This dataset contains raw sound velocity data acquired with the Sound Velocity Profiler MIDAS SVP 6000 during cruise PS135/1 aboard RV Polarstern. A total of eight casts were conducted, each reaching a target depth of 1000 meters. However, due to an instrument malfunction at station PS135/1_4-1, no data were recorded for that cast. The final dataset includes raw sound velocity data from seven successful casts in both binary (.BIN) and ASCII (.000) file formats. The data were used for calibrating acoustic systems used during the cruise.