Speech Reinforcement Calculator (SRC)

Potential Acoustic Gain (PAG)
dB
Maximum theoretical gain that can be achieved without feedback
Gain lost through NOM
dB
Every open mic creates a potential feedback path and thus reduces your PAG
PAG after accounting for NOM
dB
PAG minus gain loss due to NOM
PAG after accounting for NOM and FSM
dB
To avoid running the system on the verge of feedback, the PAG value is further reduced by the FSM
Needed Acoustic Gain (NAG)
dB
The gain required for the farthest listener to hear the talker at the same level as the nearest listener
Should you be safe from feedback?
As long as (PAG - NOM - FSM) > NAG is true, then you should be safe from feedback
Distance from the Talker
To their microphone
To the nearest listener
To the farthest listener
Distance to the Nearest Loud Speaker
From the talker's microphone
From the nearest listener
Open Microphones and Stability Margin
Number of open mics (NOM)
Feedback stability margin (FSM)