Prism Sound ADA-8XR Multi-channel A/D D/A Converter Module Reference - Revision 1.01
© Prism Media Products Limited, 2001-2005
Page 3.11
3.4.3 AI Line Trim menu
The AI Line Trim menu is a Per-Channel Selection menu. The user may finely trim the line-up
level for each of the eight channels by ±0.5dBu in 0.05dBu steps. This control is
supplementary to the AI Line Level menu.
A real-time display of the peak metered level of the current channel is provided on the bottom
line of the screen to facilitate adjustment. The level display shows peak amplitude in dBFS,
i.e. dBs below digital full-scale. Although it should not be necessary to trim the ADA-8XR to
produce accurate line-up levels (the ranges are set very accurately at the factory), line-up with
other equipment can be achieved by connecting the external reference level to the ADA-8XR
and adjusting the trims as follows. If, for example, a +4dBu (0VU) tone is connected, and the
ADA-8XR line-up is being adjusted for 0dBFS=+18dBu, each trim should be set so that the
peak level display reads as close as possible to -14dBFS. Note that the peak level display
does not function when ‘All’ is selected (it cannot show the level of all eight channels at the
same time!).
3.5 Module Dependent Factory Default Stores
Several of the Factory Default Stores (which include A/D Paths) depend on the fitment of an
analogue input module of some kind for correct operation (as described in the Firmware
Reference). If no analogue input module is available, loading these Stores results in any
available input module being assigned to the ‘analogue input’ Path, or no input module being
assigned if there is none available.
3.6 Specifications
Unless otherwise stated, all performance specifications are rms, unweighted, band-limited
20Hz-20kHz, sampling at 96kHz, wordlength 24-bits, analogue I/O line-up at 0dBFS=+18dBu.
Electronically-balanced inputs on female XLR connectors (pin 2 hot)
Differential input impedance: 21k5
Ω
Full-scale input range (software controlled):
Range: +5dBu..+24dBu in 0.5dB steps
Trim: ±0.5dB in 0.05dB steps
Absolute gain accuracy: ±0.05dB
Common-mode rejection ratio (CMRR):
60Hz: <-100dB
1kHz: <-90dB
20Hz..20kHz: <-65dB
Overkiller (progressive analogue input limiter):
On/off selection per channel
Automatic software-controlled threshold adjustment
THD+n (997Hz, -1dBFS): -110dB (0.0003%) typical
Dynamic range (997Hz, -60dBFS): 115dB typical
IMD (SMPTE/DIN, 60Hz at -3dBFS and 7kHz at -12dBFS): <-100dB
Maximum aharmonic spurium: (997Hz, -1dBFS): <-130dBFS
AI1 Lin:+0.00dB
-1.02 [Trim]
