  We use the ESPRESSO spectrograph at the Very Large Telescope to measure
velocity shifts and gravitational redshifts of eight bona fide Hyades white
dwarfs, with an accuracy better than 1.5 percent. By comparing the
gravitational redshift measurements of the mass-to-radius ratio with the same
ratios derived by fitting the \textit{Gaia} photometry with theoretical models,
we find an agreement to better than one per cent. It is possible to reproduce
the observed white dwarf cooling sequence and the trend of the mass-to-radius
ratios as a function of colour using isochrones with ages between 725 and 800
Myr, tuned for the Hyades. One star, EGGR\,29, consistently stands out in all
diagrams, indicating that it is possibly the remnant of a blue straggler. We
also computed mass-to-radius ratios from published gravities and masses,
determined from spectroscopy. The comparison between photometric and
spectroscopic stellar parameters reveals that spectroscopic effective
temperature and gravity are systematically larger than the photometric values.
Spectroscopic mass-to-radius ratios disagree with those measured from
gravitational redshift, indicating the presence of systematics affecting the
white dwarf parameters derived from the spectroscopic analysis.
