m908 User Manual, Rev. G
•
16 channel ADAT Lightpipe In / USB 24 channel In
•
AES3, S/PDIF, and TOSLINK Stereo In
•
Optional Dante™, DigiLink™ or MADI module for additional 32 channel I/O
•
Optional 8 channel ADC module for 8 or 16 channel analog inputs
•
Optional high performance RIAA phono preamplifier for MC and MM cartridges.
•
Flexible Meter outputs
•
Built in SPL meter
•
Dual redundant external power supply
•
Reference quality headphone amplifier with cross-feed.
•
Flexible talkback system with built-in mic on remote control and mic input for external
talkback mics
•
Up to 8 stereo CUE paths
•
4 General Purpose Input and Output pins for interfacing to external systems.
The m908 consists of three components: ACU (Audio Control Unit), RCU (Remote Control Unit), and
PSU (Power Supply Unit) Below is a description of the connections, controls, and indicators for each
component.
3.2 ACU Description
The 2U ACU chassis houses all of the analog and digital audio IO, DSP processing, and
control IO. The audio signal processor is a 1GHz 32 bit floating point unit which allows for
highly accurate and low latency signal processing. 2GB of DDR2 ram allows for ample sync
delay across 24 channels at sample rates up to 192kHz. Audio routing, AES and ADAT encoding
and decoding is handled by an Artix-7 FPGA. The system is managed by an ARM Cortex-A15
processor running embedded Linux.
The m908 system clock is based on our 4th generation s-Lock PLL technology. This is an
incredibly low jitter PLL that provides exceptional ADC and DAC sample clocking accuracy.
The Audio and Clock flow is shown in the simplified block diagram below.
Page 6 of 135
