Behringer Eurorack MX1604A User manual

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EUsers Manual
Bedienungsanleitung D
E
EURORACK
MX1604A
Version 1.0 December 1998
www.behringer.de

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acc. to the Directives
89/336/EWG and 73/23/EWG
We, BEHRINGER INTERNATIONAL GmbH
Hanns-Martin-Schleyer-Straße 36-38
D - 47877 Willich
Name and address of the manufacturer or the introducer of the product on the market who is established in the EC
herewith take the sole responsibility to confirm that the product:
EURORACK MX1604A
Type designation and article-No(if applicable)
to which this declaration refers, is in accordance with the following standards or stan-
dardized documents:
xEN 60065 xEN 61000-3-2
xEN 55020 xEN 61000-3-3
xEN 55013
The following operation conditions and installation arrangements have to be pre-
sumed: acc. to Operating Manual
B. Nier, President Willich, 01.12.1998
Name, address, date and legally binding signature of the person responsible
EC-Declaration of Conformity
INTERNATIONAL GmbH

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This symbol, wherever it appears,
alerts you to the presence of
uninsulated dangerous voltage inside
the enclosure - voltage that may be
sufficient to constitute a risk of shock.
This symbol, wherever it appears, alerts
you to important operating and mainte-
nance instructions in the accompanying
literature. Read the manual.
SAFETY INSTRUCTIONS
CAUTION: To reduce the risk of electrical shock, do not remove
the cover (or back). No user serviceable parts in-
side; refer servicing to qualified personnel.
WARNING: To reduce the risk of fire or electrical shock, do not
expose this appliance to rain or moisture.
DETAILED SAFETY INSTRUCTIONS:
All the safety and operation instructions should be read before the appliance is operated.
Retain Instructions:
The safety and operating instructions should be retained for future reference.
Heed Warnings:
All warnings on the appliance and in the operating instructions should be adhered to.
Follow instructions:
All operation and user instructions should be followed.
Water and Moisture:
The appliance should not be used near water (e.g. near a bathtub, washbowl, kitchen sink, laundry tub, in a
wet basement, or near a swimming pool etc.).
Ventilation:
The appliance should be situated so that its location or position does not interfere with its proper ventilation.
For example, the appliance should not be situated on a bed, sofa rug, or similar surface that may block the
ventilation openings, or placed in a built-in installation, such as a bookcase or cabinet that may impede the
flow of air through the ventilation openings.
Heat:
The appliance should be situated away from heat sources such as radiators, heat registers, stoves, or other
appliance (including amplifiers) that produce heat.
Power Source:
The appliance should be connected to a power supply only of the type described in the operating instructions
or as marked on the appliance.
Grounding or Polarization:
Precautions should be taken so that the grounding or polarization means of an appliance is not defeated.
Power-Cord Protection:
Power supply cords should be routed so that they are not likely to be walked on or pinched by items placed
upon or against them, paying particular attention to cords and plugs, convenience receptacles and the point
where they exit from the appliance.
Cleaning:
The appliance should be cleaned only as recommended by the manufacturer.
Non-use Periods:
The power cord of the appliance should be unplugged from the outlet when left unused for a long period of
time.
Object and Liquid Entry:
Care should be taken so that objects do not fall and liquids are not spilled into the enclosure through openings.
Damage Requiring Service:
The appliance should be serviced by qualified service personnel when:
- The power supply cord or the plug has been damaged; or
- Objects have fallen, or liquid has been spilled into the appliance; or
- The appliance has been exposed to rain; or
- The appliance does not appear to operate normally or exhibits a marked change in performance; or
- The appliance has been dropped, or the enclosure damaged.
Servicing:
The user should not attempt to service the appliance beyond that is described in the Operating Instructions.
All other servicing should be referred to qualified service personnel.

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EURORACK
MX1604A
Ultra-Low Noise 12 Channel, 4-Bus Mic/Line Mixer
sUltra-low noise 12-channel 4-Bus Mixer
s4 mono input channels with gold plated XLRs
s4 stereo input channels
s2 additional multi-functional stereo Aux Returns
sPre and post fader Aux Sends for external effects and monitoring
sMaster Aux Sends with gain control
sExtremely high headroom - offering more dynamic range
sUltra-low noise discrete Mic Pre-amps with +48 V Phantom Power
sBalanced inputs and Main outputs
sPeak LEDs and switchable Low Cut filter on all mono channels
sUltra-musical 3-band EQ on all channels
sMute / Alt 3-4, Solo-In-Place and Pre-Fader-Listen function on all channels
sSeparate Main Mix, Control Room and Headphone outputs
s2-Track inputs assignable to Main Mix or Control Room / Headphone outputs
sHighly accurate Bargraph Meters on output
sHigh quality Panasonic 60 mm faders and sealed potentiometers
sRugged design Power Supply ensures superior transient response
sState-of-the-art 4580 ICs and high quality components ensure crystal-clear
Audio Performance and excellent noise figures
s19" Rack Mounting kit included
sExtremely rugged construction ensures long life even under the most demanding conditions
sManufactured under the stringent ISO9000 Management System

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FOREWORD
Dear Customer,
Welcome to the team of EURORACK users and thank you very much for expressing your confidence in
BEHRINGER products by purchasing this unit.
It is one of my most pleasant tasks to write this letter to you, because it is the culmination of many months of
hard work delivered by our engineering team to reach a very ambitious goal: To produce a compact mixer,
which fully satisfies your and our expectations and delivers a superior sound quality, easy operation and
technical specifications. In addition to that the mixer is affordable for almost every musician. The task to
design the EURORACK MX1604A certainly meant a great deal of responsibility, which we assumed by
focusing on you, the discerning user and musician. It also meant a lot of work and night shifts to accomplish
this goal. But it was fun, too. Developing a product usually brings a lot of people together, and what a great
feeling it is when everybody who participated in such a project can be proud of what weve achieved.
It is our philosophy to share our joy with you, because you are the most important member of the BEHRINGER
family. With your highly competent suggestions for new products youve greatly contributed to shaping our
company and making it successful. In return, we guarantee you uncompromising quality (manufactured
under the ISO9000 certified management system) as well as excellent technical and audio properties at an
extremely favorable price. All of this will enable you to fully unfold your creativity without being hampered by
budget constraints.
We are often asked how we can make it to produce such high-grade devices at such unbelievably low prices.
The answer is quite simple: its you, our customers! Many satisfied customers means large sales volumes
enabling us to get better conditions of purchase for components, etc. Isnt it only fair to pass this benefit back
to you? Because we know that your success is our success, too!
I would like to thank the following people, whose help on Project EURORACK MX1604A has made it all
possible:
sThe existing users of BEHRINGER equipment (whose comments and suggestions have made them the
most important members of the BEHRINGER design team),
sMark Devlaeminck (for this marvellous manual layout),
sBernhard (Rammi) Ramroth (whose technical ingenuity is unique),
sC.W. for the fine mechanics (key-phrase Tooling modification)
sand all the others, who have made very personal contributions.
My friends, its been worth the effort!
Thank you very much,
Uli Behringer

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TABLE OF CONTENTS
1. INTRODUCTION ...................................................................................................................... 8
1.1 Architecture .................................................................................................................................... 8
1.2 Before you begin ............................................................................................................................ 9
1.2.1 PSU (Power Supply Unit) ..................................................................................................... 9
1.2.2 Warranty .............................................................................................................................. 9
1.2.3 Packing ................................................................................................................................ 9
1.2.4 Rack mounting the MX1604A ................................................................................................ 9
2. MONO INPUT CHANNEL ......................................................................................................... 9
2.1 Input level setting .......................................................................................................................... 10
2.2 Equalizer ...................................................................................................................................... 10
2.3 Aux Sends .................................................................................................................................... 10
3. STEREO INPUT CHANNEL ................................................................................................... 11
3.1 Input level setting ...........................................................................................................................11
3.2 Equalizer .......................................................................................................................................11
3.3 Aux Sends .....................................................................................................................................11
3.4 Routing ..........................................................................................................................................11
4. MAIN SECTION ...................................................................................................................... 11
4.1 Aux Sends .....................................................................................................................................11
4.2 Stereo Aux Returns ........................................................................................................................ 11
4.3 Metering ....................................................................................................................................... 12
4.4 Channel mode .............................................................................................................................. 12
4.5 2-Track input and output ............................................................................................................... 12
4.6 Monitoring ..................................................................................................................................... 13
4.7 Alt 3-4 output ................................................................................................................................ 13
5. SETTING UP .......................................................................................................................... 14
5.1 Desk normalization ....................................................................................................................... 14
5.2 Selecting inputs ............................................................................................................................ 14
5.3 Initializing channels for gain setting .............................................................................................. 14
5.4 Auditioning a signal and setting up a channel ............................................................................... 14
5.5 Multitrack initialization ................................................................................................................... 15
5.6 Recording levels ........................................................................................................................... 15
5.7 Track sheet ................................................................................................................................... 15
6. APPLICATIONS ..................................................................................................................... 15
6.1 Keyboard mixing, live or in the studio............................................................................................ 15
6.2 Live gig with simultaneous 2-TK recording ....................................................................................16
6.3 MIDI Project studio  laying vocals to tape .................................................................................... 17
7. SOME MIXING TOPICS ......................................................................................................... 18
7.1 Equalization .................................................................................................................................. 18
7.2 Gain optimization .......................................................................................................................... 19
8. CONNECTIONS ..................................................................................................................... 19
8.1 EURORACK MX1604A connections .............................................................................................. 19
8.2 Connections ................................................................................................................................. 20
8.3 Looming problems ........................................................................................................................ 22

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9. APPENDIX ............................................................................................................................. 23
9.1 Specifications ............................................................................................................................... 23
9.2 Front & back panels ...................................................................................................................... 24
9.3 Block diagram ............................................................................................................................... 25
9.4 Modifications ................................................................................................................................ 26
9.5 Expanding ..................................................................................................................................... 26
9.6 Glossary ....................................................................................................................................... 27
10.WARRANTY ........................................................................................................................... 29

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1. INTRODUCTION
Congratulations. In purchasing our EURORACK you have acquired a mixer whose small size belies its
incredible versatility and audio performance. Your EURORACK is built to the same outstanding quality as our
top-of-the range console, the BEHRINGER EURODESK MX9000.
Later we will see how adding the BEHRINGER ULTRALINK PRO MX882 to your system can inexpensively
expand the capacity and flexibility of you mixing power even further. First of all, however, we want to take you
on a guided tour of your new rack-mounted console - the BEHRINGER EURORACK MX1604A.
We recommend that you experiment with your EURORACK away from the pressures of a recording session
or live concert, in order to get a feel for it. It is a musical instrument. Learn to play it well.
Next to the specifications you will find some pages with drawings showing the front and rear panel of your
EURORACK respectively. Keep them turned over, laying to the left of the text pages, while studying the
manual.
All functions will be numbered consistently throughout the manual, whether they be in the text or on an
illustration.
Most specialist subjects are not really all that difficult provided you understand the language used, and the
vocabulary of mixing is pretty straightforward. Nevertheless it is as well to be clear about what certain terms
mean. A slot in a recorder will always be referred to as a track, while that in a mixer will invariably be a
channel. I will attempt to be as unambiguous as possible with terms, since much confusion can arise from
sloppy definitions. If a new term (to you) does arise, and it isnt fully explained in the text, try to look it up in the
Glossary before you write a letter of complaint!
1.1 Architecture
Mono input channels
Channels 1 - 4 are mono, with a choice of balanced Mic or Line inputs. The vintage-style high-current
discrete Mic amps are of the same incredible quality as those found on the acclaimed BEHRINGER EURODESK
MX9000, while a large external Power Supply ensures low noise and superior transient response at all times.
Stereo input channels
A further 8 Line inputs on the MX1604A are configured as 4 stereo input channels. These are ideal for
multitrack tape returns, or for accepting outputs from MIDI and other electronic instruments.
Channel outputs
A high-quality true logarithmic 60 mm fader feeds the Main Mix or Alt 3-4 bus via the channel Pan.
Aux Sends
There are two Aux Send buses on the MX1604A.
Stereo Aux Returns (stereo Line inputs)
The stereo Aux Returns lie directly above the master Aux Sends. These can be routed to the cue send (i.e.
Aux Send 1 set to pre-fader) directly by pressing , in order to enable performers to get a wet foldback
mix. The Aux Returns may also be used for mixing in extra MIDI instruments etc.
Main Mix output
Main Mix output level is via a pair of high-quality true-log 60 mm stereo faders and is monitored by a pair of
accurate 12-segment bargraph peak meters, surrounded by 4 status LEDs.
In addition, your MX1604A provides an adjustable Phones output, a separate 2-Track in-/output and the
above-mentioned Alt 3-4 output.
Meters
Channels 1 - 4 have overload LEDs, while the L and R outputs have 12-segment bargraph meters. The L/R
meters double up as mono PFL or stereo Solo meters. The meters should average around 0 dB during loud
passages. If they read persistently higher, or are peaking above +10 dB, reduce either the main L/R faders
and/or channel faders, or channel input gain. Perhaps the PFL sequence should be repeated.
1. INTRODUCTION

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The configuration is 16 into 4 (2+2) into 2. There are four mono channels, four stereo channels and two
stereo Aux Returns. In addition there is a 2-Track input routable to the Main Mix. A channel is always routed
to the Main Mix outs unless Alt 3-4 is selected, in which case its signal is sent to outputs 3 and 4 instead.
Outputs 3 and 4 may be blended with the Main Mix at the Control Room output via a switch . Beside
that the Alt 3-4 signal can also be fed into the Main Mix by pressing Alt 3-4 To Mix. .
1.2 Before you begin
1.2.1 PSU (Power Supply Unit)
Any amplifier circuit is limited in its transient response by the available current. Every mixer has numerous
Line level operational amplifiers (op-amps) inside. When being driven hard, many desks begin to show signs
of stress due to power supply limitations. Not so with the EURORACK MX1604A. The sound will always stay
clean and crisp right up to the operating limits of the op-amps themselves, thanks to our generous 40 W
external Power Supply Unit.
+Do not connect the PSU to the EURORACK while the PSU is connected to the mains supply.
Connect switched-off desk and PSU first before you connect the PSU to the mains supply.
Lastly switch on desk by on the back panel. Use only the correct BEHRINGER power
supply unit to connect the MX1604A to the mains (see Chapter 9.1 Specifications for details).
1.2.2 Warranty
Please take time to have the warranty card filled out completely by your authorized dealer and return it within
14 days after the date of purchase, so as to be entitled to benefit from our extended warranty.
1.2.3 Packing
Your BEHRINGER MX1604Awas carefully packed in the factory and the packaging was designed to protect
the unit from rough handling. Nevertheless, we recommend that you carefully examine the packaging and its
contents for any signs of physical damage which may have occurred in transit.
+If the unit is damaged, please do not return it to us, but notify your dealer and the shipping
company immediately, otherwise claims for damage or replacement may not be granted. Ship-
ping claims must be made by the consignee.
1.2.4 Rack mounting the MX1604A
Enclosed in the shipping box you will find a rackmount kit. If you want to make your MX1604A a rack mixer,
losen the screws on the side panels and use them to fix the rack ears (note, that there is a left and a right
one).
+Be sure that there is enough space around the unit for cooling and please do not place the
MX1604A on high temperature devices such as power amplifiers etc. to avoid overheating.
+When switched on, parts of the desk and the power supply unit will become very warm, this is
normal during operation.
2. MONO INPUT CHANNEL
Each channel is equiped with a balanced Line input 1/4" jack socket and an XLR Mic input .
Phantom powering is switchable from the back panel .
Note: When using the Mic input please make sure nothing is connected to the same channels Line input, and
vice versa.
The gain circuit has an unusually wide range, obviating the need for Mic/Line switching. The crucial operating
levels +4 dBu and -10 dBV are clearly and accurately marked .
2. MONO INPUT CHANNEL

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2.1 Input level setting
Channel input level is determined by the Gain control . Use Solo/PFL to bring the channel input onto
the left and right bargraph meters respectively. This also sends the Solo/PFL-ed signal to the left and
right speakers.
For level-setting (as opposed to localized listening) select the mono PFL bus rather than the post-fader (post-
channel pan) stereo Solo bus (Channel Mode global switch up).
Solo/PFL never interrupts the mix at the main recording outputs. It follows that Aux Sends must also be
unaffected, since they contribute directly to the Main Mix.
In addition to switchable Solo/PFL metering, a channel LED illuminates when a channel is going into
overload. You do not want the overload light to come on except very intermittently during a take or a mix. If it
does light persistently, reduce input gain (see also Section 5: SETTING UP).
There is a steep Lo Cut (high pass) filter , slope at 18 dB/oct., -3 dB at 75 Hz, for reducing floor rumble,
explosives, woolly bottom end etc.
2.2 Equalizer
All mono input channels are fitted with three-band EQ and the above mentioned switchable Lo Cut filter for
eliminating unwanted subsonics. All three bands have up to 15 dB of cut and boost, with a centre detent for
off.
The upper , mid and lower shelving controls have their frequencies fixed at 12 kHz, 2.5 kHz and
80 Hz respectively.
2.3 Aux Sends
Both Aux Sends are mono and post-EQ. Aux Send 1 can be taken from a point before or after the
channel fader, i.e. pre or post by . Aux Send 2 is always wired post-fader.
For almost all FX send purposes, you will want Aux Sends to be post-fader, so that when a fader level is
adjusted, any reverb send from that channel follows the fader. Otherwise, when the fader is pulled down, the
reverb from that channel would still be audible. For cueing purposes, Aux Sends will usually be set pre-fader,
i.e. independent of the channel fader and mute.
Most reverbs etc. sum internally the left and right inputs. The very few that dont may be driven in true stereo
by using 2 Aux Sends.
There is +15 dB of gain on every Aux Send. Such a high boost is usually only appropriate where the channel
fader is set around -15 dB or lower. Here, an almost exclusively wet signal will be heard. In most consoles,
such a wet mix requires the use of a pre- setting for the channel Aux Send, losing fader control. With the
EURORACK you can have a virtually wet mix with fader control.
+Mono channels may be altered for pre-fader Aux 2 (see Chapter 9.4 Modifications).
2. MONO INPUT CHANNEL

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3. STEREO INPUT CHANNEL
Each stereo channel comes with two balanced Line level inputs on 1/4" TRS jacks, for left and right signals.
When only the left input is connected, the channel operates in mono.
3.1 Input level setting
The stereo inputs are designed for any Line level signal. Most Line level sources such as MIDI instruments
and FX units will have their own output level control. Those that dont, for example CD players, all have an
output level within the scope of the MX1604A. When the channel and master fader are set to unity gain the
meters should read between -4 and +7 dB. Remember that there is 15 dB gain on both the channel as well as
master fader.
3.2 Equalizer
The stereo input channels are fitted with three-band EQ. The equalizer is has exactly the same parameters as
on the mono channels, in stereo. A stereo equalizer is generally preferable to using two mono equalizers
when EQ-ing a stereo signal, as often discrepancies between left and right settings can occur.
3.3 Aux Sends
These are the same as for mono channels (see 2.3). Note that a mono sum is taken from the stereo input.
3.4 Routing
When a channel is run in stereo, this control functions as a Balance control, determining the relative balance
of the left and right channel signals being sent to the left and right Main Mix buses. For example, with the
Balance control turned fully clockwise, only the right portion of the channels stereo signal will be routed to the
Main Mix.
Balance also determines the relative amount of left and right channel signals being sent to buses 3 and 4
respectively when Mute / Alt 3-4 is engaged.
4. MAIN SECTION
4.1 Aux Sends
Master Aux Send levels are determined by and . These controls have a centre detent indicating unity
gain. Dont worry if your effects unit has no input gain control  you have a further +15dB available from
these outputs.
4.2 Stereo Aux Returns
There are two additional stereo Line inputs (Aux Returns 1 and 2) on your MX1604A. Aux Return 1 is
permanently assigned to the Main Mix. If you connect a jack to the left socket only, the Aux Return 1 operates
in mono. Aux Return 2 can be switched between the Main Mix and the cue feed (Aux Send 1) via a switch
marked FX TO AUX 1 . This enables you to provide a wet (signal with effect i.e. reverb) cue mix for the
headphones or foldback speakers.
3. STEREO INPUT CHANNEL

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If no connection is made to Aux Return 2, the signal is normalled (connected directly) to Aux Return 1.
Depressing FX TO AUX 1 will then feed the signal from Aux Return 1 into the cue feed (Aux Send 1) and can
be controlled in level independently with Aux Return 2. This feature is primarily useful when you are using one
effect for the Main Mix and for the foldback speakers.
+When using Aux Send 1 as a second (pre-fader) effects send and Aux Return 2 as the effect
input, do not engage FX TO AUX 1 . The connection from Aux Return 2 to Aux Send 1 could
cause feedback.
However, there are exceptions: For instance if you deliberately want to send one effect into another, e.g.
delay into chorus etc.
The Aux Returns are multi-functional. They may be used for returning the outputs of effect units. You can use
them as Tape Returns from a multitrack recorder. They may also be used as extra instrument inputs, espe-
cially if your MIDI keyboard or rack supplies a pre-mixed stereo signal.,
Certain stereo effects produce a perceived imbalance between the left and right channel levels. To correct for
this you will have to bring your stereo effect back on a stereo channel, which has a Balance control.
When applying short left and right delays, the shortest one will always seem loudest. When pitch shifting up
and down in wide stereo to thicken a sound, the signal shifted upwards will seem louder than one that goes
down. In both cases use the Balance control to compensate (an analogy comes from Greece: the
columns of the Parthenon in Athens are slightly bowed so as to appear straight.)
When carrying any stereo imaging exercise, dont just rely on the control room monitors. Get a pair of
headphones and listen in stereo and in reverse stereo, just in case you have any significant hearing discrep-
ancies between your ears.
Sometimes an engineer wants to narrow the stereo width of a reverb field. To do this you will have to come
back on two mono channels to get independent pan for the left and right signals.
4.3 Metering
Main Mix/Solo/PFL level is displayed on a pair of highly-accurate 12-segment bargraph peak meters .
Additional LEDs indicate Power On , +48 V Phantom Power present , and whether the mono Pre-
Fader-Listen bus or the stereo Solo bus is engaged.
4.4 Channel mode
The Channel Mode switch determines whether Solo-In-Place or Pre-Fader-Listen is assigned to the
channel Solo buttons.
Solo
Solo is the preferred method for auditioning an isolated signal, or group of signals. Whenever a Solo button is
pressed, all unselected channels are muted in the monitors. Stereo panning is maintained. The Solo bus is
derived from the output of the channel Pans, Aux Sends and stereo Line inputs. It is always post-fader.
PFL
Pressing once disengages the stereo Solo bus, and replaces it with a separate mono PFL (Pre-Fader-
Listen) bus. All Solo signals are reconfigured to PFL. PFL should always be used for gain-setting (see also
the essential Section 5 SETTING UP).
The L/R meters follow whatever source is being auditioned (the meters wont make much sense if more
than one source is selected!). Selecting Solo/PFL does not affect the signal from the L/R recording outputs.
Just as well, or every time you wanted to do a quick Solo check during a mix, youd have to start again!
4.5 2-Track input and output
Input
A 2-Track input, on RCA phono jacks , provides easy connection to DAT and other professional or semi-
professional audio equipment.
The 2-Track input is primarily for auditioning mix playback from tape. 2 TK TO CONTROL ROOM routes
4. MAIN SECTION

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this signal to the monitors and/or phones.
However, it can also be routed to the Main Mix via 2 TK TO MIX and will act as an additional input for
tape playback, MIDI instruments etc. Here should be disengaged, or you will be listening to the 2-Track
signal twice over!
With depressed you have another stereo Line input available to the mix, useful e.g. for adding the output
of a second EURORACK or a BEHRINGER ULTRALINK PRO MX882 to your mix (see Section 9.5 Expand-
ing).
Output
The Main Mix output is delivered by XLR connectors and TRS jacks on the back panel as well as by RCA
phono jacks on the front. Level is ultimately determined by a pair of precision faders .
Although the 2-Track output is primarily designed for recording, it can also be used as a PA feed, or as a
send to the input of your sampler. Depressing on the rear panel will lower the level at the XLR connectors
by 20dB.
4.6 Monitoring
Though most of you will want to audition the Main Mix most of the time there are exceptions. These
include the Alt 3-4 bus and 2-Track playback .
A single volume control sends the level to the headphones and main monitors .
If you want to audition external sources very often, you could connect a hi-fi pre-amp (or tape out) to your
2-Track input, allowing you to monitor a variety of extra sources such as vinyl, cassette, CD etc.
4.7 Alt 3-4 output
By depressing the Mute button a channels output will be routed to the Alt 3-4 output instead of the Main
Mix.
Level to the Alt 3-4 outputs (TRS jacks on the back panel) is adjusted by . Use to have the Signal
PFL-ed ( and up).
Alt 3-4 is likely to bewilder newcomers. We want to illustrate how this feature may be used most effectively.
Subgroups are commonly used as a mixing aid both live and in the studio, e.g. to combine the outputs from all
drum channels onto just 1 or 2 submaster faders. They are also used to route to multitrack recorders .
There are no fully-fledged subgroups on the MX1604A. However, the Alt 3-4 bus offers you a second
independent stereo submix with its own submaster stereo fader . Combining the Alt 3-4 outputs with the
Main Mix may be effected by activating the Alt 3-4 to Mix switch .
E.g.: If you want to generate two mono subgroups in addition to the normal Main Mix stereo bus, patch Alt outs
3 and 4 back into two mono channels, and use these as Subgroup masters (the subgroup return channels
must not be routed to the Alt 3-4 bus themselves, as this would constitute a feedback loop). Engaging mute on
any input channel routes to the Alt 3-4 bus. Channel Pan now selects between Alt outputs 3 and 4 (left = 3,
right = 4).
ALT 3 Out
ALT 4 Out Channel Line 1 Input Channel Line 2 Iinput Main Mix Main Mix
Using Channels 1 and 2 as Mono Subgroup Master
Fig. 4.1: Subgroup as Master
+Subgroups can be mixes of several channels of sound: dont be surprised if, once you have set
up the input gain correctly, the submaster faders are set higher than normal channels.
4. MAIN SECTION

14
Remember that when Alt 3-4 is in use, you do not have a channel mute facility on your desk: you will have to
pull down the fader to silence any channel.
5. SETTING UP
5.1 Desk normalization
All board settings should be set to the normal default condition before or after every session. Usually faders
are set to zero (minus infinity) EQs set flat and switched out, trimpots and channel Aux Sends turned fully
counter-clockwise etc. Many controls have a natural initial setting. For EQ cut and boost this is centre
position. However, some settings, such as selecting pre or post for channel Aux Sends, will depend on the
operating environment (e.g. studio or live), or on a particular engineers preferred way of working.
5.2 Selecting inputs
1) Mono channels accept Mic or line inputs. If you are using the Mic input, make sure nothing is connected
to the Line input (and vice-versa).
+The Mic inputs are more sensitive than the Line inputs. Do not connect mics with Phantom
Power switched on. Never use unbalanced mic cables with the Phantom Power switched on
ever!!! Shorting 48 V to earth can cause serious damage.
2) Stereo channels accept -10 dBV or +4 dBu Line level signals. Any stereo channel can be run in mono
simply by connecting into the left jack socket only. These channels are suitable for a variety of line-level
sources including MIDI instruments and Tape Returns from multitrack.
3) Stereo Line inputs are primarily designed for returning effects units, though these too may be given over
to multitrack returns or MIDI instrument outputs.
5.3 Initializing channels for gain setting
1) Set Gain to minimum and all Aux Sends to off (fully counter-clockwise).
2) Set EQ to flat (all knobs at 12 oclock).
3) Where applicable, set Lo Cut switch ON for most mics, OFF for signals with desired very low
frequency content.
4) Set channel mode to PFL .
5) Depress Solo/PFL switch.
5.4 Auditioning a signal and setting up a channel
1) Provide an input signal i.e. roll the tape. There should also be some activity at the main L/R bargraph
meters , indicating the PFL level.
2) For Mic/Line inputs: Adjust the Gain control until transient peaks are regularly hitting +6 dB. Continu-
ous signals should not exceed 0 dB.
3) For stereo Line inputs: Adjust the sources output Gain until transients are regularly hitting +6 dB. Continu-
ous signals should not exceed 0 dB.
4) If EQ is used, repeat steps 1 - 3.
5) If an insert is used to patch in a compressor, gate, EQ etc., use the outboard processors bypass or effect
off switch to A/B monitor the effect. If it does not have a bypass switch or equivalent, you will have to keep
connecting and disconnecting the device until you complete the following procedure: Adjust the processors
output level so that effected and bypassed signals are of comparable level, i.e. unity gain.
6) Solo/PFL switch UP. Move onto next channel.
5. SETTING UP

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5.5 Multitrack initialization
Set up the multitrack so that any track in record ready condition has its input monitored when the tape is
stationary. Place all tracks to be recorded into record ready status. (Once a recording has been made,
these tracks should automatically switch to tape playback). Check that the input levels to each track are
optimized before recording commences.
5.6 Recording levels
When recording to digital, its a good idea to keep the recorders peak meters below 0 dB. Most (not all, esp.
samplers) read 0 dB with some headroom left. This is because, unlike with analogue, the onset of digital
distortion is as sudden as it is horrible. If you really want to take your recording level to the limit (and fully
exploit for instance 16-bit digitals 96 dB dynamic range), youll have to do some calibrating. How to do it?
Well, you could run a tone at 0 dB from the mixer and use that as your DAT or digital multitrack recorder
reference. But your DAT or multitrack recorder may be way under its maximum input limit. Probably a better
way to work out just how hard you can drive your recorder is to incrementally increase the record level until
the onset of digital distortion, subtract, say, 5 or 10 dB, and never exceed that level. Engage peak hold on
your recorder before recording if you want to confirm that you havent.
When recording to analogue, the tape machines VU meters should show around +3 dB on bass, but only
around -10 dB for hi hat. Although analogue distortion is more like compression at modest overload levels
(often desirable on bottom end), higher frequencies cause saturation even at modest levels (resulting in an
unpleasant crunchiness). Also, VU meters tend to progressively under-read above 1 kHz, due to their
sluggish response time. Hi-hats should read about -10 dB on a VU meter, as against 0 dB for a typical snare
drum, and +3 dB or more for a kick drum.
Peak meters read more-or-less independent of frequency. Aim for 0 dB recording level for all signals.
5.7 Track sheet
When laying out channels for recording or mixing, try to be sensible. Keep tom-toms together, etc. Work out
a scheme that suits you and stick to it. A common order is: kick drum, snare, hi-hat, tom-toms (as the
audience sees the kit), cymbals (ditto), bass, guitars, keyboards, other instruments, vocals. From session to
session and gig to gig you will soon know where you are without hardly ever having to look at your track-
sheet.
6. APPLICATIONS
Experience tells us that the cables in a studio environment get tangled very quickly (inviting mistakes). A
patchfield will facilitate patching and repatching considerably. The BEHRINGER ULTRAPATCH PRO PX2000
makes patching easier and trouble free, increasing both ergonomics and productivity.
6.1 Keyboard mixing, live or in the studio
This is relatively simple to achieve. Simply use the Line inputs to mix stereo or mono outputs from your
keyboards. It may be useful to use the Alt 3-4 outs e.g. to control the level of drums versus music. Aux Sends
may be used either to feed on-stage monitors, artists headphones or effects units. The Main Mix output
should feed the FOH or studio mixer. A typical comprehensive live setup is shown below.
6. APPLICATIONS

16
Keyboard mixing
Source Mic/Line Mono/Stereo Input
MIDI instrument #1 Line Mono 1
MIDI instrument #2 Line Mono 2
MIDI instrument #3 Line Mono 3
MIDI instrument #4 Line Mono 4
MIDI sampler #1 Line Stereo 5-6
MIDI sampler #2 Line Stereo 7-8
MIDI synth #1 Line Stereo 9-10
MIDI synth #2 Line Stereo 11-12
Effects unit #1 Stereo Aux 1
Effects unit #2 Stereo Aux 2
Aux out 1 > Effect (post-fader)
Aux out 2 > Effect (post-fader)
Main Mix out L > Compressor > FOH
Main Mix out R > Compressor > FOH
Monitor out L > Personal foldback (main stereo feed)
Tab. 6.1: MX1604A Example Keyboard mixing
6.2 Live gig with simultaneous 2-TK recording
Here some or all mono channels are likely to be tied up with stage mics. Carefully position these so as to
minimize feedback. Try to keep the stage volume as low as possible, as stage sound can interfere with and
muddy FOH sound, as well as causing a reduction in feedback thresholds. Dont forget to notch out trouble-
some frequencies using a Graphic or Parametric Equalizer, or Feedback Destroyer (see the BEHRINGER
ULTRA-CURVE PRO DSP8024 or the FEEDBACK DESTROYER PRO DSP1100P, which do all of these and
more).
Use the Lo Cut filters to eliminate floor rumble, mics popping etc.
Live Gig with 2-TK Recording
Source Routing Mic/Line Mono/Stereo Input
Vocals Main Mix Mic Mono 1
Backing Vocals Main Mix Mic Mono 2
Bass Drum Alt 3-4 Mic Mono 3
Drum Overhead Alt 3-4 Mic Mono 4
Guitar Alt 3-4 Line Stereo 5-6
Bass Alt 3-4 Line Stereo 7-8
Keyboard #1 Main Mix Line Stereo 9-10
Keyboard #2 Main Mix Line Stereo 11-12
Effects Stereo Aux 1
Intro Tape Stereo Aux 2
Alt 3-4 out (Instruments) > 2-Track input
Aux out 1 > Cue 1 (pre-fader)
Aux out 2 > Effect (post-fader)
Main Mix out L > Recording (DAT L)
Main Mix out R > Recording (DAT R)
Monitor out L > Graphic EQ > FOH
Monitor out R > Graphic EQ > FOH
Tab. 6.2: MX1604A Example Live gig with 2-TK recording
Switching logic for this setup is: and up, and down and down for channels 3 - 8.
6. APPLICATIONS

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6.3 Project studio  laying vocals to tape
8-track MIDI project studio with sampler, 8-track recording system, one vocal mic and two effects units:
Project Studio, laying vocals to tape
Source Routing Mic/Line Mono/Stereo Input
Vocals Alt 3-4 M Mono 1
Tape Main Mix L Mono 2
Tape Main Mix L Mono 3
Tape Main Mix L Mono 4
Sampler #1 Main Mix L Stereo 5-6
Sampler #2 Main Mix L Stereo 7-8
Sampler #3 Main Mix L Stereo 9-10
Sampler #4 Main Mix L Stereo 11-12
Effects #1 Stereo Aux 1
Effects #2 Stereo Aux 2
MX 882 Mix out > 2-Track input (S33 up, S36 down)
Alt 3-4 out > available for track-laying
Aux out 1 > Effect 1
Aux out 2 > Effect 2
Main Mix out L > Recording (DAT L)
Main Mix out R > Recordin
g
(DAT R)
Monitor out L > Control Room / Headphone amp
Monitor out R > Control Room / Headphone amp
Tab. 6.3: MX1604A example "Project studio, laying vocals to tape"
Switching logic for this setup is: and up, , and down, down in channel 1.
With largely computer-generated music you will want to have plenty of line inputs, and an ability to take vocals
quickly, efficiently, and with minimal desk disturbance. Often a vocal line is added after the music is almost
complete. For this we try not to use a valuable Aux Send as a cue feed. In general, the mix in the artists
headphones can be the same as that going into the control room monitors: basically a stereo mix with 1) the
vocal channel raised above the mix level in volume and 2) any off-putting channels muted.
If you intend to take several tracks in quick succession, you can route the channel via the Alt 3-4 bus
simultaneously into all tape tracks via a simple junction box, splitter lead, line mixer like our MX882, or
patchbay.
Note: When using Alt 3-4 to send to tape, you can either audition the signal via the tape recorder track, or by
assigning Alt 3-4 to the control room monitors , or both. If you are auditioning the vocalist via both routes,
the voice should appear louder to you (and the singer) during a take, but be set properly in the mix during
playback. By a benign twist of fate, this is usually exactly what you (and they) want.
Note that there are 2 Aux Sends and 2 stereo Aux Returns. If you want to use more than 2 effects units, these
can either be 1) patched across insert points, 2) inserted between the samplers outputs and desk inputs, or
3) driven from the channel insert. If you have invested in the 8-channel BEHRINGER ULTRALINK PRO
MX882 for tape monitoring purposes, you can turn the 2-TK input into 8 line inputs for accepting stereo or
mono effects or synths etc. during mixdown.
6. APPLICATIONS

18
Fig. 6.4: Project studio setup example
7. SOME MIXING TOPICS
7.1 Equalization
The variable parameters of the channel equalizers on the EURORACK are described in sections 2.2 and 3.2.
Few people buying a mixer will need to be told how an Equalizer works. But how to get the best out of it? Well,
thats another story. In the beginning EQ was an instrument for removing unwanted frequencies, or compen-
sating for imperfect microphone response curves, or bumps in a studios acoustic. It was a corrective device.
Tamla Motown turned that notion upside down in the sixties with the novel idea that you try to find for each
instrument a characteristic frequency not shared by the other instruments in the mix. Then you whack up its
gain. This makes individual voices punch through a mix in a slightly unnatural but exciting way.
In general corrective EQ usually involves broadband (slope) contouring, together with narrowband notching
of unwanted resonances. The narrower the notch or Q, the less the total signal will be affected. Finding bad
resonances is made easier by first frequency sweeping in BOOST mode.
Motown EQ is achieved by applying boost in a fairly broadband way. The broader the band, the more
musical but less instrument-specific the effect. Applying boost over a narrow bandwidth will sound honky.
For sounds which require drastic corrective EQ, it is advisable to have a couple of channels of fully compre-
hensive Parametric Equalization in your rack. (You can always bounce tracks though the outboard EQ,
freeing up the unit for the next task).
Check out the BEHRINGER ULTRA-CURVE PRO DSP8024, a superlative digital stereo Equalizer and much,
much more. Or our ULTRA-Q PRO PEQ2200 5-band Constant-Q state-variable analog EQ.
For Advanced Equalization, EQ might be applied to a signal as follows: First, trim the LF and HF shelves to
achieve the required slope or loudness. Now use a Parametric EQ band to boost the most significant
frequency for each instrument or tape track. Over all channels, if two or more of these frequencies coincide,
then you might have to settle for second best in some cases, if you want to achieve optimum separation in the
mix. Really nasty frequencies will need notching out.
7. SOME MIXING TOPICS

19
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A good vocal signal can be enhanced by applying a significant boost in the 12 kHz region or higher, above
the nasty sibilance region. This is especially effective if youve got a de-esser patched post-EQ.
+Use the Lo Cut to tighten up channels in a mix: maybe remove it only for the bass, kick drum,
toms, tablas, didgeridoo and other deliberate subsonics (when recording classical music ig-
nore this advice).
With the LF set to boost, and the Lo Cut switch activated, you have pretty much got a peak response rather
than shelving at the bottom. Good for tight but deep bass.
Remember EQ contouring can be done with cut as well as with boost. Cutting away the top and bottom, then
pushing up the Gain is equivalent to mid range boost! EQ is not a one way street!
Always reset a channels input Gain (or external devices output level) after altering the amount of desk EQ cut
or boost applied.
7.2 Gain optimization
PFL (Pre-Fader Listen) is the way to set a desk level. Setting up the channel input Gain is discussed in the
essential section 5. Master Aux Send levels are fixed at Unity Gain. As the mix progresses, more and more
channels are likely to be sending to effects via the Aux buses, and its best to PFL all sends just before setting
up for the final mix.
Outboard reverbs etc. should all be made to work hard. Theres no point in having an 85 dB dynamic range if
the input meter of your reverb is barely flickering. On the other hand, digital distortion is not one of the nicer
noises around. Youll have to rely on your ears to detect digital distortion, since different outboard processors
calibrate their meters differently.
If you hear distortion, turn down the input on the FX unit, and turn up the desks Aux Return input.
99 times out of 100 distortion in the Aux Send / FX / Aux Return loop will come from the FX unit (FX gain too
high), and the same goes for a high noise level (FX gain too low).
Noisy FX (or synth) returns can be greatly improved by the addition of single-ended noise reduction between
FX output and Aux (or channel) Returns. The BEHRINGER DENOISER SNR2000 is ideally suited for this
purpose.
Ive found that using analogue single-ended noise reduction can help warm the sound of certain digital
reverbs which sound too cold/metallic, and also give that Echoplex sound to digital delay decays.
Analogue multitrack tape should be driven quite hard, since its dynamic range (without noise reduction) is
likely to be 20-30 dB worse than other elements in the recording chain. Try to record bright. You can always
mix back duller. Brightening up an off-tape signal will bring up the level of tape noise. With digital tape or hard
disk you have plenty of dynamic range, and treble pre-emphasis is not often necessary. Just dont let the
signal distort!
When mixing or recording, keep the channel fader levels around or below 0 dB. If you do find the faders
creeping up or down, apply a suitable offset over all channel faders, and try to control your bad habit in
future!
8. CONNECTIONS
8.1 EURORACK MX1604A connections
Follow us on a walk along the rear panel of your EURORACK, starting left:
AC Power In.
For connecting the mixer to the Power Supply Unit (PSU). Always connect mixer and PSU before you
connect the PSU to the mains supply.
Power switch
Once the PSU is connected to the mains supply, you may switch on your EURORACK. Allow 1 minute
after powering up for the system to equilibrate before setting input gains.
8. CONNECTIONS

20
Phantom Power switch
When using capacitor mics, +48 V DC can be switched globally on or off for all mic channels
(also see Mic inputs).
+Care should be taken not to plug mics into the console (or stagebox) while the Phantom Power
is on. Also, mute the Monitor/PA speakers when turning Phantom Power on or off.
Lets now have a look an all the inputs and outputs on the EURORACK. Most of them are balanced.
Unbalanced equipment may be connected to balanced inputs/outputs. Either use mono 1/4" jacks or connect
ring and sleeve of TRS jacks (or leave pin 3 of XLR plugs unused).
Main outputs (XLR)
Balanced XLR, wired pin 1 ground/screen, pin 2 hot (+ve), pin 3 cold (-ve). Maximum level is +28 dBu.
Main output level switch
Level to the XLR Main outputs (+4 dB) will be lowered to mic level, if you depress . E.g. you can
route the lowered output signal directly to the Mic inputs of another console.
Main output (TRS sockets)
Unbalanced 1/4" TRS sockets, wired tip = signal, sleeve = ground/screen.
Alt 3-4 output
Unbalanced 1/4" TRS sockets, wired tip = signal, sleeve = ground/screen.
Serial Number
Please take the time to make a note of the Serial Number in the space provided on the enclosed
Warranty Registration Card. Put the instruction manual in a safe place and return the completed
Warranty Registration Card to us within 14 days of purchase, making sure that the dealer stamp has
been acquired. Note that the warranty becomes invalid, if the original serial number has been removed
or altered (you should already pay regard to this while buying new equipment).
Let us now move onto the front panel of your EURORACK MX1604A.
Mono input channels 1 - 8
Mic inputs
Balanced XLR, wired pin 1 = ground/screen, 2 = hot (+ve), 3 = cold (-ve). Remember the Phantom
Power switch .
Line inputs
Balanced 1/4" TRS sockets, wired tip = hot (+ve), ring = cold (-ve), sleeve = ground/screen.
Stereo input channels 9/10 - 15/16
Four stereo pairs. Balanced 1/4" TRS sockets, wired tip = hot (+ve), ring = cold (-ve), sleeve = ground/
screen.
Stereo Aux Returns 1/2
Two stereo pairs. Unbalanced 1/4" TRS sockets, wired tip = signal, sleeve = ground/screen.
Aux Sends 1/2
Unbalanced 1/4" TRS sockets, wired tip = signal, sleeve = ground/screen.
2-Track in / out
RCA sockets for use with tape recorders etc., signal = Main Mix.
Control Room outputs
Will feed a pair of speakers (via an amp, of course unbalanced 1/4" TRS sockets, wired tip = signal,
sleeve = ground/screen.
Phones outputs
Will feed headphones. 1/4" TRS socket, wired tip = left signal, ring = right signal, sleeve = ground/
screen.
8.2 Connections
You will need a lot of cables for different purposes - see the following figures to make sure you have got the
right ones. Unbalanced equipment may be connected to balanced inputs/outputs. Either use mono 1/4" jacks
or connect ring and sleeve of TRS jacks.
8. CONNECTIONS