Front Panel Overview

Figure 1 - Front panel controls

The Input Level Meter (A) monitors the signal going into PDM II’s processing circuit. As they follow the A/D converter in the signal path, they will accurately monitor the input regardless of the Input Sensitivity setting.

Note that this is a peak meter to be used as a diagnostic tool for setting input levels; it does not display RMS voltage or a time-integrated level and is not intended to be a replacement for a more sophisticated loudness meter.

  • Four dark LEDs: The input signal is below -36 dBFS.

  • One Green LED: The input signal is above -24dBFS.

  • Two Green LEDs: The input signal is above -18dBFS.

  • Three Green LEDs: The input signal is above -12dBFS.

  • Four Green LEDs: The input signal is above -6dBFS.

  • Top LED is Yellow: The input signal is above -0.5dBFS.

  • Top LED is Red: The input signal is above +0.5dBFS.

  • All LEDs are Yellow: The unit is expecting a Livewire input but not seeing a valid signal, or there is an internal error.

The LCD display (B) shows a variety of information about the current status of the PDM II and provides a menu system for front-panel setup and configuration.

The navigation cluster (C) is made up of left, right, up, and down arrows plus a green "checkmark" button (generally used as an "Enter" button to confirm choices) and a red "X" button (used as a "Cancel" button to exit a menu without saving any changes).  

The main color-coded operational buttons are grouped together and their use in actual operation is outlined in greater detail in the Front Panel Overview and Basic Operation sections, but in short:

  • The green Build button (D) starts building a delay at the start of a program.

  • The yellow Exit button (E) starts the process of exiting the delay to return to real-time audio.

  • The blue Cough button (F) temporarily stops incoming audio from reaching the delay buffer

  • The red Dump button (G) dumps the buffered audio or plays a pre-recorded audio file when a guest, caller. or even the talent (!) utters something objectionable that should not be aired.

The Bypass button (H) is used for emergencies or when you want to electrically remove PDM II from the signal path. Pressing it connects its outputs directly to its inputs with no processing or delay, and also clears the PDM II's delay memory.

Note: PDM II also goes into electrical bypass - connecting the analog and AES/EBU RJ45 inputs to the corresponding RJ45 outputs - when power is removed. In this situation, the PDM II becomes a completely passive device with no level adjustment or A/D conversion taking place.