Growing up in Houston, I heard these bugs every Summer. At times it was pretty loud when they would all reverberate together. You could also find the exuviae (or exoskeletons they would leave behind after moulting). When we first moved to Texas, I found tons of these bug shells still clinging to the trees around the house so I carefully removed a good number of them, attached them to my shirt and then ran into the house pretending I was attacked by insects. Nearly gave Mom a heart attack!