No definitions found for 'upper frequencies'
Perhaps one of these:
upper paleolithic,
upper bench,
upper fruitland, nm,
upper black eddy,
upprop,
upper fruitland,
upper balcony,
upper peninsula,
upper falls,
upriver,
upper avon river,
upper bound,
upper providence township,
upper providence township, pa,
upper avon,
upper brookville, ny,
upper volta,
upper berth,
upperville,
upper pharyngeals,
upper brookville