Owner`s manual

M+S WIDTH
100m
70m
30s
30m
70s
50m
50s
GRACE DESIGN USA
m201microphone preamplifier
HI-Z
1
48V
HI-Z
130V
ribbon
(
+10dB
)
20
30
40
50
60
INPUT MODE
+48V - 20dB
HI-Z
2
48V
HI-Z
130V
ribbon
(
+10dB
)
20
30
40
50
60
INPUT MODE
+48V - 20dB
1
2
76
5
4
3
8
9
grace design m201
owner’s manual
4
Front Panel Controls
1. 24 position gold contact gain switch
Each gain control has 24 positions and adjusts the
voltage gain from 18dB to 64dB in 2dB steps. In
ribbon mode the gain range is 28dB to 74dB in 2dB
steps.
2. bi-color LED peak indicator
The LED peak indicator, which monitors the output
signal level, turns green at -14dB and switches to
red at +16dB (12dB before clipping). The threshold
level for peak indication is adjustable on each chan-
nel (see the calibration section of this manual).
3. input mode switch
The input mode switch is used to select between
the various types of inputs available with the m201,
including standard 48V, ribbon mic mode, HI-Z, or
the optional 130V DPA™ inputs. Refer to the m201
block diagram at the end of this manual for signal
routing details.
4. 48V phantom power switch
The phantom power switch (labeled +48V) connects
the +48V power supply to pins 2 and 3 on the XLR
input connector. This switch illuminates red. It
should be noted that the LED in this switch actually
monitors the phantom power voltage at the input.
With no microphone connected, the LED will contin-
ue to illuminate for approximately 10 seconds after
the phantom power is turned off as the filter capaci-
tors discharge. As well, even if the phantom power
is switched off, the LED will illuminate if voltage is
being fed from an external source. (i.e. when us-
ing a direct split in a remote recording application.)
Also, the +48V switch is used to activate the +130V
DPA™ mic power if this option is installed.
5. polarity reversal switch
The polarity reverse switch reverses the absolute
phase of the music signal at the input of the pream-
plifier. The switch illuminates green and provides
power for a sealed gold contact relay located on
the preamplifier circuit board. This eliminates signal
wiring to the front panel and switch contact perfor-
mance problems. The polarity reverse function is
active for all input connectors.
6. -20dB pad switch
The 20dB attenuator switch attenuates the input
signal 20dB. The switch illuminates amber when
engaged. Like the phase reverse switch, this switch
controls a sealed gold contact relay on the pream-
plifier circuit board. With the -20 switch engaged,
the effective gain range becomes -2dB to 44dB. The
20dB attenuator is active for 48V Phantom, ribbon
and (optional) DPA inputs. It does not affect the
HI-Z inputs.
7. HI-Z input
This 1/4 inch TRS input is active when the input
mode switch is in the HI-Z position. Suitable for any
high impedance source such as: bass guitar, acoustic
guitar, electric guitar, keyboards, etc... This input is
can be used balanced with a TRS connector or un-
balanced with a TS connector.
8. M-S width control
This knob controls the ratio between the Mid and
Side signals in an M-S recording setup. Please see
the ‘preamplifier operation’ section of this manual
for complete information regarding this feature.
9. standby / power switch
Connects the mains voltage and turns on the
m201When depressed the pushbutton will illumi-
nate green and the preamplifier will be on. When
released the preamplifier will be in standby mode.