  We evaluate the sound attenuation in a Weyl semimetal subject to a magnetic
field or a pseudomagnetic field associated with a strain. Due to the interplay
of intra- and inter-node scattering processes as well as screening, the fields
generically reduce the sound absorption. A nontrivial dependence on the
relative direction of the magnetic field and the sound wave vector, i.e., the
magnetic sound dichroism, can occur in materials with non-symmetric Weyl nodes
(e.g., different Fermi velocities and/or relaxation times). It is found that
the sound dichroism in Weyl materials can be also activated by an external
strain-induced pseudomagnetic field. In view of the dependence on the field
direction, the dichroism may lead to a weak enhancement of the sound
attenuation compared to its value at vanishing fields.
