Yamaha PROFESSIONAL Q1027 User manual

YAMAHA
PROFESSIONAL
SERIES
GRAPHIC EQUALIZER
Q1027
OWNER’S MANUAL
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MR nu m
Er id
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FEATURES / CAUTION
The Q1027 is a professional-grade 27-band graphic equalizer that offers top-quality performance, features, reliability
and durability. It is perfectly suited to a wide range of professional applications including concert sound reinforcement
and studio recording.
Please be sure to read this operation manual carefully in order to make the most of your Q1027's extensive perform-
ance capabilities.
FEATURES
ΦΑΙ! inputs and outputs feature Phase Switches, Ground
Switches and cannon connectors, Rack-mountable
configuration. Rugged to withstand the rigors of profes-
sional use. Human-engineered control layout for fast,
error-free operation. Elegant styling. Exceptionally high
S/N ratio and low distortion.
@27 1/3-octave equalizer bands provide extremely fine
control capability. Unique “L” integrated circuit
construction effectively minimizes inductive noise pick-
up maintaining excellent signal-to-noise ratio and low
distortion.
@Equalizer bypass switch, 40/80 Hz high-pass filter
selector, accurate input attenuator and peak level indica-
tor all add up to more convenient, more precise sound
control. Removable security cover prevents accidental
alteration of settings in studio and sound reinforcement
applications. Designed for optimum “in-use” flexibility
and performance.
CONTENTS
ΕΕΑΤΥΒΕΒ/ΘΑΌΤΙΟΝ.................. 2
FRONT PANEL OPERATION ............. 3
CONNECTION/BLOCK DIAGRAM.......... 4
REAR PANEL OPERATION .............. 5
ΕΩΙΑΙΙΖΙΝα........................ 6
MOUNTING THE SECURITY
COVER/SPECIFICATIONS ............... 7
CAUTION
@Locate the Q1027 out of the direct rays of the sun,
avoiding locations subject to vibration and excessive
dust, heat, cold or moisture.
@When displacing the instruments, be sure to disconnect
the power supply cord and every connecting cord to
prevent their breakage and short,
eDo not attempt to clean any accumulations of dirt
with chemical solvents (such as alcohol or benzene).
Wipe only with a clean completely dry cloth.
€ Keep this manual in a safe place for future reference,
and refer to it frequently until you are fully familiar
with your Q1027.
e This model is designed to be mounted on 19" standard
rack.
e Voltage Selector switch on the rear of the O1027 must
be set for your local mains voltage BEFORE plugging
in the AC main supply. Voltages are 110-130 or
220-240AC, 50/60Hz. U.S. and Canadian models are
not provided with the voltage selector.

FRONT PANEL OPERATION
ΕΠ RENI
@ POWER switch
When this switch is depressed to the ON position, the
power is supplied to the equalizer and the indicator
lights. Depress the switch again to set it to the OFF
position,
* Between three and five seconds after the switch has
been set to ON, the muting circuit is activated in
order to suppress the pop noise, produced when the
power is initially supplied, and there are no output
signals.
O Equalizer section
Available in this section are the control knobs which are
used to increase or reduce the center frequency level of
the frequencies in the audible band which is divided into
27 parts. Based on a reference value of O dB, the level
may be varied up to a maximum of +12 dB. To set the
level, align the red line of the knob with the setting
scale.
Red line
E El E El El == EJ E
RESPONSE (48)
RESPONSE (dB)
ΤΗΕ:
FREQUENCY (Hz)
O PEAK indicator
This lights when the output level exceeds +21 dB and it
warns that the output level is excessively high.
OINPUT Attenuator
This
is
used
to
adjust
the
input
level.
When
rotated
in
the
counterclockwise
direction,
it is
possible
to
attenu-
ate
the
level
in
1
dB
steps
down
to
—20
dB.
At
the
co
position,
the
input
signals
are
cut
off
entirely
and
there
is
no
sound,
When
the
overall
level
has
risen
due
to
equalizing,
take
steps
to
turn
down
the
input
level
by
a
value
equivalent
to
the
rise
in
the
level
and
eliminate
the
difference
in
level
caused
by
the
presence
or
absence
of
equalizing.
*
The
attenuator
does
not
work
when
the
EQ
switch
is
set to the OUT position.
O EO (equalizer bypass) switch
This switch isolates the equalizer section and passes the
input signals to the output. When the knob is set to IN,
the indicator light to indicate that the equalizer section
is now working. When it is set to OUT, the indicator
goes off, and the input signals bypass the INPUT ATT
contro! and the equalizer section, and they are sent
straight to the output. In cases like this, the Q1027
functions as a buffer amplifier, and the EQ switch is
used to compare the sound quality with and without
equalizing.
INPUT
T
oyr
OUTPUT
QHPF (high-pass filter) switch
This
filter
has
a
slope
response
of
18
dB/oct
and
its
switch
allows
selection
between
a
cutoff
frequency
of
40Hz
and
80Hz.
At
the
"40"
position,
signals
with
a
frequency
of
less
than
40Hz
are
attenuated,
and
it
is
possible
to
suppress
the
low-frequency
standing
waves
(low-frequency
resonance)
produced
in
studios
and
small
rooms,
to
eliminate
the
muddiness
in
the
low
range
and
to
obtain
a
clear-cut
sound,
At
the
'"'80"
position,
signals
with
a
frequency
of
less
than
80Hz
are
attenuated,
and
it
is
possible
to
reduce
the
"fuzziness''
of
vocal
microphones
and
the
hum
and
noise
of
electrical
musical
instruments,
etc.
The indicator light when the switch is set to the "40"
and “80” position.
FREQUENCY
RESPONSE
®— Indicator

CONNECTION BLOCK DIAGRAM
CONNECTION
MIXER(PRE. AMPLIFIER)
ΒΙΣΙΕΙΦΙΣΙΣ
SOURCE
SPEAKER
[ BLOCK DIAGRAM
9
[A era
ATT
[INPUT] d , i----- g-----Z
ET 40Hz 800Hz Ι6ΚΗΣ
(se >
L- 27 BANO —
ON o OFF
PIN 1 GND SW
OFF
o
FUSE
σ ο
€) LED

REAR PANEL OPERATION
| O YAMAHA
| ΠΠ SER NO
|
PATENI PENDING
@ OUTPUT O Cannon socket XLR-3-32
It is provided with a Cannon socket for balanced output The Q1027 employs a 3-pin (pin 1 shielded ground, pin
applications and a phone jack for unbalanced output 2 hot, pin 3 cold) socket for connection,
applications, The output impedance in either case is 40 Compatible plugs include the Cannon XLR-3-11C and
ohms, the Switchcraft A-3-F.
* The phone jack output takes priority when both the
Cannon socket and phone jack are connected @Cannon socket XLR-3-31
simultaneously. Compatible plugs include the Cannon XLR-3-12C and
the Switchcraft A-3-M,
@ OUTPUT PHASE switch
This switch selects the phase of the balanced output. Set @ Phone jacks
to the “N” side to match the phases of the input and These employ standard plugs.
output and to the “R” side for reverse phase,
The switch is used for phase alignment when many O Fuse
components have been connected or when the phase Always use a fuse with the same ratings of the existing
changes in accordance with the setting position of the one for replacement purposes.
speaker system.
* The phase of the phone jack side cannot be selected. O VOLTAGE SELECTOR (General Models Only)
Set this to your local AC mains voltage. Failure to do so
© INPUT will result in seriously impaired performance or even
It is provided with a Cannon socket for balanced input severe damage.
applications and a phone jack for unbalanced input
applications. The input impedance is 8 kiloohms for the
balanced input and 10 kiloohms for the unbalanced
input.
* The phone jack input takes priority when both the
Cannon socket and phone jack are connected
simultaneously,
OPIN 1 GND switch
This switch sets the balanced output ground line (pin 1
shielded ground) to ON and OFF.
Hum or noise is sometimes caused by the illumination
inside the hall and the high-power components when
signal cables are used extendedly or when they are used
in a certain placement to connect a number of compo-
nents. This noise can sometimes be reduced by isolating
the ground line, In a case like this, use this switch.