Digital Telephone Hybrid

The DMTH4 from Lectrosonics is an 3-input, 24-output matrix mixer, that allows for connecting telephone lines, video codecs, along with other audio sources, into the digital bus structure of DM Series processors. The unit treats the "non-regular" audio sources as if they were microphone or line inputs, with DSP available on both input and output, including filters and compression. Up to 128 macros can be stored in internal memory.

The unit is suitable for sound reinforcement applications, recording in boardrooms, courtrooms, worship centers, distance learning systems and hotels, and wherever teleconferencing is part of the system requirements. It tackles the issue of echo being heard at the originating source (the "far end"), due to the signal from loudspeakers entering microphones at the local room, and being sent back to the "far end" location.

DMTH4 features include:

• 3-input/24-output digital matrix processor in a stackable configuration
• Fully integrates with DM Series processors
• Telephone, codec and auxiliary inputs and outputs
• Two acoustic echo cancellers - 126 mSec tail time
• Line echo canceller - 30 mSec tail time
• Six filters plus compressor on each input
• Six filters and compressor/limiter on each output
• USB and RS-232 interfaces for setup and comprehensive remote control
• Fully balanced audio signal flow throughout entire system
• Digital I/O ports for "daisy chaining" and to connect other LecNet 2 devices
• Proportional gain auto mixing algorithm with AutoSkew
• Simultaneous LecNet2 software and third-party control