How much of Nashville TN had this off hook tone

How much of Nashville TN had this off hook tone? I saw that there were several Tennessee Telephone Company Inc. offices in Tennessee with ATT/Philps Tel 5ESS-PBX Host switches around there. So how much of Nashville TN had this off hook tone? I still wanna know what kind of off hook tone this was an what the technical name for this off hook tone is. Thank you.