Operation Manual

REL Acoustics ‘ST III’ User Manual
8
Control Panel
The layout of the panel is intended to ensure total ease of use. You can use any input in
combination with any other. This means that both low and high level inputs can be used
concurrently. Individual volume controls for the high and low level inputs ensure precise
individual adjustment for both two channel (stereo) signals and multi-channel (surround
sound) signals.
The mode switch allows both the phase and the filter bypass to be incorporated into one
control. The Line positions route the low level signals through the ABC filter circuits. In the
LFE (Low Frequency Effects) positions the low level signals bypass this filter. This is to
ensure compatibility with multi-channel Home Theatre surround sound systems where the
bass frequency range is controlled within the software by the decoder circuitry. The high level
inputs are always routed through the ABC.
The phase can be reversed by 180 degrees by means of this same switch to preserve the
relative phase between your main system and the REL. This acts at both High Level and Line
Level. See table below.
MODE SELECTOR
SOURCE PHASE
1 LINE 0
2 LFE 0
3 LINE 180 DEG
4 LFE 180 DEG
The two filter controls are to allow coarse and fine control of the filter settings. The coarse
control marked A through D changes the turnover frequency by approximately half an octave
per division. The fine control marked 1 through 6 offers a resolution of approximately one
semitone per division.
The frequencies offered by these two controls are shown in the table below:
ROLLOFF FREQUENCY HERTZ
1 2 3 4 5 6
A 22 23 25 27 28 30
B 32 34 36 38 41 43
C 46 49 53 56 60 64
D 69 73 78 83 89 95
These frequencies are within 1% tolerance and are repeatable between all ST range models.