The controls for all inputs (including internal audio sources) as well as the Effects, Stream, Aux and Master output groups include a configuration button shown when you move the mouse over the input label.
The familiar ‘gear’ icon opens the advanced Audio Configuration panel.
We touched on this panel briefly when we discussed selecting and configuring Connections for external audio inputs. The Advanced Audio Configuration panel offers many more important features and controls, however. Let’s explore these now.
Audio and video arriving at TriCaster inputs will maintain sync throughout the system to output or recording. However upstream issues can occasionally cause video to arrive at TriCaster’s inputs later than the corresponding sound.
To mitigate this sort of external problem, TriCaster provides an adjustable Audio Delay setting.
E.g., many cameras support simultaneous digital and analog audio output. In-camera processing can delay digital a/v output, resulting in analog audio output actually leading the digital output by a meaningful measure.
The Audio Configuration panel also provides complete Pan control. Pan is a very useful feature. It adjusts placement of sound from source audio channels on the stereo channels comprising the audio mix (es).
Using Pan, you can place all or part of channel 1 onto channel 2, and vice versa.
- When Pan is set to the extreme left position for channel 1, its audio is sent exclusively to the first channel for the Input 1
- Centering the Pan knob labeled 1 splits the sound from Input 1 equally onto channels 1 and 2.
- Sliding Pan for channel 1 all the way to the right results in that source only being audible on channel 2, removing it completely from its original channel.
Pan also modulates the sound levels on the left and right channels so that the overall volume neither rises nor drops as a result of adjustments.
Hint: “Pan” is not the same as “Balance”. The balance control in a stereo system varies the relative level of the left and right channels, but sound from the left channel will never come out of the right speaker, or vice versa (whereas Pan does permit this to occur).
A main tab labeled Routing appears Configuration panel for all sources. The controls in this group determine output routing of the stereo pair(s) comprising the input group. Switches let you send input channels 1-4 to different channels on the internal audio buses maintained by TriCaster. Let’s talk about what an audio bus is and how it is useful before proceeding.
The Audio Mixer provides controls for each of these busses, allowing you to manage levels and signal processing. It is important to understand the distinction between busses and outputs. Now that we understand the former, let’s consider the latter.
For TriCaster purposes, an output may be physical, or virtual – i.e., it may involve a connector on the rear panel, or not. For example, the audio recorded by TriCaster does not necessarily require an output connector. Likewise, it may be analog or digital. Analog Outputs 1 and 2 (note that Output 2 is not a TriCaster Mini or Mini SDI feature) are permanently assigned to Master, and Aux 1 respectively. In contrast, digital (or ‘embedded’) outputs are configurable in the Hardware Configuration panel.
Sub-Mixes and ‘Mix Minus’
At times you may require specially configured audio mixes, typically using one of TriCaster’s two stereo Aux audio outputs. For instance – some installations call for sending audio from one or more internal sources (such as a DDR or the Sounds player) to a secondary distribution system.
Alternatively, you may want a ‘clean’ output from one or more sources for use apart from the main primary output mix. Specialized sub-mixes of this sort are often referred to as ‘mix-minus,’ since one or more sources are deliberately subtracted from the main program. Mix-minus capabilities can be invaluable for productions like ‘phone-in’ shows. The remote caller needs to be able to hear the interviewer; but if you simply send the primary mix back to him, he is forced to endure a late-arriving echo of his own voice. Needless to say, this would be confusing and undesirable.
Suppose your interviewer is speaking into a microphone connected to channel 1 of Input 1. The audio from your interviewee is routed into Channel 2. You could easily supply both to your Master bus for your program output needs, but remove channel 1 from Aux 1, and remove channel 2 from Aux 2 to provide mix minuses to send back to you different remote interviewees.
This approach eliminates annoying echoing, feedback and the like. Meanwhile, both participants can be heard on the main Program output. Also important, independent control and signal processing is provided for each part of the pipeline.
Hint: TriCaster Advanced Edition provides full 4x4 matrix routing for each source, allowing for much more sophisticated mixes than the simple example above.
The second tab in Audio Configuration is named Processing, and likewise holds very valuable features.
The seven-band equalizer allows you to ‘shape’ sound to taste, accommodate sources with different acoustic characteristics (say, mismatched mics), minimize feedback or roll off unwanted parts of the audio spectrum.
Enable or disable the Equalizer using the switch beside the label above its control group. The vertical sliders attenuate or boost the tonal range centered on the frequency shown at the top.
The Compressor/Limiter is capable of preventing clipping (see Section 15.8.1) from unexpected peaks or transients, and making talent sound better than they do in real life, bringing voices, music and other audio sources into an optimal dynamic range. Being able to do this independently for each output too is icing on the cake, especially for Internet streaming, as it ensures correct levels at any time.
Sound above the set Threshold level will be compressed; the amount of compression and the manner in which it is applied are both dictated by the other settings.
A Ratio of 4:1 means that if input level is 4 dB over the threshold, the output signal level after compression will be just 1 dB over the threshold. The gain (level) is reduced by 3dB. Very high ratio settings are the reason the word “limiter” is part of the title for this feature. The highest ratio setting will effectively reduce any signal that would rise above the threshold all the way down to the threshold level (with the exception of a brief period during a sudden increase in source loudness, as dictated by the Attack setting).
Attack (like Release) is labeled in milliseconds. The setting represents the amount of time it takes for the gain to change by a specified amount.
It would not be grossly incorrect to think of this setting as changing the slope of a graph depicting how aggressively the compressor pursues the target value (defined by applying the Ratio setting to the amount the signal surpasses the Threshold). Shorter values are more aggressive, while longer values are more subtle (and tend to be less noticeable to the audience).
Release is similar to Attack in many ways, but refers instead to the speed with which the compression effect is removed as a source signal falls back on its own so that it no longer exceeds the Threshold.
Naturally, compression impacts the overall output level of the source or output. The Gain control allows you to compensate, bringing the post-compressor/limiter signal back to a comfortable nominal range.
Hint: Different circumstances call for different Attack and Release strategies. For example, much less aggressive settings could work nicely for vocals, but fail badly when applied to a snare drum. Many websites provide suggestions on establishing the best compressor/limiter settings for different environments.
The Audio Mixer’s advanced options panel also include a configurable Noise Gate for each audio source, as well as all outputs. This lets you ensure that unwanted low-level sounds are prevented from inadvertently intruding into the mix.
Hint: When the corresponding video source is not displayed on output, the audio source’s VU meter level is displayed as a grayscale.
Run Macro at
The nearby Run Macro at (value in dB VU) is part of TriCaster Advanced Edition’s powerful automation toolset. Click the E (Event) button to assign macros to run when the sound level for the input passes the threshold audio level (transients such as a brief cough are filtered out).
In this manner you could, for example, automatically perform a ‘hands-free’ camera switch to show someone who begins speaking, and then automatically switch back again when he stops.
For more information please download the entire document at new.tk/rt-m