  Inferring the source properties of a gravitational wave signal has
traditionally been very computationally intensive and time consuming. In recent
years, several techniques have been developed that can significantly reduce the
computational cost while delivering rapid and accurate parameter inference. One
of the most powerful of these techniques is the heterodyned likelihood, which
uses a reference waveform to base-band the likelihood calculation. Here an
efficient implementation of the heterodyned likelihood is presented that can be
used for a wide range of signal types and for both ground based and space based
interferometers. The computational savings relative to direct calculation of
the likelihood vary between two and four orders of magnitude depending on the
system. The savings are greatest for low mass systems such as neutron star
binaries. The heterodyning procedure can incorporate marginalization over
calibration uncertainties and the noise power spectrum.
