When they' re on the roost, turkeys are pretty much quiet during the night.
Locate the flock in the late afternoon, and watch where they start heading towards sunset. That' ll narrow down your search area. The next morning, get into the area before sun-up and listen. If you hear them, I wouldn' t do any calling. If you don' t hear anything once the sun is up, you might yelp a few times to see if they' ll respond. When hens flydown, many may cackle a lot. Even if they don' t you may hear them flying. Turkeys flying through trees & cover can make a bit of noise.
I remember one in AL that sounded like a thrashing machine on overdrive as it rocketed through some pine trees.
Once you' ve located the roost tree(s), I' d try to stay out of the area if I could. How far? I' m sure that' s question better answered by the more experienced gobble-stalkers.....but I' ll venture that cover has a lot to do with it. Inside of 100yds your chances of getting busted may increase a lot.