Lectrosonics AM8TC - Automatic Microphone Mixer with Digital Control and High and Low Tone Controls

The AM8TC from Lectrosonics is an eight channel audio mixer with digital control, that provides APG (Adaptive Proportional Gain) for up to eight microphone/line inputs. Suitable for sound reinforcement, teleconferencing and recording set-ups, the unit provides a clean signal path with transparent level control. Rear-panel switches allow for accommodating line levels, phantom power and dynamic microphone levels.

The AM8TC is primarily set up utilizing the front-panel volume controls. The DSP algorithm then allocates the gain applied to each channel after comparing the individual channel level with an overall reference level. Since the reference is a mix of all the channels, the unit is able to adapt to varying noise levels in the immediate surroundings.

The channel with the most signal receives the most gain, with the algorithm keeping track of which channel is the most active (loudest for the longest time) and allocating a priority to that channel. The automatic mixing action is inaudible and skewing is damped to keep it from responding to brief signal transients. Remote control of channels is also provided.

To maintain a consistent level and protect amplifiers, the unit includes a very smooth compressor/leveler, in effect making the AM8TC a complete automatic level control system. An RS-232 port allows most of the functions of the unit to be controlled either by a computer or a dedicated control system, such as AMX or Crestron.

The AM8TC includes both high and low shelving type tone controls for each channel, with +/-10dB of gain/cut at 100Hz and 1kHz.