Yamaha PROFESSIONAL Q1027 User manual

YAMAHA
PROFESSIONAL
SERIES
GRAPHIC EQUALIZER
Q1027
OWNER’S MANUAL
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MR nu m
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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.

EQUALIZING
This model divides the audible frequency 40Hz—16kHz by 1/3 octaves into 27 portions to enable extremely intricate
compensation. Equalizing can be provided from the twin aspects of indoor transmission response and howl, and it is
possible to improve the sound quality at the audience seats by making the indoor transmission response flat, and also tc
provide a sufficient howl respite for microphones used on the stage.
e Equalizing for correct indoor response
The frequency response curves and specifications
provided with speaker units and systems are derived
from measurements taken in an “anechoic chamber”
(an acoustically "dead" room in which no reflection of
sound takes place). When used in a real listening
environment such as a hall or club, however, the actual
percieved response is highly dependent on the acoustic
properties of the listening area. Hard surfaces such as
windows, wood panelling and tile floors can reflect the
high frequencies causing a "tinny" or "ringing" sound,
while curtains, chairs and even people can absorb high
frequencies causing a "flat" or “muddy” response. It is
therefore essential that the sound reinforcement
system be properly equalized to compensate for the
PINK NOISE
GENERATOR
e Equalizing to combat howl
Depending on the acoustics of a hall or room, howl is
sometimes heard at a specific frequency. In a case like
this, howl can be prevented by reducing the gain only
for that frequency where the howl is generated. For
accurate equalizing, a pink noise generator and a real
time analyzer are useful, Set the microphone on the
stage, connect the pink noise generator to the auxiliary
input of the PA console mixer and the real time
REAL TIME
ANALYZER
PINK NOISE
GENERATOR
specific acoustic conditions in the area where it is to be
used. In order to improve the sound quality at the
listening position, it is necessary to perform equalizing
of the indoor transmission response.
For this kind of equalizing, a pink noise generator and
a real time analyzer must be provided as measuring
instruments.
Connect the pink noise generator to the PA console
mixer and the pink noise is then heard through the
speaker. Use the real time analyzer in the service area
to measure this noise and adjust the controls on the
graphic equalizer so that the indicated transmission
response is made flat,
SPEAKER
REAL TIME
ANALYZER
analyzer to the auxiliary output, and then increase the
gain. Use the controls on the graphic equalizer to
adjust the gain of the frequency where the howl is
generated, and if as a result howl is generated at almost
every frequency when the gain is increased, it means
that the problem of the howl at the original frequency
has been resolved.
SPEAKER
With compensation using only measuring instruments, the sound is sometimes found to be lacking, and after performing
equalizing from the twin aspects of the indoor transmission response and howl, check the sound quality and level
balance in the service area by ear, and perform overall adjustment.

MOUNTING THE SECURITY COVER ΘΖ SPECIFICATIONS
Mounting the security cover
If the control knobs on the equalizer, once set, are moved by mistake or carelessly when the model is
being used in one location only, the controls have to be re-adjusted.
To prevent this kind of trouble, a security cover is provided as an accessory to this model.
Remove the four setscrews of the front panel and then mount the cover using the mounting screws.
Setscrews Setscrews
n
:
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ΠΤ
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deii
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=3
=
Front
panel
Mounting
Screw
Security cover
(1) Remove the setscrews of the (2)Mount the accessory cover (3) Mount the security cover in
front panel, mounting screws in place of line with the mounting screws.
the front panel's setscrews. |
SPECIFICATIONS
Frequency Response PHONE JACK 20Hz ~ 20kHz (0 + 0.5dB)
XLR 20Hz ~ 20kHz (0 + 1.5dB)
Total Harmonic Distortion PHONE JACK less than 0.02% (20Hz ~ 20kHz)
XLR less than 0.5% (20Hz ^ 20kHz)
*Hum & Noise —100dB (EQ flat, 600 2 load)
Gain OdB (EQ by-pass)
Maximum Output Level +24dB (600 Ω load)
Center Frequencies 40, 50, 63, 80, 100, 125, 160, 200, 250, 315, 400, 500, 630, 800
1k, 1.25k, 1.6k, 2k, 2.5k, 3.15k, 4k, 5k, 6.3k, 8k, 10k, 12.5k,
16k(Hz)
Frequency Accuracy Less than +5%
Range of Boost/Cut Boost 0 ~ +12dB, Cut 0 ~ —12dB
High Pass Filter 18dB/oct 40Hz + 10%, 80Hz + 10%
Input Impedance PHONE JACK 10kX2 (unbalanced)
XLR 8kQ (balanced)
Output Impedance PHONE JACK 40 Q (unbalanced)
XLR 40 Q (balanced)
Power Source U.S. & Canadian Models 120V AC 60Hz
General Models 110-130 or 220-240AC Selectable, 50/60Hz
Power Consumption U.S. Model 18W
Canadian Model 24VA
General Models 20W
Dimensions (W x D x H) 480 x 305 x 95.5 mm (18-7/8" x 12" x 3-3/4")
(When security cover mounted 480 x 318 x 95,5 mm,
18-7/8" x 12-1/2" x 3-3/4")
Weight 8 kg (17.6 Ibs)
* Measured with —6 dB/oct filter @12.47kHz equivalent to a 20kHz filter with infinite dB/oct attenuation.
€ OdB is referenced to 0.775 V r.m.s.
Specifications subject to change without notice,

ᾳ
NIPPON GAKKI CO, LED HAMAMAT SH, JAPAN
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jomp-10] 821005 FF
—— ——————ÉVEIOUR —_e A Ee) SOE o
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Printed E uy Japan
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