NewTek TriCaster TC1 (2 RU) - Manual (Page 49)

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L ocal connections can be assigned to ‘listen’ to either an SDI embedded audio source connected to the
corresponding video input, or analog audio inputs provided on the unit (varies by model). Choosing a local
hardware audio source causes another menu to be displayed at right, which is where you can choose whether
to connect to sound from the
Embedded (SDI) or analog hardware input (Line or Mic level, varies by model).
Note: Analog audio levels conform to SMPTE RP-155. The maximum input/output level is +24 dBu and the
sample rate is 48 kHz.
Beyond this, you have the option of assigning the audio delivered over the network from any NDI or other
supported network audio sourc
e (such as Audinate’s Dante™ sources) available on the system.
Returning to the audio Input Configuration panel, note that it holds both basic and advanced audio features.
In the former category, volume sliders are provided below VU meters for each audio source and output.
Source sliders default to their 0dB gain setting on first launch. After adding audio sources, adjust these
sliders as required.
Hint: Most numeric controls in the interface can be reset to their defaults using Shift + double-click on the
control knob. The default value for Gain sliders is 0dBVU.
A UDIO H EADROOM
In digital audio systems, levels exceeding ‘legal’ values are ‘clipped’ (uniformly assigned the maximum value).
This results in audible issues that cannot be easily corrected later. For this reason, it’s customary to configure
normal operating level (also referred to as the ‘alignment level’, and sometimes, ‘nominal level’) well below
the clipping limit – sufficiently so that occasional excessively loud sounds (say, loud laughter or applause)
can be accommodated without risk.
This range above between nominal level and the highest possible level is commonly referred to as ‘audio
headroom’. What is considered a suitable headroom allowance can vary from one locale to another, in
different industry applications, and even in individual studios. NewTek systems follow well-established
audio conventions, providing 20dB of headroom above nominal level (+4dBu at 0dB on the VU scale).
Hint: Confusion can sometimes arise because different calibration scales are common in various audio realms,
and even for different device types and software.
For example, analog mixers commonly show levels on VU scales indexed as just described. In contrast, digital
devices and editing software usually display levels in dBFS (Decibels Full Scale) with 0dBFS
– the absolute
maximum signal level that can be recorded – at the top. NewTek VU meters have selectable indexing, allowing
you to view a traditional dB VU scale or dBFS as you please (see Section 16.9.1).
Whatever scale you choose, use Volume controls (and, for Mic connections, the Gain controls in the
Configuration panel ) to avoid over-modulation. The Compressor/Limiter feature (also located in the Audio
Configuration panel) is another powerful tool to help you prevent clipping – see Section 16.10.
SECTION 3.13
CONFIGURE GENLOCK
Enable and configure this feature (not supported on TC Mini) as follows:
1. If the Live Desktop isn’t already open, l aunch a live production session from TriCaster’s Home page.