I have found over the years that if you call and you don't get a response it does not mean there are no elk there. The elk are there they are not vocal for a reason.
I watched a cow elk run up and kick the crap out of a calf one time because it called back to me. That heard was on high alert. So the cows also know what's up.
If the Heard is not talking then you should not be talking. In those instances I usually am listening for brush snapping and breaking or the sound of hooves hitting the ground heavily. Then I will attempt to make a silent approach and when I know I am in the bedroom and only when I am really close will I hit the bugle. This will typically bring the bull running in.
Also If the cows are not in heat yet the bigger bulls will be out looking for hot cows just like a big buck. So early on sometimes all you need is the cow call. The last two bulls I called in were very vocal and all by themselves and were busy looking for the cows. There were no cows anywhere to be found so they readily came to the bugle mixed with cow calls. The 5x7 only responed when I mimiced his call which was a very short growly call. When I did that he came on a slow trot all the way in. He did not respond at all to the higher piched call or the cow calls. Another bull also came in to the growly bugle unfortunately my buddy missed his shot.
Another thing is, like Polar Bear said, is to repeat what they say back at the. I did that on the last two bulls I killed and it worked like a charm. If the bulls are raspy or growly you can make that sound by humming while you blow on the tube call etc. Hum deep for a deep growl hum high for a high pitched growl. It may take some practice but it works very well once you master it.Just a few things I have learned over the years.
