Sound frequency: bees also communicate by sound, mainly by changing the frequency of the sound emitted. From the frequency of sound, we can identify the missing bee queen (bi-gray). In the same way, we identify the bee’s readiness to swarm. The standard frequency for fixed hives is up to 200 Hz. As the hive prepares for swarming, the frequency increases to 240 Hz. If the hive is in a swarming mood, the frequency will rise to over 270 Hz. If the frequency of the sound exceeds 300 Hz, the bee colony will soon appear (due to the current weather).
Amplitude: total noise from the hive. From these data, the activity of the hive or the response of the hive to various stimuli such as treatment, nectar laying, encroachment attack, and others can be read. Data range from a few units in winter to tens to hundreds for strong bee colonies in summer.
The curves above show indications for swarming how relative strength/intensity A(dB) versus frequency (Hz) increases over time for respectively 3 weeks, 5 days, and one day before swarming.
In the web service and mobile app, you can see the evolution of the frequency and the slope of the curve, over time. The frequency analysis should normally have a descending slope from the lower frequency bands to the higher frequencies.
If the frequency band does not have a normal downward slope after a period of time, then there is a reason to check the beehive.