Answer Detect Threshold (dBm)

Parameter group

Trunk Interface

Access level


Possible values

-43 through -25




Some CAS protocols do not provide positive answer supervision (for example, FXS, SAS, and Remote Extension (RE)). For this type of protocol, Blueworx Voice Response tries to detect voice energy to indicate that a call has been answered. Voice energy is characterized as being made up of more than two frequencies and has a different energy distribution from call progress tones (such as ring back or busy tones).

This parameter specifies the minimum level of audio signal (more than two frequencies) that must be present for a time equal to or greater than that specified by Answer Detect Time, to determine whether an outbound call from Blueworx Voice Response has been answered.

This parameter applies only to signaling protocols that do not return answer supervision.

Note: This parameter has been set to a default value that works well with a large variety of telephony installations. Reliable voice detection is a balance between rejecting noise or distorted call progress tones, and having enough sensitivity to detect a caller who speaks quietly or speaks only a short greeting.

If this value is set too low, you will get many false voice detections. If this value is set too high, the caller will have to speak quite loudly to cause voice detection.