Data Acquisition Above Threshold

Hello,

I started with LabVIEW a few days ago and find it quite difficult. Hope that you can help me a bit.

My task is: 2 channels (from acoustic sensors), I need to find time delay of arrival between them and then compute the coordinates of a source that emits acoustic waves. So, I considered multiple examples that I managed to find and I am finally stuck at the very beginning. 

I need to work with signals (impulses) that are higher than a specific threshold, but how can I do that? Do I need to use Threshold Detector.vior not? 

Then I need to find time delay of arrival. Should I use CrossCorrelation.vi? 

Thanks a lot.