I have received two Audiomoths from round 3. Lovely designs and simple configuration. However, after some tests, I am annoyed by two common issues in the recordings. 1. I have quite plenty of destroyed signals of bat calls even with intermediate amplitude levels (usually <30%, low frequency noises included); 2. have gaps in some recordings, usually happened when recordings are destroyed a lot by the low frequency noises (at this case, the amplitude level are primary 70-100%). However, it also happened occasionally with low amplitude levels. I attached screenshots of the example here. [configuration: intermediate gain, 192 or 384k sampling rate, duty cycle: 3s on/12s off or 60s on/300s off, led light on/off] [detector setting-up: either in zip bag or not, height of detector 1-1.5m, weather generally humid, in some cases raining but the bag remind dry inside, temperature 80-90 F] . Many thanks first!
Performing oversampling while the data is in the low 12 bits is operationally easier since it minimizes overflow when adding values. If the data is in the high 12 bits then oversampling will reduce the noise within that range but the low four bits will always be zero and you do not get the benefit if the noise level is low. Adjusting the data to be in the highest bits can therefore be done after the oversampling. It is advantageous to ensure that overloaded signals are hard clipped to the maximum value so that it is always possible to identify any FSD value as having been clipped. If the overflow wraps round it becomes much more confusing and difficult to identify areas of overload other than by observing spectral anomalies.