Podium Pro Audio MX1204 User manual

Podium Pro Audio
Audio at its highest level
http://www.podiumproaudio.com
© 2010
Podium Pro Audio
Model MX1204
12 Channel 4 Bus Mixing Console
User’s Manual
INTRODUCTION 2
MX1204 FEATURES 2
BEFORE YOU BEGIN 2
USING THIS MANUAL 2
ABOUT THE MX1204 BLOCK DIAGRAM 2
MONO INPUT CHANNELS (1 -4) 3-4
STEREO INPUTS (5/6 –7/8) 3,5
MAIN MIX AND ALT 3/4 CONTROLS 3,8
INPUT / OUTPUT CONNECTIONS 3,9
MX1204 BLOCK DIAGRAM 6-7
REAR PANEL CONNECTIONS AND SWITCHES 10
SPECIFICATIONS 11

INTRODUCTION
The Podium Pro Audio MX1204 audio mixing console brings premium quality
audio processing circuitry into the compact desktop class of mixers. Carefully
designed signal routing, phantom microphone power, fully balanced design and
versatile effects loops allow this console to provide un-matched performance
and flexibility. Used in accordance with the information provided in this manual,
this product will give years of trouble free use.
MX1204 FEATURES
Four studio grade “Invisible” ultra low noise microphone (MIC)
Preamps
Four balanced line inputs
Direct-coupled signal processing.
Internal “switch-mode” power supply allows operation on 100 to
240VAC
Rugged steel construction provides superior noise shielding.
BEFORE YOU BEGIN
Read and follow these instructions.
Heed all warnings.
Do not use where the mixer may get wet.
Do not obstruct airflow through the ventilation slots.
Never defeat the AC polarizing or safety ground on the AC cord.
Be certain all equipment is OFF before making or breaking
connections.
Clean console only with a damp (not wet) cloth.
Refer all service needs to qualified personnel. There are no user
serviceable components inside.
USING THIS MANUAL
Having a basic understanding of what a mixing console does is very important. This
manual breaks the console down into basic function “blocks”. Details of all controls and
connections are provided for each block.
ABOUT THE MX1204 BLOCK DIAGRAM
To get the most out of your MX1204 mixer, you will need a thorough understanding of
what the console is doing. To help you, a block diagram of the circuitry has been
provided on pages 6 and 7. A block diagram is a simplified schematic which illustrates
signal flow from input to output and shows the numerous routing variations possible.
Throughout this manual, you will frequently see the opamp symbol. . .
h
This indicates that the current topic may be better understood by reviewing the block
diagram.
2
SPECIFICATIONS
MICROPHONE INPUTS: Balanced XLR. PIN 1: ground, PIN 2: (+), PIN 3: (-)
Frequency Response: (+0dB/-1dB) <20Hz to 40kHz
(+0dB/-3dB) <20Hz to 100kHz
Gain: Adjustable, +10dB to +60dB
Maximum Input Level: (gain set to +10dB) +12dBu
Input Impedance: ≈2.6kΩ (balanced)
Signal-to-Noise ratio: (Re. 0dBu in @ +22dB gain) 110dB (112dB A-weighted)
Equivalent Input Noise: (20Hz to 20kHz)
Source impedance = 0Ω: -134dB (135.7dB A-weighted)
Source impedance = 50Ω: -131dB (133.3dB A-weighted)
Source impedance = 150Ω: -129dB (130.5dB A-weighted)
Distortion: (THD+N) 0.005%/0.004% A-weighted
MONO LINE INPUTS: Balanced ¼” phone jack. TIP: (+), RING: (-), SLEEVE: ground
Frequency Response: (+0dB/-1dB) <10Hz to 90kHz
(+0dB/-3dB) <10Hz to 160kHz
Input impedance: ≈20kΩ (balanced), ≈10kΩ (unbalanced)
Gain Range: -10dB +40dB
Maximum Input Level: +30dBu
Channel-to-Channel Crosstalk: Main faders closed: -90dB, reference level 0dBu
Channel faders closed: -89dB, reference level 0dBu
Channels muted: -89.5dB, reference level 0dBu
1kHz sine wave applied, measurement band pass 20Hz–20kHz.
STEREO INPUTS: Balanced ¼” phone jacks. TIP: (+), RING: (-), SLEEVE: ground
Input impedance: ≈20kΩ (balanced)
Maximum input level: +22dBu
ALL EQUALIZERS
LOW: ± 15dB @ 80Hz, shelving, MID: ± 15dB @ 2.5kHz, HI: ± 15dB @ 12kHz, shelving
AUX SENDS: Unbalanced ¼” phone jacks. TIP: (+), SLEEVE: ground
Output impedance: ≈120Ω
Maximum output level: +22dBu
STEREO AUX RETURNS: Balanced ¼” phone jacks. TIP: (+), RING: (-), SLEEVE: ground
Input impedance: 20kΩ (balanced)
Maximum input level: +22dBu
MAIN OUTPUTS: Balanced XLR, PIN 1: ground, PIN 2: (+), PIN 3: (-)
Output impedance: ≈240Ω (balanced) ≈120Ω (unbalanced)
Nominal output level: +4dBu. Maximum output level: +28dBu
CONTROL ROOM OUTPUTS: Unbalanced ¼” phone jacks. TIP: (+), SLEEVE: ground
Output impedance: ≈120Ω (unbalanced)
Maximum output level: +22dBu
HEADPHONES OUTPUT: Unbalanced ¼” phone jack. TIP: Left, RING: Right, SLEEVE: ground
Output impedance: ≈120Ω (unbalanced)
Maximum output level: +19dBu into 150Ω (+25dBm)
MAIN MIX SYSTEM NOISE:
Main mix @ ∞, channel fader @ ∞: -105dB/-108dB (A-weighted) reference level +6dBu
Main mix @ ∞, channel fader @ 0 dB: -95dB/-97dB (A-weighted) reference level +6dBu
Main mix @ 0 dB, channel fader @ 0 dB: -82.5dB/-85dB (A-weighted) reference level +6dBu
Measured at MAIN OUT. Measurement band pass 20Hz –20kHz. Channels 1-4 @ unitygain, all EQs
flat, all channels on MAIN MIX. Channels 1/3 balance full CCW. Channels 2/4 balance full CW.
POWER CONSUMPTION: 100-240VAC, 40W, Fuse: T1.6AH
DIMENSIONS: H=97mm (3-7/8”) W=247mm (9-11/16”) D=328mm (13”). 2.56kg (5-5/8 lbs)
11

REAR PANEL CONNECTIONS AND SWITCHES
①AC FUSE
1 Amp AC fuse located underpanel on AC cord connector.
②AC CORD CONNECTOR
Standard IEC 3-wire power cord receptacle.
③A/C POWER ON/OFF SWITCH
④MICROPHONE PHANTOM POWER ON/OFF SWITCH
INSTALLATION
The MX1204 is designed for indoor use. Never use in a location where the unit may get
wet.
NEVER defeat the safety ground provision of the IEC power cord.
The console has ventilation slots on the sides of the enclosure. Do not install the console
in such a way as to block airflow through the unit.
CONNECTOR WIRING
You will need many cables to complete the installation. Many more will be required for signal
patching during sessions. Pre-fabricated cables may not always fit your needs and sometimes
onsite repairs are necessary. The following illustrations show the correct connector wiring.
10
MONO MIC/LINE INPUT CHANNELS (1 - 4) DETAILS ON PAGE 4
There are four identical MONO input channels located on
the left of the console. These channels are organized
vertically. At the top is an XLR microphone (MIC) input
jack. 48V “phantom” power is available for condenser
MICs. Next is a ¼” Tip Ring Sleeve (TRS) line level (LINE)
input jack. Each MONO channel can be used as either a
MIC or LINE input. The other controls provide a wide
variety sound shaping and gain adjustments as well as
signal routing and external processing.
STEREO INPUTS (5/6 - 7/8) DETAILS ON PAGE 5
There are two STEREO inputs (4 mono channels). These
channels are organized just like the MONO MIC/LINE
channels and have the same controls and capabilities.
However, no MIC inputs are provided. The line level
inputs are balanced ¼” TRS jacks.
MAIN MIX AND ALT 3/4 CONTROLS DETAILS ON PAGE 8
After all sources have been selected, equalization set and
effects loops created, all sources are summed onto the
LEFT/RIGHT MAIN BUS and the ALT 3/4 BUS are used
to control the overall level of the “mix”. There are
numerous routing options from this point forward. Here,
you will find the controls for the MAIN MIX level, ALT 3/4
level, AUX send and return, control room and
headphones.
INPUT / OUTPUT CONNECTIONS DETAILS ON PAGE 9
Here you will find all remaining input and output
connections. This is where the MX1204 interfaces with the
rest of the studio.
3

MONO MIC / LINE INPUT CONNECTIONS AND CONTROLS
①MIC INPUTS (1 - 4)
Balanced XLR microphone input jack.
PIN 1: ground, PIN 2: (+) signal, PIN 3: (-) signal
Phantom +48VDC supply: PINS 2 and 3 (when activated)
Ribbon, condenser and dynamic microphones are accommodated.
②LINE INPUTS (1 - 4)
Balanced ¼” phone jack (TRS). Line level input
TIP: (+) signal, RING: (-) signal, SLEEVE: ground
Any line level source (balanced or unbalanced) can be inserted here.
③LOW CUT PUSHBUTTON
When on, reduces low frequency sounds such as air conditioning, traffic and MIC
stand vibrations. Specifications: -3dB @ 75Hz, 18dB/octave rolloff.
④GAIN
Rotary MICrophone or LINE input sensitivity control. Use to set the level of this
channel relative to other inputs. Thus creating the desired “mix”. Do not use as a
fader.
⑤HI EQ
Adjusts high frequencies up or down. Set to 0 (center detent) for no EQ.
⑥MID EQ
Adjusts mid frequencies up or down. Set to 0 (center detent) for no EQ.
⑦LOW EQ
Adjusts low frequencies up or down. Set to 0 (center detent) for no EQ.
⑧MON PRE 
Adjusts the signal level sent to the AUX 1 bus.“MON PRE”is before, or pre
FADER. This means FADER adjustments will not change the signal level being
sent to the AUX 1 bus.
⑨FX POST 
FX is shorthand for Effects (reverb, echo, EQ). If you wish to route the signal
through an external device (effect) you would normally route it to the AUX 2 bus.
This control adjusts the signal level sent to the AUX 2 bus. “FX POST”is after, or
post FADER. This means FADER adjustments will change the signal level being
sent to the AUX 2 bus, allowing the level of the external effect to “follow” the
FADER.
⑩PAN
Adjusts the relative position of the sound across the “stage” (left/center/right).
⑪MUTE ALT 3/4 PUSHBUTTON 
The channel output normally goes to the LEFT/RIGHT bus. When “MUTE ALT 3/4“
is depressed the signal is re-directed to the ALT 3 & 4 bus, which has the effect of
muting the main output and making it available for headphone monitoring.
⑫MUTE LED
This yellow LED lights whenever the MUTE ALT 3/4 ⑪is depressed.
⑬PEAK LED
This red LED lights when the input signal is too high. Lower input GAIN ④or
source level when this occurs.
⑭FADER
Use only to “fade” the channel in or out during the performance. This is not a volume control.
4
INPUT / OUTPUT CONNECTIONS
ⒶAUX 1 SEND
Unbalanced ¼” phone jack, Tip
Sleeve (TS). The sum of all signals
sent to the AUX 1 bus are output
here. NOTE: All feeds to the AUX 1
bus are pre-fader, also known as
“dry”.
ⒷAUX 2 SEND
Unbalanced ¼” phone jack (TS).
The sum of all signals sent to the
AUX 2 bus are output here. NOTE:
All feeds to the AUX 2 bus are post-
fader, also known as “wet”.
ⒸSTEREO AUX 1 RETURN 
Balanced ¼” phone jack (TRS). The STEREO AUX 1 RETURN is sent to the
LEFT/RIGHT bus. If only the LEFT input jack is used the signal is sent to both the LEFT
and RIGHT channels. (MONO)
ⒹSTEREO AUX 2 RETURN 
Balanced ¼” phone jack (TRS). The STEREO AUX 2 RETURN can be sent to either the
LEFT/RIGHT bus or the ALT 3 –4 bus. If only the LEFT input jack is used the signal is
sent to both the LEFT and RIGHT (MONO).
ⒺALT 3 –4 OUTPUTS
Unbalanced ¼” phone jack (TS). All signals sent to the ALT 3 –4 bus (with the MUTE
switches) are combined and sent to these output connectors.
ⒻCONTROL ROOM OUTPUTS L and R
Unbalanced ¼” phone jack (TS). Normally used to provide line level signal to the
monitor speakers in the control room.
ⒼTAPE INPUT
Unbalanced phono jacks (RCA). Normally used for a 2-track recording device input.
“TAPE INPUT” can also be used as an additional stereo line level input. For example,
additional sound elements can be added to the mix from a CD player, iPod, MP3 player
or computer.
ⒽTAPE OUTPUT
Unbalanced phono jacks (RCA). Wired in parallel with the MAIN OUTPUTS Ⓙ.
Normally connected to the inputs of a 2-track recording device.
ⒾPHONES
Unbalanced ¼” phone jack (stereo TRS). You can connect monitoring headphones
here. This output is the same signal as the CONTROL ROOM Ⓕoutput.
ⒿMAIN OUTPUTS
Balanced XLR jacks. The LEFT and RIGHT “MAIN MIX”signals are available here.
9

MAIN MIX AND ALT 3/4 CONTROLS
①MAIN MIX FADERS
These faders control the LEFT and RIGHT MAIN MIX output levels.
(See “ⒿMAIN OUTPUTS”on page 9) Use these faders like a
system volume control.
②ALT 3-4 FADERS
These faders control the ALT 3 and ALT 4 output levels. The left
fader controls ALT 3. The right fader controls ALT 4.
③AUX 1 SEND MON 
Adjusts the output level of AUX 1 SEND output only. Typically used
to control the stage monitor speakers.
④AUX 2 SEND FX 
Adjusts the output level of AUX 2 SEND only. Typically used to
control the signal level sent to external processor(s).
⑤STEREO AUX 1 RETURN 
Adjusts the level of the incoming signal, which is mixed with the
LEFT/RIGHT bus.
⑥STEREO AUX 1 RETURN MON PRE
The STEREO AUX 1 RETURN signal is summed to mono, pre-
fader and sent to the AUX 1 bus. This allows the application of
effects to the stage monitors.
⑦STEREO AUX 2 RETURN
Adjusts the level of the STEREO AUX 2 RETURN signal.
⑧MAIN MIX / ALT 3 - 4
This push button assigns the STEREO AUX2 RETURN either to
the LEFT/RIGHT bus (MAIN MIX) or to the ALT 3 - 4 bus.
⑨MAIN MIX PUSHBUTTON
When depressed, assigns the stereo MAIN MIX signal to the control room (CTRL R) and
headphone (PHONES) outputs.
⑩ALT 3 –4 PUSHBUTTON
When depressed, assigns the ALT 3 –4 bus signal to the control room (CTRL R) and headphone
(PHONES) outputs.
⑪TAPE PUSHBUTTON
When depressed, assigns the LEFT and RIGHT TAPE input signals to the control room (CTRL R)
and headphone (PHONES) outputs.
⑫CTRL R & PHONES
Adjusts the level of the signal sent to the control room and headphone outputs.
⑬TAPE TO MAIN PUSHBUTTON
Press to send the TAPE input directly to the LEFT/RIGHT bus (MAIN MIX). Typically used for
playback monitoring or adding pre-recorded elements to the mix..
⑭LED VU METER
These LEDs indicate the signal level of the MAIN MIX. For best results, avoid operation above
0dB. Occasional flashing of the +5dB or even the +10dB may be allowable but operation with the
CLIP LEDs flashing must be avoided.
⑮+48V LED
Condenser microphones require an external power supply to operate. This blue LED lights
whenever the 48-volt microphone phantom power is on. The on/off switch for the phantom supply
is located on the rear panel of the console.
When the phantom supply is on, +48V is sent to all four of the microphone connectors.
You may use either dynamic or condenser microphones while the “phantom” power is
on.
Never use a balanced to unbalanced adapter when the phantom power is on!
⑯POWER LED
This red LED lights whenever the console is on. The AC power switch is located on the rear panel
of the console. 8
STEREO INPUT CONNECTIONS AND CONTROLS
①MONO L
Balanced ¼” phone jack (TRS). LEFT or MONO line level input. NOTE:
When only the MONO “L”input jack is used, the signal is sent to both left
and right channels (MONO).
①R
Balanced ¼” phone jack (TRS). RIGHT line level input.
②LEVEL
Use this pushbutton switch to set the circuit gain to either +4dB (OUT) or
-10dB (IN).
③HI EQ
Adjusts high frequencies up or down. Set to 0 (center detent) for no EQ.
④MID EQ
Adjusts mid frequencies up or down. Set to 0 (center detent) for no EQ.
⑤LOW EQ
Adjusts low frequencies up or down. Set to 0 (center detent) for no EQ.
⑥MON PRE 
Adjusts the signal level sent to the AUX 1 bus. “MON PRE” is before, or
pre FADER. This means FADER adjustments will not change the signal
level being sent to the AUX 1 bus.
⑦FX POST 
FX is shorthand for Effects (reverb, echo, EQ). If you wish to route the
signal through an external device (effect) you would normally route it to
the AUX 2 bus. This control adjusts the signal level sent to the AUX 2
bus. “FX POST” is after, or post FADER. This means FADER adjustments
will change the signal level being sent to the AUX 2 bus, allowing the
level of the external effect to “follow” the FADER.
⑧BAL
Adjusts the relative signal level (BALANCE) sent to the LEFT/RIGHT
bus.
⑨5/6 MUTE ALT 3/4 PUSHBUTTON 
The channel output normally goes to the LEFT/RIGHT bus. When “5/6
MUTE ALT 3/4“ is depressed the signal is re-directed to the ALT 3 & 4
bus, which has the effect of muting the main output and making it
available for headphone monitoring.
MUTE LED
This yellow LED lights whenever the 5/6 MUTE ALT 3/4 ⑨is depressed.
⑪PEAK LED
This red LED lights when the input signal is too high. Lower source level when this
occurs.
⑫FADER
Use only to “fade” the channel in or out during the performance. This is not a volume control.
5

Podium Pro Audio MX1204 BLOCK DIAGRAM
6 7