One of the most physically challenging tasks facing a broadcast engineer is riding the faders to maintain a smooth, balanced mix in the fast paced environment of a multi microphone talk show. SSL’s unique Dialogue Automix is an option available for C10 and C100 consoles which provides software driven automation of this process. The Dialogue Automix system assists skilled and unskilled audio mixers in managing multiple live mics without having to continually ride their individual faders to eliminate spill and room colouration. Once a relative level has been set for each microphone, the system detects which mics are receiving an input and makes fast, transparent crossfades between them, freeing the mix engineer to focus on balance and sound quality rather than be chained to the faders. These voice-controlled crossfades closely track unpredictable dialogue, eliminating cue mistakes and late fade-ups, while avoiding the choppy and distracting effects common to noise gates. The overall gain of multiple active channels is automatically adjusted to keep the overall output equivalent to a single channel, thus eliminating obtrusive fluctuations in background noise when more that one channel is contributing to the mix.
Dialogue Automix is freely assigned on a per channel basis up to a maximum of 16 channels. The system can be used with a mixture of local and remote sources, so not all the contributors have to be in the same location. The algorithm will work perfectly happily with someone on the end of a telephone line or at the end of a remote. The system provides a ‘Weight’ control on each channel which lets the operator establish relative ‘priority’ for individuals when multiple channels are open at once. The primary use of the weight control is to enable to host to ‘talk down’ other show participants. Lowering the weight control on a channel decreases the channel gain during ambience and lowers the relative gain if the channel is active with other channels. Raising the weight, increases the gain during ambience and increases the relative gain if that channel is active with other channels. It is also possible to globally adjust the automatic fade-in and fade-out times used by the Automix algorithm: The Attack time constant controls the fade-in rate and should normally be set at to a fast rate (around 1ms) to avoid an audible fade in on the start of a word. The Release time constant sets the rate of return to the ambient gain setting to avoid pumping effects between words. Automix activity is shown in the Channel displays with clear indication of which channels are assigned to Automix and level meter indication of individual channel gain reduction.