Technical specification, Tr oubleshooting – Joemeek three Q Desktop Channel User Manual
Page 8

15
Technical
Specification
Input
impedances
Mic:
1.2kohm;
Line:
20kohm
Pre-amp
overall
gain
0dB
to
60dB
Common
mode
rejection
70dB
Equivalent
input
noise
-128.5dBu
(unweighted)
Distortion
0.001%
(below
Compressor
threshold)
Frequency
response
10Hz
to
70kHz
(-3dB)
Maximum
input
before
clipping
Mic:
+19.5dBu;
Line:
+44.5dBu
Headroom
before
clipping
+19.5dBu
Compressor
threshold
-6dBu
to
+20dBu
(variable)
Compressor
ratio
5:1
(typical)
Compressor
attack
time
1
msec
to
100
msec
(adaptive)
Compressor
release
time
0.1
sec
to
3
sec
(adaptive)
Nominal
output
levels
+4dBu/-10dBv
Output
impedance
75ohm
Output
Level
switch
12dB
attenuation
Noise
Floor
-85dBu
(typical,
with
~40dB
mic
gain)
VU
Meter
8
segment
bargraph
Power
supply
12V
ac
mains
adaptor
Power
consumption
12W
Mechanical
220W
x
44H
x
180D
(overall)
W
eight
1
kilo
14
Tr
oubleshooting
1)
No
Power
(no
lights
work)
•
Is
the
power
supply
plugged
in
(both
ends)?
•
Is
the
mains
power
on?
2)
The
microphone
doesn’t
work
•
Is
it
connected
to
the
correct
(XLR)
input
on
the
rear
panel?
•
If
it
is
a
condenser
microphone,
is
the
phantom
power
switched
on?
•
Is
the
‘Line’
switch
out
(LED
of
f)?
•
Is
the
‘Input
Gain’
control
turned
up?
•
Is
the
‘Output
Gain’
control
turned
up?
3) The line input doesn’t work
• Is the source connected to the correct (jack) input on the back of the unit?
• Is the ‘Line’
switch in (LED on)?
• Is the ‘Input Gain’
control turned up?
• Is the ‘Output Gain’
control turned up?
4) The compressor doesn’t work
• Is the ‘Comp’
switch in (LED on)?
• Is the ‘Compress’
control turned up enough?
• Is there enough signal, as set by the ‘Input Gain’
control, to drive the
compressor?
5) T
oo little or too much compression
•
T
urn the ‘Input Gain’
control up or down respectively
, to adjust the
signal level to the compressor
6) The Meequalizer doesn’t ‘t work.
• Is the ‘EQ’
switch in (LED on)?
• Is ‘Input Gain’
control turned up?
• Is ‘Output Gain’
control turned up?
7) T
oo much noise
• Is the ‘Input Gain’
control too high?
T
ry moving the mic closer to the
source
• Is the ‘Output Gain’
control too high (eg: when lots of compression is
being used)?
• Is there too much EQ boost?
• Is the noise already present in the input signal? (T
ry removing the
input)
8) Sounds distorted
• Is the ‘Input Gain’
control too high?
• Is the ‘Output Gain’
control too high?
• Is there too much EQ boost?
• When using the compressor
, is the Release control set too low?
three q manual.indd
3/9/04, 4:19 PM
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