BOUNDARY CONTROL:
POSITION CONTROL:
Reflective boundaries, such as floors, walls, even table tops, reinforce a speaker’s low frequency output. Conversely,
placing speakers out into a room decreases bass response. The highest low frequency output is with the BOUNDARY
control in the “0” position, which assumes no significant boundary reinforcement is present. Each control step
attenuates low frequencies by 1.5 dB (at 50 Hz), with rapidly decreasing effect above 300 Hz. Refer to the diagram
in Fig. 6 for information on setting the control appropriately.
Near-field monitoring reduces the effect of room acoustics on the signal, and provides greater sonic detail. Mid and far
field monitoring conversely reveal aspects of recorded ambience and are more representative of end use. With that
increased listening distance, though, a speaker’s upper frequency power response attenuates due to room influences and
air absorption. The C-20 may be adjusted to compensate for this change, and provide flat response at various listening
distances. Setting the control in the“FF” (far-field) position gives the maximum high frequency output. Each step
counter clockwise (moving toward the near-field position) attenuates the 20 kHz by an additional .75 dB with the
effect rolling off at 3 kHz. See Fig. 7 for appropriate POSITION control settings for various listening distances.
0
2
1
0
2
1
0
2
1
0
2
1
BOUNDARY
BOUNDARY
BOUNDARY
BOUNDARY
BOUNDARY
0
2
1
Quarter Space
Quarter/Half Space
Half Space
Half/Whole Space
Whole Space
Fig. 6. Boundary Control Settings Diagram
1 M
0’
1.5M
2M
2.5M
3M
Near-field
Mid-field
Listener Distance
C-20
Monitor
Far-Field
POSITION
FF
NF
MF
POSITION
FF
NF
MF
POSITION
FF
NF
MF
POSITION
FF
NF
MF
POSITION
FF
NF
MF
Fig. 7. Position Control Settings Diagram
