M4

mkII

Portable Audio Mixer

Operation Manual for Mixers with PCB V1.5
Copyright 2002
Professional Sound Corporation
Printed in the U.S.A.

TABLE OF CONTENTSDESCRIPTION…………………………………………………………………………………...4
SAFETY WARNINGS…………………………………………………………………………...4
APPLICATIONS…………………………………………………………………………………4
FUNCTIONSINPUTS………………………………………………………………………………...5-7
A.

BALANCED INPUTSB.

INPUT LEVELSC.

MICROPHONE POWERINGD.

LOW CUT FILTERE.

CHANNEL GAINF.

CHANNEL PANSH.

BOOM POLE REMOTE CONTROLOUTPUTS……………………………………………………………………………..7-9
A.

BALANCED OUTPUTS

B.

MULTIPIN (BETA) CONNECTORC.

OUTPUT LIMITERSD.

TRANSCRIPTION OUTPUTSE.

HEADPHONE MONITOR OUTPUTF.

TAPE RETURN GAINMETERS…………………………………………………………………………………9A.

PEAK READING METERS

B.

NIGHT (BACKLIGHT) USE

2

ADDITIONAL FEATURES………………………………………………………..10-11
A.

SLATE MICROPHONEB.

REFERENCE OSCILATORC.

BATTERY TESTD.

M-S AND X-Y STEREO RECORDINGE.

WIRELESS MICROPHONE POWER DITRIBUTION

POWERING………………………………………………………………………...12-13
A.

INTERNAL POWER, NP-1 BATTERYB.

INTERNAL POWER, ALKYLINE BATTERIESC.

EXTERNAL POWERCONSTRUCTION………………………………………………………………….13-14
A.

CHASSISB.

ELECTRONIC TOPOLOGYC.

ENVIRONMENTAL OPERATIOND.

PORTA BRACE CASE

INTERFACING……………………………………………………………………..14-15
A.

TO BETACAMSB.

TO RDAT RECORDERSC.

TO WIRELESS MICROPHONESWARRANTY AND NON-WARRANTY SERVICE…………………………………15
SPECIFICATIONS…………………………………………………………………….16

3

DESCRIPTION
Thank you for purchasing the Professional Sound Corporation M4mkII Portable
Audio Mixer. PSC is confident that this new M4mkII Mixer has set new standards
for portable mixer technologies and features. Please feel free to contact us if you
have any comments or questions concerning your new mixer. Additionally, we
invite you to share your suggestions for new products you would like to see
developed.
Professional Sound Corporation extends a one-year warranty on parts and labor
to all M4mkII Mixer owners who return their warranty cards at the time ofpurchase. This warranty gives you specific rights, which are stated on the card,and enables us to keep you informed of product updates.
The PSC M4mkII Mixer provides all the functions necessary to produce studioquality recordings in the field. It’s user friendly features, rugged design and sonicpurity make the M4mkII Mixer perfect for electronic news gathering (ENG)
electronic field production (EFP) and feature film production.
HEARING SAFETY WARNINGS:
Please be sure that you have read this entire manual before operating thismixer.
While special attention has been given to your safety and hearing
protection, the operator determines proper and safe operating levels.
Please note the following:
Always turn down the headphone volume before plugging in yourheadphones.
Always operate your headphones at the lowest practical level.
Be especially cautious in unknown or widely varying environments.
Remember, your ears are your livelihood. Turn it down!

APPLICATIONS
•
•
•
•
•

Electronic News Gathering
Location recording (Dialogue and Music)
Digital Recording and Playback
Broadcast remotes
Desktop Mixing for Video Post Production

4

INPUTS:A.

BALANCED INPUTSThe PSC M4mkII Audio Mixer provides four input channels utilizing female XLR
connectors. The studio grade input circuitry is transformer balanced for improved
RF rejection and in-field practicality. The XLR connectors are wired as follows:
Pin 1 shield (ground), Pin 2 Audio high (in phase), Pin 3 Audio low (out of phase).
Balanced wiring enables longer cable runs without the worry of excessive noisedue to nearby electromagnetic and radio frequency interference. Thesebalanced inputs may be unbalanced if desired. Either pin 2 or 3 may be tied to
ground (pin 1) to unbalance the inputs of the M4mkII Mixer. Note: The AES
standard for unbalancing an XLR connector is to tie pin 3 to ground (pin 1).
B.

INPUT LEVELSThe PSC M4mkII Mixer can accommodate a wide range in input levels.
Microphone levels of all types can be handled as well as line level signals. The
input range of the M4mkII Mixer is –60dBu to +4dBu. Thus the M4mkII is
compatible with all forms of consumer and professional audio equipment. The
input level switches are located below and to the right of each input XLR
connector. These input level switches provide for three level settings: “D”
Dynamic Microphone (0dB attenuation), “C” Condenser Microphone (15dB
attenuation), and “L” Line Level (50dB attenuation) These input level attenuation
settings are used to correctly interface sources of varying levels to the M4mkII’s
preamplifiers. Correct level matching ensures maximum headroom and lowest
possible noise floor.
C.

MICROPHONE POWERINGThe M4mkII Mixer can accommodate the most popular microphones used today.
The microphone powering switches are located directly below the input XLR
connectors. They can be switched to either Dynamic (D) or 48Phantom (48).
In the Dynamic position the mixer provides no microphone powering. This
position is used with Dynamic Microphones, Line Level inputs and when using
Wireless Receivers.
In the 48 Phantom Position the mixer provides 48 volts DC to power 48PH
microphones or simplex powered microphones with a range of 9 to 52 volts or 12
to 52 volts. Pin 1 is shield to ground while pins 2 and 3 carry 48 volts DC. The
term “phantom” is derived from the fact that there is no voltage potential
developed across a dynamic microphone transducer that would interfere with its
operation. However, most portable wireless receivers will not operate with 48PH
turned on. We strongly recommend setting inputs to dynamic for use with all
wireless systems.
It should also be noted that the PSC M4mkII Mixer contains special electronics
that automatically shut off the 48PH DC to DC converter if none of the four5

microphone powering switches are set to 48 Phantom. This feature will conserve
approximately 12mA of supply current.
In the interest of keeping the M4mkII Mixer design simple and up to date withtoday’s technology, we have not offered “12T” or “AB” microphone powering.
Although some “12T” microphones are still in existence, all new microphone
designs are 48PH.
D.

LOW CUT FILTERS

Each input channel of the M4mkII Mixer is equipped with an active low cut (highpass) filter. These filters are activated via the three way switches located below
the adjacent channel fader knobs. These filters will attenuate all frequencies
below a preset frequency at a rate of 12dB per octave. When set at “20Hz”,
frequencies below 20 Hz are effectively rolled off with the mixer operating at full
frequency response. Optional low cut filter settings of 80Hz and 140Hz will roll
off the frequencies below these figures at a rate of 12dB per octave (-3dB level at
80Hz and 140Hz respectively. Low cut filtering is important in location recording
where wind noise can cause pre-amplifier overload. This effect can be
minimized by switching the low cut filter setting to either a 80Hz or 140Hz cutoff.
The low cut filter switches are located on the front of the M4mkII Mixer.
E.

CHANNEL GAIN

In order to limit noise and increase headroom, the channel fader controls arelocated in the feedback path of the pre-amplifiers. This provides continuously
variable gain rather than just a decrease in channel output level when an
overload situation occurs. This results in increased headroom and lower chanceof signal clipping (severe distortion).
F.

CHANNEL PANS

The new M4mkII Audio Mixer contains front panel mounted pan pots. These panpots are used to route the individual input channel’s signal to either the left or
right summing buss. These pots are equipped with center detents allowing thepots to remain centered when the operator so desires. These pots are also
equipped with a retracting mechanism that allows the pots to be pushed in flushwith the front panel after they have been set to the operators desired setting.
This helps keeps the front panel “clean” and uncluttered and reduces the chanceof the operator accidentally bumping the pan pot setting.
H.

BOOM POLE REMOTE CONTROLThe M4mkII Mixer offers the ability to remotely control the audio level of thechannel one input via a boom pole mounted remote control. When used, thisremote control works as a gain control for the channel one input. It allows theoperator to control the overall gain of the first preamp. To use this feature, you

6must set of the mixer as you normally would for the type of microphone being
used, I.E. 48PH power on, etc. Then you attach the boom pole remote control tothe boom pole with it’s captive Velcro TM straps. The cable should exit the
remote control toward the heel end of the boom pole. Then simply plug the
remote control cable into the mixer’s “remote” connector located near thechannel one input XLR. Set the remote controls slide fader to it’s mid position
and adjust the mixer’s channel one fader for normal recording levels. You are
now ready to remotely control the channel one input of your M4mkII Mixer.
Sliding the fader toward the heel end of the pole decreases signal level, sliding
the fader toward the microphone end of the pole increases signal level. This
remote control allows for approximately 40dB of control range. It should be
noted that using the boom pole remote control requires that the mixer channel
fader be set slightly higher than normal. Because of this please heed thefollowing safety warning:*SAFETY NOTE*ALWAYS TURN DOWN THE MIXER’S CHANNEL ONE
INPUT FADER BEFORE DISCONNECTING THE BOOM POLE REMOTE
CONTROL. INADVERTENT HIGHER THAN EXPECTED VOLUME LEVELS
MAY RESULT IF YOU DISCONTECT THE BOOM POLE REMOTE CONTROLWITH THE CHANNEL FADER OPEN!
OUTPUTS:A.

BALANCED OUTPUTSThe M4mkII Mixer contains very high quality custom-made audio output
transformers.
These transformers have been designed to provide wide
bandwidth, low distortion and real-world ease of use. Transformers have beenchosen over a transformerless design because of their inherent ability tointerface with virtually any other device, especially RF based products. This isvery important in this day and age in consideration of the frequent use of multiple
RF receivers and transmitters. These outputs are available via the right handpanel mounted male XLR connectors. These outputs are switchable between
line or microphone levels. At the line level setting, the mixer outputs deliver anominal 0dBv (1V) signal into 10K Ohm loads. When set to microphone level,
the outputs supply –50dBv signal levels. Please note that 10K Ohm loads are
typical of the loads imposed on the mixer by most Betacams, and other recording
devices. Additionally, the M4mkII Mixer’s outputs are capable of driving 600Ohm loads.
B.

MULTI-PIN (BETACAM) CONNECTOR

The M4mkII Mixer is equipped with a multi-pin in/out connector designed
primarily to interface with Betacams. This connector provides the left and rightbalanced outputs as normally found on the XLR output connectors as well as left
and right tape returns used for confidence monitoring. This multi-pin connection
provides a convenient means of interfacing to Betacams with only one
connection. In addition, this connection is located on the left hand side (inputsside) of the mixer. By locating the connector on this side of the mixer, all your7

cables can be conveniently routed from one side of the mixer providing a clean
and compact setup for use on the run.
C.

OUTPUT LIMITERS.

The limit threshold (activation level) is factory set at +3 on the meter. The limiters
compress the signal at approximately 2.7 to 1 ratio. This is to say an increase of
2.7dB in input signal will result in only a 1dB increase in output signal. Output
channel limiting is displayed on the LCD meter.
The M4mkII contains two separate limiters that are controlled by one front panel
mounted switch. This switch has three settings: Off, Separate (S), and Ganged(G). In the off position, no limiting occurs.
In the separate position, the limiters act independently of each other. This isespecially useful when recording split tracks. I.E. interviewer and interviewee on
separate channels. Thus, if one person un-expectantly raises their voice, that
limiter will activate, but the other will not. In the ganged mode, both limiters aretied together and can be triggered by either input. This is useful in recording
stereo, as independent limiting would alter the stereo image.
PRACTICAL USE NOTE: IT IS HIGHLY RECOMMENDED THAT THE
LIMITERS BE USED AT ALL TIMES WHEN RECORDING TO BETACAM
TYPE CAMERAS.
Most video cameras have limited audio track headroom and can easily beoverloaded resulting in distortion of the recorded audio. Play it safe, use thelimiters!
D.

TRANSCRIPTION OUTPUTSThe M4mkII Mixer also contains a dedicated microphone level output used tofeed transcription recorders. This connector is located directly below the main
XLR outputs. It is a 3.5mm Stereo connector wired as follows: Tip = Left, Ring is
Right, Sleeve = Ground. This connector provides a –45dBv signal. This iscompatible with most transcription cassette recorders.
E.

HEADPHONE OUTPUT

The Headphone output is located directly on the front panel of the mixer. Thislocation was chosen to allow the operator to easily plug/unplug the phones from
the M4mkII Mixer and other devices. The M4mkII Mixer’s headphone amplifier
circuitry is designed to drive virtually any headphone with an impedance rating of
32 to 600 Ohms. The headphone circuitry is controlled by the use of two
switches and a convient front panel mounted volume control. The two switches
are used to control what the operator listens to. The most commonly used switch
is located on the front panel and is used to allow the operator to chose between
monitoring normal stereo, left channel to both ears or right channel to both ears.
This feature is an improvement over previous M4 designs. The second switch is8located on the right hand side panel of the mixer. This switch is normally set tothe stereo position. Under special circumstances, you may wish to monitor yourheadphones in Mono or decode MS signals when recording in MS Stereo.
Please see MS Stereo section of this manual.
*SAFETY NOTE* ALWAYS TURN DOWN THE HEADPHONE VOLUMEBEFORE PLUGGING IN YOUR HEADPHONES.
F.

TAPE RETURN

The M4mkII Mixer is equipped with tape returns used to monitor tape confidence
heads from most any recording device. These tape monitor amplifiers can be
adjusted to match the signal levels of most any device. These levels areadjusted using a small jewelers screwdriver (or “Greenie” screwdriver). The
adjustment points are located directly above the Mutlipin connector. The
tape/direct switch is located on the upper right hand corner of the front panel.
When set to ”D” (Direct) the phone amplifiers to monitor the mixers output signal.
If switched to “T” (Tape), then the phone amplifies monitor the external sourcesuch as the Betacam.

METERS:A.

PEAK READING METERS

The M4mkII Mixer is equipped with a custom made LCD meter. We designed
this meter to be easy to read and camera emulating. Because the most common
use of this type of mixer is with Betacams, we designed the M4mkII’s meters toemulate the peak reading attributes found on many Betacams. In this manor,
you can be confident of your recording levels even when the Betacam is being
fed via Betasnake cable or wireless transmission. The LCD meter also displays
Left and Right Limiter functions as well as Low Battery Warning. When the “LoBat” indicator comes on, you have approximately 30 minutes of battery life
remaining. You should replace the batteries at your earliest convenience. This
low battery indicator automatically senses the use of a NP-1 rechargeable battery
or AA alkaline batteries and adjusts itself accordingly.
The M4mkII Mixer is equipped with meter lamps used for night viewing of themeters. The light source for this meter back lighting is provided by a 2200mc(2.2 candela) high performance “white” LED in conjunction with a specially madewoven fiber optic light transmission panel. These two new technologies werechosen as they provide good quality back lighting without adding noise to themixer as some Electro-luminescent systems do. The use of the meter backlighting adds approximately 30mA of power consumption to the mixer.

9ADDITIONAL FEATURES:A.

SLATE MICROPHONE

The M4mkII Mixer is equipped with a slate microphone. This microphone isactivated when the front panel “slate” momentary push button switch is pressed.
The slate microphone allows the operator to put voice slates (notes) on tape forlater reference. These are normally notes for editing tape. A level adjustment
trim pot is located on the bottom panel of the M4mkII Mixer. Turning theadjustment clockwise will increase the slate microphone level. Turning theadjustment counter-clockwise will lower the level.
B.

REFERENCE OSCILLATORThe M4mkII Mixer is equipped with a reference oscillator used for setting oflevels between the mixer and recorder. This known reference level is also used
when transferring tape during editing. The M4mkII’s oscillator operates at 440Hz
at “0” on the meters. When setting up typical Betacams with LCD bar graphmeters you simply adjust the Betacams inputs until “0” is reached. From thatpoint on, you can monitor levels from the mixer only. We have chosen 440Hz
simply because it is much more pleasant in your headphones than the typical
1Khz used by other manufactures. We have used 440 Hz on our mixers formany years. The reference oscillator is equipped with a level adjustment trim pot
located on the bottom panel of the M4mkII Mixer. This adjustment is factory
calibrated and should not be adjusted without proper measurement equipment.
C.

BATTERY TESTIn addition to the low battery indicator on the LCD meter, the M4mkII Mixer isequipped with a push button activated battery test function: When pressed theremaining battery life is displayed on the top (left meter). A full battery will
indicate “0” on the meter. A dead battery will not indicate on the meter. You canread the meter as a “fuel gauge”. Full bar = full battery, half bar = half battery,etc. This battery level meter automatically adjusts for the differences in battery
types, NP-1 or alkaline. This battery test function can be adjusted to specific NP1 type batteries via a bottom panel mounted trim pot. The mixer is factory
shipped with the adjustment set for 12.6V NP-1 batteries. A fully charged 12.6V
NP-1 battery will register “0” on the meter. If you use 13.8V NP-1 batteries, you
can re-adjust the meter to “zero” on a fully charged battery. Because the M4mkII
Mixer uses only a small amount of current, the mixer will operate for many hours
on even a “dead” NP-1 battery. Because the mixer will operate down to 6.5Vdc,
it will continue to operate long after the low battery indication comes on whenusing NP-1 batteries. This can be useful in the field as even a battery considered“dead” by the camera operator might work with your M4mkII. Note that overdischarging of re-chargeable batteries on a regular basis is not a recommended
practice for everyday use!

10

D.

M-S AND X-Y STEREO RECORDING

The PSC m4mkII Mixer can be used to make stereo recordings in both the midside and X-Y stereo techniques. The M4mkII Mixer is equipped with an input
channel ganging switch designed to allow the ganging of input channels 3 and 4.
This switch is located on the bottom panel of the mixer. When switched to the“ganged” position, both input channels 3 and 4 are controlled by pot 4. All
microphone powering and attenuation settings remain independent. X-Y stereo
recordings are accomplished by plugging in two identical microphones intochannels 3 and 4. The channel 3 pan pot is set to the extreme left and thechannel 4 pan pot is set to the extreme right. The headphone monitor modeswitch is set to “stereo”.
If M-S stereo recordings are desired, the “M” or middle microphone (cardiod
pattern) is plugged into channel 3. The “S” or side microphone (Figure 8 pattern)is plugged into channel 4. As with the X-Y setup, pan pot 3 is panned to theextreme left and pan pot 4 to the extreme right. In this case, the headphonemode switch is set to “MS”. In the MS mode, the headphone amplifiers are fed
MS decoded signals. The left headphone amp is fed M-S signals and the rightheadphone is fed M+S signals. In this manner, MS signals appear as standard
stereo signals for headphone monitoring purposes. Note that the MS decode
function only affects the headphone feeds, not the main XLR outputs.
More complete descriptions of the M-S and X-Y stereo recording techniques canbe found in the literature of the major microphone manufacturers such as
Neuman, Sennheiser, and Scheops.
E.

WIRELESS MICROPHONE POWER DISTRIBUTIONYour new M4mkII Mixer is equipped with two four pin Hirose tm connectors
designed to output DC power to operate you wireless microphone receivers. The
two connectors are located directly below the channel four input XLR connector.
These two connectors are wired as follows:
PIN 1 = GROUNDPIN 4 + POSITIVE BATTERY VOLTAGE.
This is the wiring standard found on most Betacams. Many wireless microphonemakers such as Lectrosonics tm supply cables pre-made for this purpose. If you
make you own cables, please understand that you must match grounding
potentials or risk equipment damage! Please also note that while the new
M4mkII Mixer has extensive RF filtering built input the power line supplying theseconnectors, there remains a possibility that not all wireless frequencies will
operate without interference with either the mixer or other wireless units. Also
note that all current supplied by these connectors is routed through the M4mkII
Mixers Polyfuse (automatic resetting fuse) and thus there are limits to how muchcurrent can be supplied by these connectors. That limit is typically 1 Amp.
Excessive current will cause the Polyfuse to trip and shut off the mixer. To
restore power, simply switch off the mixer, disconnect the offensive load and turnthe mixers power back on.

11

POWERING:
A. INTERNAL POWER, NP-1 BATTERY
The PSC M4mkII Mixer is the first compact ENG mixer to offer the ability to be
powered from an internal NP-1 rechargeable battery. This feature provides aconvenient way of powering the mixer without added size, adapters or cables. In
addition, because the NP-1 battery is securely housed within the mixer, there islittle chance that the battery could be knocked loose as with conventional battery
adapters.
There are several high capacity NP-1 batteries now on the market. These
include the standard Ni-Cad, Nickel Metal Hydride and most recently Lithium-Ion.
Most of these batteries are available in both 12.6 Volt and 13.8-Volt varieties.
Either voltage will work in your M4mkII.
The M4mkII Mixer consumes
approximately 175mA of current when no microphones are being powered. Thistranslates into a battery life of 10 to 20 hours depending on the battery type.
Powering wireless will shorten battery life considerably depending upon wirelessmodels selected. The NP-1 battery pack is held in place with a simple spring
steel latch. To remove the battery simply push down on the latch and pull out thebattery.
B. INTERNAL POWER, ALKALINE BATTERIES
Eight “AA” alkaline batteries can also power the M4mkII Mixer. These batteries
are housed in a convenient battery tray designed to be inserted in the standard
NP-1 battery slot. When using alkaline batteries, you can expect 8 to 12 hours ofoperation under normal circumstances. The PSC M4mkII Mixer automaticallysenses the use of NP-1 battery or Alkaline cells. It automatically adjusts the “lowbattery” warning point to match the battery used.
PRACTICAL USE NOTE:NEVER STORE YOUR M4mkII MIXER FOR
EXTENDED PERIODS OF TIME WITH THE ALKALINE BATTRIESINSTALLED IN THE MIXER. THERE IS A POSIBILITY THAT THE BATTRIES
MAY LEAK CAUSING CORROSIN OF THE MIXER. BATTREY LEAKAGE
AND THE RESULTING COOROSIN DAMAGE IS NOT COVERED UNDER THE
M4mkII MIXER WARRANTY.
C. EXTERNAL POWER
The PSC M4mkII Mixer can also be externally powered from any source of DC
power from 7 to 18 Vdc. The mixer consumes approximately 175 mA over thisvoltage range. This current consumption is nearly constant and does not vary
dramatically over operating voltages like other mixers. The external power
connector is located on the right side of the mixer below the NP-1 battery slot.
Pin outs of this Hirose 4 pin connector are as follows:
Pin 4 (+) Positive
Pin 1 (-) Negative
12

This external DC input is protected from reverse polarity. If you mis-apply
connect external power of the incorrect polarity, the mixer will not be damaged, it
simply will not power up.

CONSTRUCTIONA.

CHASSISThe new M4mkII Mixer chassis has been designed for increased torsional
rigidity. This increased rigidity provides a stable base for the mixers modern
electronics. The complete chassis is formed from 0.040” aircraft aluminum. All
punching is done on a computer controlled “Strippet” rotary turret punch press for
extreme accuracy. In addition, through careful design, we have managed tolower the overall weight of the M4mkII Mixer to 3 lbs. (1.36Kg) total. A full halfpound lighter than its predecessor and lighter than any other professional fourchannel mixer in its category.
The mixers sheet metal is hand-formed using various press brake setups before
the all stainless steel threaded insert are pressed permanently into place. The
housing parts are then Chem Film TM plated for superior corrosion resistance
before being electro-statically coated with an epoxy powder coating. This
powder coat paint is then baked on in an oven. Powder coating chosen for its
durability and environmental friendly characteristics.
All silk-screening is printed sub-surface (below) a hardface lexan tm overlay.
This process provides a silk-screened label that is virtually wear proof. The
lettering will not wear off as on other mixers.
B.

ELECTRONIC TOPOLOGYThe new M4mkII audio mixer was designed from a clean sheet of paper. It
utilizes completely new circuitry designs based upon the latest advances in semi
conductor technology. In addition, it features surface mount technology for
reduced size and weight.
The M4mkII Mixer uses high quality transformers on its inputs and outputs.
Transformer topology was chosen for its inherent ability to reject RF, thus making
this new mixer perfect for use with multiple RF systems.
This new design uses modern semi-conductors from Maxim, Linear Technology
National Semiconductor, Burr-Brown and Analog Devices to name but a few.
These operational amplifiers, voltage regulators and precision voltage referencesfeature low power consumption, low noise and low distortion. The also featureability to swing from rail to rail resulting in an energy efficient design.

13

C.

ENVIRONMENTAL OPERATIONYour new M4mkII Audio Mixer has been designed to operate under extreme field
conditions. The electronics have been designed to operate over a temperature
range of -4 to 158 degrees Fahrenheit (-20 to +70C) less the affects on batteries.
This in addition to the M4mkII’s ability to operate under high humidity conditions
makes it perfect for harsh field conditions.
D.

PORTA BRACE CASE

Each PSC M4mkII Mixer is supplied with a custom-made Porta Brace case andshoulder strap. This case includes sewn on mounting rings allowing you tomount Porta Brace accessory cases such as their RF Multi case. These cases
accommodate your wireless receivers. You can call Porta Brace or any of theirauthorized dealers for the complete line of Porta Brace products.
INTERFACINGA.

TO BETACAMS:

The PSC M4mkII Mixer is especially designed for easy interfacing with all
popular Betacam type cameras. The M4MKII is equipped with a 10 pin Hirose tm
connector on the left-hand side panel. This all-inclusive connector provides bothleft and right balanced outputs and tape returns. Pin Outs are as follows:
Pin 1
Pin 2
Pin 3
Pin 4
Pin 5
Pin 6
Pin 7
Pin 8
Pin 9
Pin 10

Left Output High
Left Output Low
Right Output High
Right Output Low
Left Tape Return
Tape Ground
Right Tape Return
Tape Ground
GroundGroundThe outputs are electrically the same as the XLR outputs on the right side of themixer. Thus, the output levels can be switched to the mic or live levels.
PSC manufactures a selection of standard M4mkII Beta snake cables for use
with the new M4mkII Mixer. These cables are available in standard and camera
breakaway versions from any authorized PSC dealer. Part numbers are as
follows:
FPSC1091M4A
FPSC1091M4B
FPSC1091M4C
FPSC1091M4D

15’ (4.5M)
15’ (4.5M)
25’ (7.5M)
25’ (7.5M)
14Standard
Breakaway
Standard
Breakaway

B:

TO RDAT RECORDERS:

The M4mkII Mixer can be interfaced to virtually any professional recorder via thestandard XLR outputs. In addition, you can use the 10 pin Hirose tm connector
if you desire to use the tape return function.
C:

TO WIRELESS MICROPHONES:The M4mkII Mixer will easily accept the output signal from virtually any wirelessreceiver. It can accept microphone or line level signal via a simple switch setting.
Please note that most wireless receivers are not compatible with 48PH mic
power. You should always set the M4mkII’s mic powering switch to “D” dynamic
when using wireless receivers.
The M4mkII Mixer can also be used to send audio signals to Betacams via
wireless transmitters. The use of transmitters is normally accomplished byconnecting the M4mkII’s output XLR to the audio input of the specific transmitter.
Many transmitter manufacturers supply application specific cables for thispurpose. The M4mkII Mixer has been designed to minimize RF interference
through the use of output transformers and other RF filtering. It is important tonote that transmitter placement greatly affects transmit range and clarity. For
best results, transmitters should be mounted away from the mixers surface
allowing un-impeaded RF radiation. This can be accomplished by mounting thetransmitters up and away from the mixer on the PortaBrace Strap.
WARRANTY AND NON-WARRANTY SERVICE
In the unlikely event your M4mkII Mixer requires service it should be carefully
packed and shipped prepaid to:Professional Sound Corporation
Service Department
28085 Smyth Drive
Valencia, CA 91355 USA
PH 661-295-9395
FAX 661-295-8398
e-mail techsupport@professionalsound.com
Please call before shipping your mixer. We may be able to solve your problem
via the phone. Many older M4 and M4A+ Mixers have been shipped in to us forservice with incorrect switch settings. We are always willing to help you with your
M4mkII Mixer questions.
WARRANTY
Complete details of the PSC M4mkII Mixer warranty are
given on the enclosed blue warranty registration card. If you did not receive one,please contact your local dealer or call us directly.

15

SPECIFICATIONS
Size:

10.125” x 6.825” x 1.900”(257mm x 173mm x 48mm)

Weight:3lbs. (1.36Kg)

Temp Range:-4 to +158F (-20 to +70C)

Batteries:

NP-1 Rechargeable, any typeor 8x AA Alkaline

Case Material:

0.040” (1mm) Aircraft Aluminum

Finish:Epoxy Powder Coat

Overlays:0.005” Hardface Lexan tm with
Sub-surface Epoxy silk screening

Global Gain:

80dB at detent on master

Freq. Response:

20-20Khz +/-1dB

Signal to Noise:

128.5dB EIN 150 Ohms

Distortion:

00.08% THD

Low Cut Filter:

100Hz, 140Hz 12dB/Octave

Mic Power:

DYN, 48 PH

Oscillator:

440Hz

Limiter:

1mS Attack, 100 mS Release
2.7:1 Ratio

Warranty:

1 Year, Limited

Copyright 2002, Professional Sound Corp. This manual and the complete M4mkII
Mixer design is covered under various state, federal and international copyrightlaws. No portion of this manual or any M4mkII mixer technologies may be
reproduced without the specific written permission of PSC. All rights reserved.
This manual and M4mkII Mixer specifications subject to change without notice.

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