MODELS COVERED
INTEGRA III SYSTEM
The 800 Series Mixer/Preamplifiers and Mixer/Line Ampli-
fiers are designed for use in professional audio applica-
tions. Each model is designed to accept multiple microphone
signals in, and combine the individual signals into one
common output signal.
Typical applications are public address announcements,
with different paging stations, program material that must
be combined from different studios, headphone listening
systems where the user can directly interface with various
program sources, or audio recording systems, where
different program material must be fed to the recorders at the
same time.
The actual application of the mixers is found in buildings
such as airports, courthouses, factories, casinos, conven-
tion centers, libraries, racetracks, training systems, and cor-
porate boardrooms, to mention just a few.
The 800 Series mixer cards are designed to incorporate a
combination of features that will allow the units to deliver
maximum reliability. Each circuit is designed with a mini-
mum of components, to reduce the possibility of failure,
while still maintaining performance and feature criteria.
Each of the 800 Series mixer cards, is designed with the same
combination of features. The input level type, the link feature
(not available on 5 input units), and number of inputs are the
only variables between models.
The gain structure of the 800 Series mixer cards allows the
output level to be adjusted from off to +55dB, with respect to
the input level. The trimpots used to adjust the input gains, are
mounted on the backplane assembly. The alignment procedure
is described on page two of this manual.
The input sections, and the output section of each model are
individually isolated using the highest quality audio
transformers. In addition, each input, and the output section
on every model has individually adjustable operational
amplifiers. These features provide the maximum in isolation.
Each model may be mixed or matched with other INTEGRA III
SYSTEM audio cards, to create a complete audio system.
These products are designed to provide the user with high
quality audio, for years of uninterrupted service.
PROTECH
®
INSTALLATION & OPERATION
MANUAL
AUDIO MIXER CARDS
870B*
871B*
872B*
873B*
1/03
Model 877B Shown
874B
875B
876B
877B
*Microphone Level
Input
www.
protechaudio
.com
Protech Audio Corporation, PO Box 597, 192 Cedar River Road, Indian Lake, New York, 12842, Voice 518-648-6410 Fax 518-648-6395
