TL Audio VTC - Manual (Page 48)

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foldback mixing from both channel and MixB paths on the input modules.
The sources for headphones 1 are mixed by IC2A and IC2B, and then controlled by the level pot
RV1. The headphone outputs are directly driven by the high drive TLE2062 at IC1A and IC1B.
These devices will directly drive headphones of 32ohms or higher impedance. The outputs are passed
down to PC355 and out via the jacksocket PCB or patchbay.
The headphone signals may also be monitored in the control room, by routing to the PFL sub-mix on
PC349 (SW1 for headphones 1). In this case, the Control Room source selector switch, SW2, is over-
ridden to prevent a circular signal path being created.
The above description quotes circuit references for headphones 1, the circuit for headphones 2 is
similar.
4.11. Solo System.
The block diagram of the console solo system is shown in fig. 5.
The console has three modes of operation:
PFL (Pre-Fade Listen):
The default mode for Channels and MixB paths on the
input modules.
AFL (After-Fade Listen):
From the Groups, Aux Masters and Stereo Returns.
SOLO IN PLACE:
Replaces PFL mode on Channels and MixB, when selected
on the Master Module. Channels and MixB paths not in solo
mode are muted.
There is a separate AFL/PFL stereo mix buss, which replaces the normal Control Room output when
any PFL or AFL switch is activated. All other outputs from the console remain unchanged in this
mode. PFL/AFL active is signalled by a red LED adjacent to the active switch, and by the yellow
LED on the Master Module VU meter panel.
If Solo In Place mode is selected by the switch on the lower master module, any Channel or MixB
path solo switch that is activated will cause all of the other Channel and MixB paths to be muted. In
this mode, the Control Room output does not switch over to the AFL/PFL buss, and the yellow LED
is not illuminated. Operators should be aware that Solo In Place causes other signal paths to mute,
thereby cutting the console outputs to the recorder, etc. and programme material may be lost.
A combination of Solo In Place and AFL is possible. This occurs if Solo In Place mode is selected,
and a Channel or MixB path solo switch is active, followed by activation of an AFL switch on a
Group, Aux Send or Stereo Return. Under these circumstances, the unselected Channel and MixB
paths will still be muted, but the Control Room output will switch to the AFL/PFL buss and the
yellow LED will illuminate. This combination of modes allows, for example, the aux send or effects
return contribution of a single channel to be listened to in the Control Room.
The PFL buss from the input modules is connected along the backplanes PC337 to the front Master
backplane, PC336. The PFL mix amplifiers are shown on CD1336 sheet 5. Connectors CN5 and CN6
link the PFL buss to the input bays, whilst CN4 connects to the Group Modules on the lower Master
Module front panel. Note that the input module section of the buss is routed via the switches IC22
and IC23, which prevent channel PFL signals reaching the Control Room output when in the
combined Solo In Place - AFL mode described above. The mixed signals “PFL L” and “PFL R” are