Yamaha Q2031B User manual

YAMAHA
GRAPHIC EQUALIZER
_ EGALISEUR GRAPHIQUE
GRAPHISCHER EQUALIZER
ECUALIZADOR GRAFICO
02031B
GO1031C
GO2015A
OPERATION MANUAL `
MANUEL
D'INSTRUCTIONS
... BEDIENUNGSANLEITUNG
MANUAL DE INSTRUCCIONES

PRECAUTIONS
1. Avoid Excessive Heat, Humidity, Dust and 4. Make Sure Power Is Off Before Making Or
Vibration | Removing Connections
Keep the unit away from locations where it 15 likely to be Always turn the power OFF prior to connecting or discon-
exposed to high temperatures or humidity — such as near ' necting cables. This is important to prevent damage to the
radiators, stoves, etc. Also avoid locations which are subject unit itself as well as other connected equipment.
to excessive dust accumulation or vibration which could cause | |
mechanical damage. | 5. Handle Cables Carefully
| Always plug and unplug cables — including the АС cord —
2. Avoid Physical Shocks by gripping the connector, not the cord.
Strong physical shocks to the unit can cause damage. Handle
it with care. 6. Clean With a Soft Dry Cloth
- Never use solvents such as benzine or thinner to clean the
3. Do Not Open The Case Or Attempt Repairs unit. Wipe clean with a soft, dry cloth.
Or Modifications Yourself |
This product contains no user-serviceable parts. Refer all 7. Always Use the Correct Power Supply
maintenance to qualified Yamaha service personnel. Open-
ing the case and/or tampering with the internal circuitry will
void the warranty.
Make sure that the power supply voltage specified on the
rear panel matches your local AC mains supply. Also make
sure that the AC mains supply can deliver more than enough
current to handle all equipment used in your system.
IMPORTANT NOTICE FOR THE UNITED KINGDOM
Connecting the Plug and Cord
IMPORTANT. The wires in this mains lead are coloured in accordance with the fol-
lowing code:
BLUE : NEUTRAL `
BROWN =: LIVE
As the colours of the wires in the mains lead of this apparatus may not correspond
- with the coloured markings identifying the terminals in your plug proceed as follows:
The wire which is coloured BLUE must be connected to the terminal which is marked
_ with the letter М or coloured BLACK.
The wire which is coloured BROWN must be connected to the terminal which is marked
with the letter L or coloured RED.
Making sure that neither core is connected to.the earth terminal of the three pin plug.
* This applies only to products distributed by YAMAHA - KEMBLE MUSIC (U.K.) LTD.

FEATURES
Ф The two-channel system offers completely independent chan-
nel control — from the input all the way to the output. (02031В,
GQ2015A) |
€ The Q2031B/GQ1031C offers a narrow, 1/3-octave bandwidth
and 31-band control over the entire 20 Hz to 20 kHz range for
very precise equalization.
@ The 1U-size GQ2015A offers 15-band control on two inde-
pendent channels.
€ Equipped with an EQ switch that bypasses the equalizer sec-
tion, a RANGE, switch that changes the equalization range
and a host of other features the equalizer presents itself as a
unit carefully designed from both functional and operational
perspectives.
O The Q2031B features a high pass filter that allows setting the
rolloff frequency using a slider, and the GQ1031C/GQ2015A
is equipped with an 80 Hz high pass filter.
е Equipped with transformerless balanced XLR-type and phone
jack input and output connectors.
e Suitable for PA and recording applications and a variety of
other uses.
Ө Can be mounted in a standard 19" rack.
|
CONTENTS
FRONT PANEL...................................... ... 3
REAR РАМЕ1.......................................... 5
TYPICAL CONFIGURATIONS ............................ 6
` ACOUSTIC CONTROL ........... ....................... 7
SPECIFICATIONS...... e 8
BLOCK ПІАОВАМ...................................... 9
.......................................... 9
DIMENSIONS

FRONT PANEL
Q2031B
y
+
оа
ео
Ca
cy
а
Wk 125к 16k 20% Hz
Bk вак 5k ак
CHANNEL В
25k 35k 2k
125k 1.8%
1k
CHANNEL B
8 ü 8
8
160 200 250 915
з æ 19 125
CHANNEL A
50 H
GQ1031C
CO sess,
GQ2015A

FRONT PANEL
© POWER switch
When this switch is pressed to turn the power on, the POWER
indicator LED above the switch will light.
* To prevent click noise, the output is muted for approximately
two seconds after the power.is turned оп.
RANGE switch
Allows selection of the boost or cut range for equalization.
When this switch is off, the maximum range of +/-12 dB is
selected; when on, the +/-6 dB range is selected. Use this
_ switch to select the range suitable for each application. When
the switch is on, the LED indicator to its left lights to show
that the +/-6 dB range is in effect.
Ө HPF switch (Q2031B)
/80 switch (GQ1031C/GQ2015A)
Allows switching the high pass filter in or out of the audio
path. When the switch is on, the high pass filter is effective
and the indicator LED lights. The Q2031B provides 12 dB
per octave rolloff below the frequency set with the HPF con-
trol ©, while on the GQ1031C/GQ2015A the rolloff is 12 dB
per cotave below 80 Hz.
When the switch is off, the input signal goes directly to the
equalizer section, bypassing the HPF.
On the GQ2015A the /80 switch turns the HPF on/off for
channels À and B simultaneously.
O EQ switch
This switch determines whether the signal із routed through
or bypasses the equalizer section. When the switch is off,
the equalizer is bypassed and the settings of the equalizer
controls @ are ineffective, providing a flat frequency re-
sponse. When the switch is оп, its indicator lights and the
equalizer is switched into the audio path. The equalized sig-
nal can be compared with the un-equalized signal simply by
alternately turning the EQ switch on and off. |
Q LEVEL control
Allows precise control of the optimum input sensitivity. When
the control is at the top of the scale, the input level remains
unchanged (+4 dB).
This control can be used to restore the output level when the
overall level has been changed during the equalization pro-
cess. This, however, will also change the input level. Equal- `
ization methods which do not change the LEVEL. control set-
ting will yield a better signal-to-noise ratio and wider dynamic
range.
Example: The settings in Fig. A will provide a better result
than the settings in Fig. B.
€ Boost/cut settings centered around the 0 dB point
Q HPF control (Q2031B)
The HPF control sets the rolloff frequency for the built-in high
pass filter. The control allows continuous adjustment over
the range of 20 Hz to 200 Hz. Below the selected frequency
there will be a 12 dB per octave cut.
The filter is turned on/off using the HPF switch Ө.
The HPF can be adjusted to eliminate low-range standing
waves, a resonance phenomenon that sometimes occurs in
small indoor environments, vocal "pops" and wind noise in
microphones and AC hum.
GQ1031C
Q2031B
Min. GQ2015A
Response [dB]
~;

FRONT PANEL
O Equalizer controls
Q2031B/GQ1031C :
The 20 Hz to 20 kHz spectrum is divided into 31 bands
(1/3 octave steps), and each of these bands is equipped
with an equalizer control that allows boosting/cutting the
corresponding center frequency.
GQ2015A :
The 25 Hz to 16 kHz spectrum is divided into 15 bands
(2/8 octave steps), and each of these bands is equipped
with an equalizer control that allows boosting/cutting the
corresponding center frequency.
The scales on either side of the controls are calibrated to indicate
the correct setting values when the RANGE switch is off (+/-12 dB
range). When the RANGE switch is on (+/-6 dB range), the true
values are one-half of the calibrated values.
Q2031B, GQ1031C
Response [dB]
415
х | AAAAANAR A AAA AAA à AAAI ANNA anA
IAN AU RINA AAA НАЈ AA O
САХ
|
4
5
ЫЗЫ Се АРКАН
XXIX MA РО
K ХХХ уф POSE ХҚ ИМ
, А ОУ
>
| ST YU
AAA
10 10k
Frequency H iz
GQ2015A . |
Response [dB]
+15
„AARIA ANA ALA]
| А МАХХАХМАКХКХА.
"A УБА Бе СР У SES
III СЫЯ ka]
JL XXX X KXK КАА
| Г МУ УМУМ УМ HI
10 100 10k 30k
Freq џепсу Ha
d
р
To get the best performance from your equalizer, it is important
that you understand the frequency components that make up the
sounds of each musical instrument. The following graph is pro- `
vided to aid this understanding.
You should also bear in mind, that besides fundamental frequen-
cies harmonics also can have a significant impact on timbre.
10k 20k
20 50 100 200 500 1к 2k 5k
FREQUENCY (Hz)
O SIGNAL and PEAK indicators
This SIGNAL indicator LED lights up when the output signal
level is within 13 dB below nominal level. The indicator con-
firms that the current signal level settings are suitable.
The PEAK indicator LED lights up when the output signal
level reaches 3 dB below clipping level. If the PEAK indica-
tor LED lights continuously, the overall level is too high and
must be reduced using one of the two following methods:
(1) By reducing the overall level with the LEVEL control
(2) By reducing the levels of each equalizer band

REAR PANEL
Q2031B OUTPUT +4dB
CHANNEL B
GQ1031C
GQ2015A
CHANNEL BICHANNEL A
O INPUT connectors
The equalizer is equipped with balanced XLR-type and 1/4"
phone jack input connectors. For both a 600 © line should
be used. The rated input level is +4 dB.
O XLR-3-31 type connector
Pin 2 : Hot (+) Pin 1 : Ground
Pin 3: Cold (-)
O TRS phone connector
Tip : Hot (+)
Sleeve
:
Ground
:
Ring
:
Cold
(-)
INPUT +498
O OUTPUT connectors
The equalizer is equipped with balanced XLR-type and 1/4"
phone jack output connectors. For both a line with the match-
ing load impedance of 600 Q should be used. The rated out-
put level is +4 dB.
® XLR-3-32 type connector
Pin 1 : Ground Pin 2 : Hot (+)
Pin 3: Cold (~)

TYPICAL CONFIGURATIONS
O Insertion between the channel (master) insert out/in
MIXING CONSOLE
INSERT OUT
INSERT IN
Q2031B
GQ1031C X 2
GQ2015A
INPUT
OUTPUT
POWER AMP
SPEAKERS
POWER AMP
O Insertion in the main line of the output system
MIXING CONSOLE
OUTPUT L
OUTPUT В
POWER AMP
Q2031B
GQ1031C X 2
GQ2015A
POWER AMP

ACOUSTIC CONTROL
The diagrams show the connection method for the Q2031B. The GQ2015A is connected in the same way. In case
of the GQ1031C you will need two units for a two-channel setup.
O Maintaining Ideal Indoor Propagation Characteristics
Speaker systems that demonstrate flat responses in anechoic
rooms may have irregular responses in a concert hall due to
acoustic conditions. The Q2031B equalizer can be used to
minimize these irregularities. |
noise is radiated from the speaker. While measuring the pink
noise at strategic listening positions in the room using the
spectrum analyzer, adjust the Q2031B until the preferred `
response is obtained.
For smoothing of the playback system response a pink noise
generator and a spectrum analyzer are needed. Connect the
pink noise generator to the mixing console so that the pink
PINK NOISE MIXING
GENERATOR CONSOLE
POWER AMP SPEAKER
Q2031B
SPECTRUM
POWER
AMP
SPEAKER
ANALYZER
€ Ensuring Adequate Feedback Margins in Stage Monitor Systems
NOTE : Measuring instruments can only provide basic sound
realism. After you have completed the indoor propaga-
Depending on the room characteristics feedback can result
in howling or ringing being generated at specific frequen-
cies. In such cases the equalizer can be used to reduce lev- tion and feedback compensation adjustments, make the
els at the affected frequencies and thereby to control the final adjustments using the ultimate judge, vour trained
feedback, but a pink noise generator and a spectrum ana- ears.
lyzer are again required.
Set the equipment up just as for an actual performance, and
connect the pink noise generator to a spare input connector
of the mixing console and the spectrum analyzer to a spare
output connector. After ensuring that pink noise is being prop-
erly radiated from all PA speakers and monitor speakers, |
gradually raise the output level until it is evident at which
frequencies feedback will occur. Use the Q2031B to reduce
the levels of these specific frequencies.
Proper adjustment will provide a safety margin against feed-
back when the output level is raised.
A Pink Noise Generator
generates a uniform level of random noise throughout
the audio spectrum. (Equal Energy per octave)
A Spectrum Analyzer
divides the audio spectrum into ranges and indicates
the sound pressure for each range.
SPEAKER
POWER AMP
MIXING CONSOLE
--- = = ~
SPECTRUM
ANALYZER : |
POWER AMP
SPEAKER

SPECIFICATIONS
FREQUENCY RESPONSE 20Hz-20kHz +0.5dB (0 +4dB* 6000
TOTAL
HARMONIC
DISTORTION
Less
than
0.05%
(THD+N),
20
Hz
~
20
kHz
@
+4
dB*
6000,
Equalizer...all
flat
(098)
`
HUM
&
NOISE
—96
dB*
—94
dB*
|
—96
ав*
(Average,
Rs=60002
ВРЕ:
20Hz
~
20kHz)
Equalizer
...
all
flat
(0
dB),
Input
Level
...
Max.
MAXIMUM VOLTAGE GAIN | 0 dB, Input Level ... Max.
EQUALIZER CONTROLS 31 band (1/3 octave)
Center
Frequencies:
20,
25,
31.5,
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, | 400, 630, 1k, 1.6k, 2.5k, 4k,
6.3k, 8k, 10k, 12.5k, 16k, 20kHz 6.3k, 10k, 16kHz
Variable Range: + 12dB / + 6dB |
HIGH PASS FILTER 12dB/octave
(Rolloff Frequency) (20 ~ 200Hz at -3dB point.) 12dB/octave (B0Hz at -3dB point.)
PEAK
LED
INDICATOR
Red
LED
on
each
channel
turns
on
when
post-EQ
signal
reaches
the
level
3
dB
below
clipping.
|
SIGNAL
LED
INDICATOR
Green
LED
on
each
channel
turns
on
when
post-EQ
signal
reaches
the
level
13
dB
below
nominal
level.
POWER
REQUIREMENTS
U.
5.
8
Canadian
Models
`
AC120V,
60Hz
General Model : AC230V, 50Hz
DIMENSIONS (W x H x D) 480 x 93.4 x 280mm 480 x 49.4 x 280mm
WEIGHT | 4.0kg | 2.8kg 3.0kg
* 0 dB is referenced to 0.775V RMS.
15 band (2/3 octave)
25, 40, 63, 100, 160, 250,
O INPUT SPECIFICATIONS
Input Level
Nominal
Level
Maximum
Connectors
«+
omina!
Level
[Before
Clipping
+4
dB
(1.23V)
|
+4
dB
(1.23V)
|
+24
dB
(12.3V)
XLR-3-31
Type
Phone Jack (TRS)
INPUT
Connectors
Source
Impedance
Input
Impedance
INPUT 600 ©
(A, B) | вю DI
O OUTPUT SPECIFICATIONS
- Output Level
А Maximum
Nominal Level | Before Clipping
OUTPUT . XLR-3-32 Type
(A,
B)
150
Q
600
Q
Lines
+4
dB
(1.23V)
|
+24
dB
(12.3V)
Phone
Jack
(TRS)
OUTPUT
Connectors
Load
Impedance
Output
Impedance
Connectors **
* The input level required to obtain the nominal output level.
жж XLR-type connectors are balanced. 1=Ground, 2=+, З--
Phone jacks are balanced. Т-+, R=-, S=Ground
Ф Specifications subject to change without notice..