An important task at the soil compaction of foundations is to assess the quality of their laying after dynamic vibration processing. This task is necessary to determine the density and physico-mechanical properties of soil after compaction, which defines reliability and durability of foundations and structures. In the slightly wet ground with layer-by-layer stacking this task is solved by selecting soil samples in each compacted layer of the foundation. The author of the article has conducted comparative tests of different methods of soil sounding (static, shock, vibration and explosive) and claims the possibility of their usage to assess the properties of water-saturated sandy grounds after dynamic vibration deep compaction.