In a method and magnetic resonance (MR) apparatus to acquire spin echo-based MR signals of an examination subject with a multi-spin echo sequence with multiple refocusing pulses after a single excitation pulse in an MR system that has a multichannel RF transmission and reception module: detect a spatial, two-dimensional phase distribution in the examination subject is detected by acquiring navigator signals, a phase and amplitude distribution for the individual transmission channels of the RF transmission and reception module is calculated to generate a magnetic field B1 for one of the RF refocusing pulses to generate the spin echo-based MR signal under consideration of the spatial phase distribution of the navigator signals, and this RF refocusing pulse is radiated via the multichannel RF transmission and reception module with the calculated phase and amplitude distributions of the individual transmission channels.