Pro Co MS42A User Manual

PRO CO MULTIFACE™ SERIES MODEL MS-42

MS-42

FEATURES

4-CHANNEL MICROPHONE
SPLITTER

• Provides 2-Way Split for Low-Z Micro­phones

• 4 Splitter Channels in Single Rack Space

• Allows Assembly of Economical Expand­able Splitting System

MIC IN

1

NEUTRIK

DIRECT ISO OUT

NEUTRIKNEUTRI

K

MIC IN DIRECT ISO OUT

2

GND

NEUTRIK

LIFT

NEUTRIKNEUTRI

3

GND

K

LIFT

FRONT OF UNIT

The Pro Co Multiface MS-42
Quad Mic Splitter splits the signals
from each of four low-impedance
microphones (or similar sources) into
two outputs, enabling two
microphone preamplifiers to be fed
from one source. The primary
applications for the MS-42 are stage
monitor systems for musicians, where
an on-stage mixer is used, and in
remote or live recording applications,
where the P.A. system microphones
must also be fed to a recording mixer.
Transformer isolation in such
situations minimizes interference
from SCR lighting dimmers, radio
transmitters and 60 Hz AC power
wiring. The transformer-isolated
feeds retain the advantage of
common-mode noise rejection
inherent in the use of balanced lines.

The MS-42 is fitted with standard
3-pin XLR-type connectors for MIC
IN, DIRECT, and ISO OUT, so
hookup requires only standard
microphone cables. The use of the Pro
Co MBT-1 transformer allows the
MS-42 to provide floating,
low-impedance outputs with wide,
flat frequency response, ultra-low
distortion, and no ringing or
overshoot to degrade transient
response.

MIC IN DIRECT ISO OUT

NEUTRIKNEUTRI

NEUTRIK

K

shields and GND/LIFT switches provide
isolation and buzz-free operation in
virtually any environment.

and aluminum "Uni–box™" construction
enclosure is finished in a durable black
texture powder coat finish with black
anodized aluminum side channels. Easy–
to–read control graphics are incorporated
into the Lexan® front and back panel
overlays. Inside, the specially designed
transformers combine superb audio
quality with unsurpassed noise rejection.

standard 19" (482.6mm) rack. Top­quality connectors and switches provide
trouble-free service even in abusive
situations such as remote broadcast and
recording operations. The rack-mounting
design allows the user to assemble a
conveniently packaged expandable
splitting system that combines top­quality audio performance and isolation
with an economical price.

MIC IN DIRECT ISO OUT

4

GND

LIFT

NEUTRIKNEUTRI

NEUTRIK

GND

LIFT

MS-42

K

The transformer’s dual electrostatic

The MS-42's rugged 16–gauge steel

The MS-42 can be mounted in any

• Great for Musicians’ Monitoring and
Remote Recording

• Connects with Standard Mic Cables

• High-Quality Transformer-Isolated
Outputs

• Rugged "Uni–box™" Construction for

Super Strength and Shielding

• All Connectors Accessible from Front

CONTROLS DESCRIPTION

MIC IN:

Female 3-pin XLR-type connector accepts
signal from low-impedance (150 ohm
nominal) microphone or similar source.
Input impedance (with 1.0 kohm loads
on LOOP and ISO OUTS): approx. 500
ohm.

DIRECT:

Male 3-pin XLR-type connector wired in
parallel with MIC IN provides signal to
feed mixer input.

ISO OUT:

Male 3-pin XLR-type connector provides
floating transformer-isolated
low-impedance output to feed mixer
input. Recommended load impedance:

1.0 kohm.

GND/LIFT:

GND position connects pin 1 of MIC IN/
LOOP OUT to pin 1 of ISO OUT. LIFT
position “floats” ISO OUT. Used to
reduce hum and buzz by eliminating
ground loops and providing proper
grounding for various conditions.

MS-42/042198

PRO CO SOUND, INC./135 E. KALAMAZOO AVE./KALAMAZOO, MI 49007 USA/www.procosound.com PRO CO

PRO CO MODEL MS-42 MICROPHONE SPLITTER

TYPICAL PERFORMANCE

All measurements made with 150 ohm source feeding MIC IN and

1.0 kohm load on ISO OUT to simulate typical “real world” microphone
and mic preamp. 0 dBv ref. = .775 volt.

FREQUENCY RESPONSE:
20 Hz-20 kHz, +/- .5 dB @ -15 dBv output.

-3 dB @ approximately 65 kHz.
TOTAL HARMONIC DISTORTION:

Less than .03% 20 Hz-20 kHz @ -30 dBv output.
Less than .1% 30 Hz-20 kHz @ -15 dBv output.
Less than .25% 20 Hz-20 kHz @ -15 dBv output.

PHASE RESPONSE:
Less than -20 degrees @ 20 kHz (ref. 1.0 kHz).

RISE TIME:
Less than 4.5 microseconds (2.0 kHz square wave, 10%-90%).

INPUT IMPEDANCE:
Greater than 1050 ohm @ 1.0 kHz.
Greater than 1080 ohm @ 10 kHz.

Nominal source impedance is 150 ohm.

OUTPUT IMPEDANCE:
Less than 270 ohm @ 1.0 kHz.
Less than 300 ohm @ 10 kHz.

Nominal output impedance is 1.0 kohm.

VOLTAGE LOSS:
Less than 1.0 dB @ 1.0 kHz.

MAXIMUM INPUT LEVEL FOR 1% THD:
0 dBv @ 20 Hz.
+4 dBv @ 30 Hz.
+8 dBv @ 50 Hz.

NOTE: Phantom power (if required) must be supplied by mixer (or
suitable power supply) connected to LOOP output.

ENGINEERING SPECIFICATIONS

The microphone signal splitting unit shall be suitable for interfacing
each of four (4) balanced or floating low-impedance (150 ohm nominal)
microphones or similar signal sources to two (2) balanced or floating
low-impedance (1.0 kohm nominal) microphone preamplifier inputs.
There shall be four (4) channels with features as follows:

There shall be a 3-pin female XLR-type connector for input from
the source. There shall be a parallel or direct output from a 3-pin male
XLR-type connector. There shall be a transformer-isolated
low-impedance output from a 3-pin male XLR-type connector. The
transformer shall be a Pro Co MBT-1 Microphone Bridging
Transformer. The primary electrostatic shield shall be connected to pin
1 of the source input and direct output connectors. The secondary
electrostatic shield shall be connected to pin 1 of the transformer­isolated XLR output. There shall be a ground-lift switch to allow the
shields to be connected together or isolated as required.

The enclosure shall be constructed in the Pro Co "Uni–box™"
design with 16–gauge steel black zinc finish top and bottom plates, 1/8"
black anodized aluminum front plates, back plates and side channels.
Control functions shall be identified by a printed Lexan® front and back
panel overlay. Switches shall be of the miniature “rocker” type and shall
be recessed. The enclosure shall be provided with 2 miniature handles
mounted on the front plate. The enclosure shall be suitable for standard
19" EIA rack mounting. The dimensions of the unit shall be approxi­mately 4-3/4" D by 19" W by 1-3/4" H. (120.7mm D by 482.6mm W by

44.5mm H).

The microphone signal splitting unit shall be a Pro Co Multiface
MS-42 Mic Splitter.

THE PRO CO MBT-1 TRANSFORMER

The MBT-1 is a carefully designed, custom-built 1:1 microphone
bridging transformer whose characteristics are optimized for use with
balanced low-impedance microphones or similar sources.

Special winding techniques and a high-permeability (80% nickel)
core lamination preserve full frequency response while minimizing
signal losses and other “loading” effects. Separate electrostatic shields
for primary (input) and secondary (output) windings reduce capacitive
coupling of ground-borne electrical noise between main and stage
monitor or recording mixers, eliminating annoying 60-Hz hum and buzz.
The source impedance of the MBT-1 is very similar to that of a low­impedance microphone to ensure proper matching to the input circuitry
of the mixer. The result is clean transient response (no overshoot or
ringing) and low distortion even at low frequencies and high input
levels.

PRO CO MODEL MS-42

1

MIC

2

IN

3

1

DIRECT

2

3

DIMENSIONS

WEIGHT.......4.20 lbs.

1.91 kg.

ONE OF FOUR CHANNELS

PRO CO SOUND, INC./135 E. KALAMAZOO AVE./KALAMAZOO, MI 49007 USA/www.procosound.com PRO CO

BROWN

RED

GREY

MBT-1
TFMR

BLACK

ORANGE

YELLOW

GND
LIFT

ISO

OUT

1

2

3

TOP VIEW

FRONT VIEW

SIDE VIEW

SHIPPING

WEIGHT.......5.0 lbs.

2.25 kg.

19" / 482.6mm

4.75" / 120.7mm

1.75" / 44.5mm