Lectrosonics DMTH4 - Telephone Interface and Digital Matrix ProcessorThe DMTH4 integrates telephone lines, video codecs and external audio sources into the digital bus structure of DM Series processors so these sources operate as though they are another microphone or audio input in the sound system. The unit is much more than just a telephone interface. Instead, it is a complete DM Series digital matrix processor, with a 3 in 24 out digital matrix, automatic mixing and comprehensive signal processing on every input and