Protech Audio 882 User Manual
Protech
MODELS COVERED
The Model 882 Line Amplifier/Tone Control card is
designed for frequency response shaping in professional
audio systems.
Typical applications are public address systems, broadcast
studios, sound reinforcement systems, headphone listening
systems, room combining systems, and recording systems.
The actual application of the line amp/tone control card is
found in such buildings as airports, factories, courthouses,
casinos, convention centers, hotels, racetracks, training sys-
tems, corporate boardrooms, etc.,.
The input section of the Model 882 is balanced, transformer
isolated, using a high quality bridging type line transformer.
The transformer is followed by an op-amp input buffer stage.
The gain of the input stage is fixed, at unity, in order to prevent
overdriving of the frequency shaping section.
The frequency shaping section provides a low frequency
adjustment capable of 12dB of cut and boost, and a high
frequency adjustment, also capable of 12dB of cut and boost.
Both sections are adjusted via separate trimpots, accessible
from the front of the plug-in card. The characteristics of the
frequency shaping circuit are classified as shelving type, and
centered at 1KHz.
The frequency shaping section is followed by a buffer amplifier,
to prevent changes in frequency response settings from
occuring, when the output load changes.
The output section consists of a low noise op-amp, with
adjustable gain, followed by a high quality output transformer.
The gain of the output section is adjustable via a trimpot
mounted on the backplane assembly. Adjustment of the gain
will have no effect on the low frequency or high frequency
settings.
The Model 882 may be mixed or matched or matched with other
INTEGRA III SYSTEM components, within the same card
frame, without degradation in performance. The Model 858B
Card Frame Package is a self powered card farme with 9 slots
available for audio cards. The Model 857B Card Frame Package
is a 10 slot card frame assembly intended for use with an external
power supply. Both card frame packages require just 3.5 inches
of vertical rack space.
The Model 882 Line Amplifier/Tone Control Card may be
expected to provide the user with years of dependable, uninter-
rupted quality service. For additional information, ordesign
assistance, contact:
APPLICATIONS ASSISTANCE
PROTECH
®
INSTALLATION & OPERATION
MANUAL
LINE AMP/TONE CONTROL CARD
8 8 2
1/06
INTEGRA III SYSTEM
Model 882 Shown
www.
protechaudio
.com
MODEL 882
LINE AMPLIFIER/TONE CONTROL
FREQUENCY ADJUSTMENT
CHART
FREQUENCY LOW FREQUENCY HIGH FREQUENCY
CUT BOOST
Full CCW Full CW
CUT (dB) BOOST (dB)
Full CCW Full CW
20 Hz
30 Hz
40 Hz
50 Hz
60 Hz
80 Hz
100 Hz
150 Hz
200 Hz
300 Hz
400 Hz
500 Hz
600 Hz
700 Hz
800 Hz
900 Hz
1 KHz
2 KHz
4 KHz
6 KHz
8 KHz
10 Khz
12 KHz
14 KHz
16 KHz
18 KHz
20 KHz
-16.25
-15.75
-15.00
-14.50
-14.00
-12.75
-11.50
-9.50
-7.50
-4.75
-3.00
-1.90
-1.25
-0.75
-0.50
-0.25
0.00
+16.25
+15.25
+14.75
+14.25
+13.50
+12.50
+11.75
+9.50
+7.50
+4.75
+3.00
+2.00
+1.50
+0.90
+0.40
+0.25
0.00
+1.50
+2.00
+4.50
+8.25
+10.00
+10.75
+11.25
+11.50
+11.50
+11.50
+11.50
+11.50
-0.75
-2.00
-5.00
-9.00
-10.50
-11.75
-12.00
-12.50
-13.00
-13.25
-13.75
-14.00
NOTE: Gain at Unity.
Gain settings made with pots at flat position, and 1KHz as reference frequency.
Protech Audio Corporation, PO Box 597, 192 Cedar River Road, Indian Lake, New York, 12842, Voice 518-648-6410 Fax 518-648-6395