This article brings up the vocal sounds of the Shiroishi dialect as part of the descriptive research that is beingdone on the various Tohoku dialects. It is primarily reporting the true condition of this dialect as it differs bygeneration. Specifically, it brings up the following six vocal sounds: 1) the unification of /i/ with /e/, 2) theunification and voicelessness of /si/ with /su/, 3) the combining of the consecutive vowels /ai/ and /oi/, 4) thevoiced consonants /k/ and /t/, 5) the nasalization of the consonants // and /d/, and 6) the palatalization of /ki/.Shiroishi city is located in the southern part of Miyagi prefecture, and in the past, it flourished as the castle townaround Shiroishi castle. Moreover, within the division of dialects, it belongs to the Nanou dialect family, and theabove-mentioned 1)-6) are all considered to be vocal sound phenomena that are characteristic of this dialect. Theaim of this article is to clarify how all of these vocal sounds show the actual state of the dialect as it differs fromgeneration to generation within the progression of the recent striking standardization of the language. This studyused 10 men and women from elderly, middle aged, young, and adolescent age groups as its basis, and the vocalsounds that were obtained were objectively grasped through an acoustic analysis. Moreover, this comparison willnot only simply determine if these phenomena are present, it will also endeavour to be able to trace the variousphases of the gradated process where original dialect sounds gradually decline. This will be done through thingslike visually understanding the small differences or similar conditions in the parts of words that are articulatedusing an analysis diagram. The results of this comparison made it clear that within above-mentioned vocal soundphenomena, there are both sounds that are quickly declining or already at a terminal stage (these are especiallystriking when compared with other Tohoku dialects that have undergone similar large group studies) and soundsthat are still leaving deeply rooted vestiges. This article's significance and achievements lie in its objectiveclarification of the actual condition of the vocal sounds of a specific dialect through a large group study of differentgenerations and an acoustic analysis of the study.