Arcam Preamp Processor AV8 - Manual (Page 80)

AV8 Audio Board
Introduction
This board forms part of the AV8 Preamp Processor, it performs analogue input selection and routing of analogue
signals to the various outputs. There are four sets of outputs; main, zone2 and two tape loops “Tape” and ”VCR”.
Main and zone2 outputs have volume controls (either of which can be the source for the on-board headphone
amplifier). A gain ranging stage in the middle of the audio path sets the headroom of the signal chain and also
provides a feed to the A-D converter on the digital board.
Control of the board is via the host micro-controller on the digital board.
BLOCK DIAGRAM
2
2
2
2
2
2
2
2
2
2
2
Input Mu
x
Record loop buffers
Volume
Volume
Volume
Gain range
Mute
Mute
Headphone select
Mute
ZONE2
MAIN L/R
Surround/
Centre/
Sub outs
Headphone
Stereo inpu
ts
Internal DAC L/R
External SACD input L/R
Internal DAC Surround
/Centre / Sub channel inputs
External SACD Surround
/Centre / Sub channel inputs
Tape out
VCR out
Headphone amp
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
6
6
6
6
Multichannel Mux
To ADC
Key:
n
Signal bus where n is the number of audio channels