Orban 674A - Orban 674 A Specifications; Electrical Specifications; Circuit Design Overview; Operating Temperature

Specifications:
All
specifications
apply
when
driving
600
ohms
or
higher
impedances.
Noise
measured
on
an
average-reading
meter
through a
20-20,000Hz
bandpass
filter
with
!8dB/octave
Butterworth
skirts.
ELECTRICAL
Input:
Impedance,
Load
(each leg):
I00K
in
parallel
with
lOOOpF,
electronically
balanced
Impedance,
Driving:
Ideally 600
ohms
or less,
balanced
or
unbalanced
Nominal
Input
Level:
Between
-
10
and +
4dBm
Absolute
Overload
Point:
+
26dBm
Output:
Impedance,
Source:
47
ohms
in
parallel
with lOOOpF,
unbalanced
(Optional
transformer
balanced
600
ohm outputs)
Impedance,
Load:
Should be
600
ohms
or
greater
—will
not
ring
into any
capacitive
load
Nominal
Output
Level:
+
4dBm
Max.
Output
Level
Before
Clipping:
greater
than
+ 1
9dBm,
20-20.000H
z
Frequency
Response:
±
0.25dB;
20-20,000Hz: EQ
controls
set
at
zero
detents
Available
Gain:
+
!2dB;
adjustable
to
-infinity by
means
of
front-panel
GAIN
control
Slew
Rate:
Varies
between 6
and
1 3V/us
depend-
ing
upon
setting
of
GAIN
controls;
slew-
ing is
symmetrical.
Internal
bandlimiting
assures
that
slew
rate
limiting
will
not
occur even
with the
most
severe
equalization
and
program
material.
Square
Wave
Response:
Square
wave
exhibits
no
spurious
ring-
ing at
any
output
level.
The
only
ringing
observable
is
that
theoretically
associated
with
any
given
equalization
curve.
Total
Harmonic
Distortion:
Less
than
0.08%,
20-20,000Hz
(
+
!8dBm)
SMPTE
Intermodulatlon
Distortion:
Less
than 0.05%
(
+
!8dBm:
60/700Hz,
4:1)
Noise at
Output:
Less
than
-
78d8m
(EQ
in,
filters out,
controls
centered)
Overload/Nolse
Ratio:
Better
than 1 1
3dB
for any
single
band-
pass
filter,
for
any
settings
of
TUNING or
BANDWIDTH
controls.
Equalization
Ranges:
±
!6dB
peaking EQ,
Reciprocal
Tuning
Ranges:
20-60Hz;
40-150Hz; 1
!0-310Hz;
230-750Hz;
480-l900Hz;
l.l-4.5Hz;
2.8-9.0kHz;
5.9-21 kHz.
Dials
calibrated
at ISO
preferred
frequencies.
Crosstalk:
Typically
better
than
-
55dB@
20kHz;
improves at
6dB/octave
below
that
fre-
quency.
"Q"
Range:
Greater
than 0.5
to 10
for any
setting
of
the
TUNING
control.
Low
Pass
Filter
Section:
Tunable
in
2
ranges:
200-2000Hz
or
2.0-20kHz, 1
2dB/octave,
(2nd-order
But-
terworth)
High Pass
Filter
Section:
Tunable
in 2
ranges:
20-200Hz or
200-2000HZ, 1
2dB/octave,
(2nd-order
Butterworth)
Overload
Indicator:
Lamp
lights
for
200ms if the
instan-
taneous
peak
output
of
any
amplifier
rises to
within I dB
of
its
clipping
point.
Circuit
Design:
Active
RC
realized
with
FET-input
opamps.
Line
driver
employs
discrete
transistor
current
booster.
Operating
Temperature:
0-50°
C
Power
Requirements:
1
15/230VAC
± 10%;
50/60Hz; 12
watts
PHYSICAL
Operating
Controls
(each
channel):
EQUALIZATION,
TUNING,
and
BAND-
WIDTH
for
each
of eight
bands.
TUN-
ING,
RANGE
( x
I;
X 10),
and
FILTER
IN/OUT
for
each
filter.
EQUALIZATION
IN/OUT,
POWER
ON/OFF,
and
GAIN
for
entire
equalizer.
Panel:
19"
X S'A"
(48.3
X
13.3cm):
3
units
Chassis
Depth
Behind
Panel:
5
'A"
(13.3cm)
Weight:
Net:
I libs.
(5
kg);
Shipping:
13
'A
lbs.
(6.1
kg)
AC
Cord:
3-wire
U-ground
to
USA
Standard
Connectors:
140 type
barrier
strip
(5#
screw);
holes
punched
for
XLR-type
connectors
(Switchcraft
D3F
and
D3M
or equal)
Circuit
Ground:
Available
on
barrier
strip;
normally
jumpered
to
chassis.
Options:
1)
Plexiglass
security
cover
for EQ
and
filter
sections
2)
Balanced
transformers
in two
or
four
outputs
3)
XLR-type
connectors
on
input
and
two
or
four
outputs
4)
Phone
jacks
on input
and
two
or
four
outputs