I'm not exactly sure what the question is. Are you saying you want to know how many bees you would have to record buzzing to make it sound like a hive full?
The intensity varies depending on the situation, from the quiet hum of a happy hive to the lawn mower sound of a hive in the process of swarming. I did some recording by putting one microphone at the hive entrance and one inside on the top bars. The problem I had was that bees walking on the microphone or buzzing close by were really loud. At the time, I was making the recording to play inside an empty hive I had on display at a science museum to make it sound real.