Rolls REQ215 User Manual
Page 2
INTRODUCTION
The ROLLS REQ series equalizers are intended for room equalizing or sound
shaping and the approximate frequency response curve can be seen graphically
by the settings of the frequency controls. Recording and broadcasting studios,
sound contractors and musicians will appreciate the low noise, straightforward
design, and versatile signal control of the REQ series.
INSTALLATION
Your REQ series equalizer may be installed in a standard 19î rack or placed in
any dry, well ventilated area. The 1/4î connectors are balanced with the tip being
positive (+) and the ring negative (-), or will assume an unbalanced state with
unbalanced (TS) connectors. The XLR connectors are pin 2 positive (+). The
chassis is lifted from the circuit ground (as are all ROLLS products) to help
prevent ground loops. Since there are three types of input/output connectors, one
type may be used on the input and another on the output. This helps to eliminate
the need for special cables.
FRONT PANEL
The POWER switch is on when the red portion is showing. The VOL control
provides the boost or cut settings for the input signal level. The LED bargraph
shows the actual output level in dB so the use will know when the headroom is
exhausted. EQ IN/OUT is for bypassing the equalizer circuits. The HPF and LPF
controls are shelving filters , their 3dB down frequencies are indicated on the
dials. For widest bandwidth, the HPF should be on 10Hz and the LPF should be
set to 30 kHz. Frequency band slider controls cut or boost the indicated frequency
by +/- 12 dB for the REQ131, or +/- 6 dB for the REQ215. When the slider is in
the center or detented position, the frequency is left unmodified.
REAR PANEL
The rear panel contains the XLR, 1/4î, and RCA input and output jacks. Connect
the power cable to a properly grounded AC outlet.
OPERATION AND APPLICATIONS
The REQ equalizers are useful signal processing tools where precise frequency
control is needed across the audio spectrum. The frequency band centers are
ISO standard, so it is compatible with most real time analyzers. When used with
an analyzer, the REQ units may be used to tune an acoustical environment to
avoid ringing (feedback), increase clarity, and flatten the overall frequency re-
sponse. An analyzer is useful in determining the amount of equalization needed.
Insert the graphic equalizer between the signal source and the power amplifier or
crossover. Adjust the level and equalization as required to yield the desired
system response. The HPF and LPF are used to band-limit the frequency re-
sponse to increase clarity and reduce noise.
SPECIFICATIONS
Frequency Response:
16 Hz to 30 kHz +/-3 dB
THD:
<.03%
S/N Ratio:
>90 dB
Max Input:
+21 dB (REQ131)
+17 dB (REQ215)
Max Output:
+21 dB (REQ131)
+17 dB (REQ215)
Input Impedance:
10K
Ω (20K balanced)
Output Impedance:
50
Ω
LED Levels:
+17, +10, 0, -7, and -13 dB
Frequency Centers:
31 ISO standard 1/3 octave +/-3% (REQ131)
15 ISO standard 2/3 octave +/-5% (REQ215)
Shelving Slope:
12 dB / Octave (REQ131)
6 dB / Octave (REQ215)
Size:
19" x 6" x 1.75"
(48.3 x 15.2 x 4.5 cm)
Weight:
5 lbs. (2 kg)
AUX 2
RETURN
0 10
AUX 1
RETURN/
TAPE IN LEVEL
0 10
HEADPHONE LEVEL
0 10
LEFT
RIGHT
0
+20
+6
+14
-10
-15
-20
-30
-
¥
+17
+8
0
-4
-13
HEADPHONE
OUTPUT
AUX 1
0 10
AUX 2
0 10
60
LOW
-15 +15
2.5 K
MID
-15 +15
12.5 k
HIGH
-15 +15
L R
BAL
11/12
0
+20
+6
+14
-10
-15
-20
-30
AUX 1
0 10
AUX 2
0 10
60
LOW
-15 +15
2.5 K
MID
-15 +15
12.5 k
HIGH
-15 +15
L R
BAL
9/10
0
+20
+6
+14
-10
-15
-20
-30
AUX 1
0 10
AUX 2
0 10
60
LOW
-15 +15
2.5 K
MID
-15 +15
12.5 k
HIGH
-15 +15
L R
BAL
7/8
0
+20
+6
+14
-10
-15
-20
-30
AUX 1
0 10
AUX 1
0 10
AUX 2
0 10
60
LOW
-15 +15
2.5 K
MID
-15 +15
12.5 k
HIGH
-15 +15
L R
BAL
5/6
0
+20
+6
+14
-10
-15
-20
-30
AUX 1
0 10
AUX 2
0 10
60
LOW
-15 +15
2.5 K
MID
-15 +15
12.5 k
HIGH
-15 +15
L R
PAN
4
0
+20
+6
+14
-10
-15
-20
-30
AUX 2
0 10
60
LOW
-15 +15
2.5 K
MID
-15 +15
12.5 k
HIGH
-15 +15
L R
PAN
3
0
+20
+6
+14
-10
-15
-20
-30
AUX 1
0 10
AUX 2
0 10
60
LOW
-15 +15
2.5 K
MID
-15 +15
12.5 k
HIGH
-15 +15
L R
PAN
1
0
+20
+6
+14
-10
-15
-20
-30
AUX 1
0 10
AUX 2
0 10
60
LOW
-15 +15
2.5 K
MID
-15 +15
12.5 k
HIGH
-15 +15
L R
PAN
2
0
+20
+6
+14
-10
-15
-20
-30
-
¥
-
¥
-
¥
-
¥
-
¥
-
¥
-
¥
-
¥
TAP
E
OUT
TAP
E
IN
R
L
TRIM
LIN
E
INSE
RT
MIC
1
INSE
RT
INSE
RT
INSE
RT
LIN
E
LIN
E
LIN
E
TRIM
TRIM
TRIM
TRIM
TRIM
TRIM
TRIM
PHANT
OM
P
OWER
LEFT
RIGHT
LEF
T
RIGHT
LEF
T
RIGHT
LEF
T
RIGHT
RIG
HT O
U T
AU X
2
RET.
LEFT
LEFT OUT
AUX 2
RET.
RIG
HT
AUX 1
RET.
RIG
HT
AUX 1
RE
T. L
EFT
AUX 1
OUT
AUX 2
OUT
MIC
2
MIC
3
MIC
4
MIC
5/6
MIC
7/8
MIC 9/
10
MIC 11/
12
+48V
OFF
+10
+60
+10
+60
+10
+60
+10
+60
+10
+60
+10
+60
+10
+60
+10
+60
VOLUME 1
VOLUME 2
P
OWER
A
MPLIFIER RA200
EQ
BYPASS
+17
+10
0
-7
-13
0
+12
LEVEL
16
20
30
50
100
HPF
LPF
500
400
1
200
HZ
KHZ
PWR
1.5
4
2
6
10
30 -12
20
25
31.5
40
50
63
80
100
125
160
200
250
315
400 500
630
800
1K
1.2K
1.6K
2K
2.5K
3.1K
4K
5K
6.3K
8K
10K 12.5K 16K
20K
+12
-12
LEFT RIGHT
EXAMPLE