirp mass $M_{chirp}$, and the cosmological redshift of
merger $z_{merger}$. We find an excellent agreement between our model and the
ten events from the first two advanced detector observing runs. We make
predictions for the third observing run O3 and for Advanced LIGO design
sensitivity. We expect around 80% of events with $\chi_{eff} < 0.1$, while the
remaining 20% of events with $\chi_{eff} \ge 0.1$ are split into ~10% with
$M_{chirp} < 15$ M$_\odot$ and ~10% with $M_{chirp} \ge 15$ M$_\odot$. In
conclusion, the favorable comparison of the existing LIGO/Virgo observations
with our model predictions gives support to the idea that the majority, if not
all of the observed mergers, originate from the evolution of isolated binaries.
The first-born black hole has negligible spin because it lost its envelope
after it expanded to become a giant star, while the spin of the second-born
black hole is determined by the tidal spin up of its naked helium star
progenitor by the first-born black hole companion after the binary finished the
common-envelope phase.
