  The spectrum of hybrid electromagnetic-spin-acoustic waves for magnetic
having conical spiral ferromagnetic structure defined by heterogeneous exchange
and relativistic interactions have been received. The possibility of resonant
interaction of spin, electromagnetic and acoustic waves has been shown. The
electromagnetic waves reflectance from the half-infinity layer of magnetic
having conical spiral ferromagnetic order has been calculated for different
values of external magnetic field (angle of spiral). The acoustic Faradey
effect has been considered.
