Canford MINX MIXER User manual

02-406 (Issue 1) 01/03 MINX MIXER -OPERATING INSTRUCTIONS
MINX MIXER
OPERATING INSTRUCTIONS
Manufactured by Canford Audio plc
Under licence from Audio Systems Components Ltd
02-406 (Issue 1) 02/02
CANFORD AUDIO PLC
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TYNE & WEAR NE38 OBW, UK
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02-406 (Issue 1) 01/03 MINX MIXER -OPERATING INSTRUCTIONS
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CONTENTS
Introduction 3
Application Notes 3
Operating Instructions
Front Panel controls
-Input Level 4
-Pre-fade listed (PFL) 4
-High Pass Filter 4
-Headphone Monitoring 4
-Talkback Routing (PTT) 5
-Limiter 5
-Battery Check 5
-PPM 5
-Headphone level 5
-Oscillator 5
Back Panel
-Input Selector 6
-Control Line Input 6
-Mixer Output 6
-Output Attenuator 6
-Battery Switch 6
-IEC Mains Socket 6
-Fuse Holder 7
-Headphone sockets 7
-Battery Compartment 7
Phantom Power module 7
Phantom Power (obsolete version) 8
12Volt powering 8
Technical Specifications 9
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02-406 (Issue 1) 01/03 MINX MIXER -OPERATING INSTRUCTIONS
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INTRODUCTION
Thank you for choosing the Minx mini mixer.
A lot of care and attention has gone into the design and build of this product and we hope that it
will serve you well. Like any technology product the only way to get the best from it is to
thoroughly read and understand the manual.
Should you find any aspect of this product and its related documentation ambiguous or confusing
please let us know.
Additionally, should you perceive ways in which the Minx could be improved we would welcome
your comments.
APPLICATION
The Minx was designed to be for 2 man operation nominally presenter (DJ) and engineer. The
presenter need not necessarily be next to the engineer as talkback exists from engineer to
presenter also the engineer/presenter can talk back two-way with base on the CUE line.
Typical uses are:
Sports Events Mics for presenter, actuality and
guest.
Town Hall Expanding existing mic positions
at debates etc.
Live OBs Less than 6lb in weight and
battery powered the Minx can
feed radio links (remote pickup)
or radio mics at mic level.
These are just typical uses. The Minx is so compact and versatile, yet with such good quality
specs. it can be used as a sub-mixer at concerts, feed ENG cameras/VCRs or for local work.
CANFORD AUDIO PLC
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TYNE & WEAR NE38 OBW, UK
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02-406 (Issue 1) 01/03 MINX MIXER -OPERATING INSTRUCTIONS
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OPERATING
INSTRUCTIONS
FRONT PANEL CONTROLS
1. Input Level Control
A dual concentric pot. arrangement feeding the mix bus where the back (outer) knob
adjusts GAIN and the front (inner) knob acts as a FADER. Level set by the GAIN control
is progressively attenuated by the FADER control by adjusting FADER anti-clockwise
from the fully open (clockwise) position. The FADER control, therefore, does not
contribute any more gain i.e. does not have (say) 10dB in hand.
2. Pre-Fade Listen (PFL)
When selected, as indicated by orange iris, allows monitoring of this (and any other
channel currently in PFL mode) or engineer's (1 ENG.) headphones only. FADER
(see Section 1) is not operative and channels with PFL selected do not contribute to mix
bus or presenter's (2 PRES) headphones. Whenever PFL is selected for one or more
channels, the PPM meter automatically switches over to follow.
3. High Pass or Rumble Filter
When selected, as indicated by orange iris, imposes a 6dB per octave high pass
filter on the channel. Turnover point (-1dB) is 120 Hz, -3dB point is 80 Hz.
4. Headphone Monitoring Select Switches
Mounted above the PPM are presenter's (PRES) and engineer's (ENG.) locking toggle
switches for monitoring either mixer output (O/P) or control line input (CUE)
on their respective headphones. For engineer only, monitoring will be overridden by
PFL if selected.
5. Talkback Routing (PTT)
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02-406 (Issue 1) 01/03 MINX MIXER -OPERATING INSTRUCTIONS
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Associated with the electret talkback microphone (5a), this centre biased momentary
toggle switch directs the output of the talkback mic. amp either to the control line
(CUE) when pushed to the left (i.e. towards PRES monitor select toggle) or to the
mixer output (O/P) when pushed to the right. Thus the engineer can talk to the
presenter, even during a live programme, by selecting CUE on presenter's
headphones and holding the PTT toggle to the left.
6. Limiter
When selected, as indicated by orange iris, limits output at +8dBm (factory set).
Operation indicated by the led fitted into the PPM, attack and release program
controlled.
7. Battery Check (Batt Test)
Push to read battery condition on the PPM. Replace/recharge batteries when level
reads lower than 5 on the PPM scale. Scale reads between 6 -7 with new batteries.
8. Peak Program Meter (PPM)
Scale 4=0dBu, 6=+8dBu. Movement and electronics to BS4297.
9. Headphone Level (Cans)
A dual concentric pot. arrangement where the back (outer) knob adjusts presenter's (2
PRES) headphone level and the front (inner) knob adjusts engineer's (1ENG)
headphone level independently.
10. Oscillator (OSC)
Directly left of the headphone level controls is the oscillator on/off toggle
switch.When switched downwards (ON) the oscillator generates a 1KHz tone at
0dBu which is routed to the mixer output. This can prove useful in patching-in the
Minx at a radio station when it is being used at a remote location or to ‘slate’ tape.
The oscillator is also essential for setting correct level line-ups.
NOTE:
The oscillator circuit employed uses a thermistor which will initially overshoot before
settling back to 0dBu. If following equipment is sensitive to overshoot, turn LIMITER on
before using oscillator.
CANFORD AUDIO PLC
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TYNE & WEAR NE38 OBW, UK
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OPERATING INSTRUCTIONS
BACK PANEL
11. Input Selector (Mic/Line)
When pushed-in, as indicated by orange iris, pads input to accept line level signals.
12. Control Line Input (Cue)
Accepts line level signals for monitoring by presenter or engineer's headphones
(see 4). Connection may be by 3 pin XLR type connector or bare wires as in
temporary 'phone circuits.
13. Mixer Output (Output)
Normally line level output (but see 14) XLR connector has low source impedance
for driving good quality music circuits, bare wire terminals have 600 ohm source
impedance for (e.g.) temporary 'phone circuits.
14. Output Attenuator (-50dbm)
Makes mixer output mic. level and changes source impedance to 200 ohms
(typical mic. impedance).
15. Battery Switch (On Off/Charge)
Locking toggle switch. In the ON (up) position switches the mixer on under battery
power, in the OFF/CHARGE position switches mixer off under battery power but
enables Ni-Cad charging circuits (see 16).
16. IEC Mains Socket/Integral Fuse Holder
Regardless of battery switch position (see 15) application of mains power via this
socket (110v or 240v 60/50 Hz MUST be specified) always powers the mixer. With
reference to 15 above, if ON position selected and mains power is lost the mixer will
fail to battery operation. If OFF/CHARGE position selected the mixer is mains
powered and the Ni-Cads are being charged.
DO NOT OPERATE THE MINX FROM MAINS POWER WITH ORDINARY DRY CELLS AND
OFF/CHARGE POSITION SELECTED.
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17. Fuse Holder
A pull out drawer beneath the mains plug entry contains the 250mA, 20mm fuse and a
spare.
18. Headphones (Cans) (1 ENG. 2 PRES)
Jack sockets for engineer and presenter's headphones.
Models AP and AT use 'A' gauge tip/ring/sleeve 6.4 mm stereo jack. Models BP and BT
use 'B' gauge tip/ring/sleeve 6.4 mm stereo jack having the small tip.
19. Battery Compartment
Underneath the Minx you will find the battery compartment.
Here there is room for 2 x PP3 batteries and the phantom power module. If the
phantom power module is not fitted, there is space for two spare PP3 batteries.
(Take care to insulate battery connectors on spares.)
Phantom Power Module
48 volt Phantom Power option -models AP (93-931) and BP (93-938)
The 48 volt Phantom Power Supply is applied to all of the microphone inputs.
The Phantom Power facility is controlled by a 3 position switch on the Phantom Module PCB,
contained in the battery compartment of the mixer.
There is a label on the battery compartment lid, which indicates the switch settings.
The switch positions are: Phantom Power Batt
Disable
Regular Batt/Mains
Phantom Power Batt
The Phantom Power is generated from the single PP3 battery next to the Phantom
Module PCB. Use of phantom power does not then affect the life of the regular pair of
batteries but current is always drawn from the separate Phantom Power Battery, even on
mains operation. When the On-Off/Charge switch is in the Off position, there is no drain
from the Phantom Power Battery. There is no provision for charging the Phantom Power
Battery on mains operation, and no requirement to remove this battery on mains
operation in the Off/Charge position.
Disable
The Phantom supply is disabled. No current is drawn from the Phantom Power Battery
and no extra current is drawn from the regular pair of batteries under any operating
conditions.
Regular Batt/Mains
The Phantom Power is generated from the Mains Supply, or the regular pair of batteries
if the mains is removed. The life of one the regular PP3 batteries is reduced; in the worst
case this reduction is to approximately half of the battery life with an independent
Phantom Power Battery.
Whichever battery is being used for Phantom Power, there is always some current drain due to
the Phantom Power supply, unless Off/Charge is selected and/or Phantom Disable is selected.
The drain on this battery then depends on the number and type of microphones in use.
CANFORD AUDIO PLC
CROWTHER ROAD WASHINGTON
TYNE & WEAR NE38 OBW, UK
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02-406 (Issue 1) 01/03 MINX MIXER -OPERATING INSTRUCTIONS
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Phantom Power (obsolete version using 22.5 volt camera batteries)
Derived from 2 x B122 22.5 Volt batteries only, they are housed in the battery compartment.
Consumption is approximately 2 -3mA per microphone being powered. Approximate battery life
is 8 hours.
NOTE: The Minx has no provision for recharging the Phantom power batteries, once expired they
must be replaced. Batteries must be fitted if phantom power is required when using the Minx on
AC.
If the Minx is not being used ensure that Phantom power mics are either unplugged from the
mixer or the Mic/Line switch is set to LINE.
When using Dynamic mics ensure that both B122 batteries are removed from the battery
compartment.
B122 batteries are no longer available.
Addition of the Phantom Power Module to existing Minx Mixers is a chargeable factory retrofit.
12 Volt Powering –Optional –Models AT and BT
Derived from PP3 batteries or AC supply, connected to microphone when locking toggle switches
are selected in DOWN position.
NOTE:
If Mic/Line switch is in line position ensure that corresponding ‘T’ Power toggle switch is in the
‘OFF’ (up) position. When using Dynamic microphones ensure that corresponding ‘T’ power
toggle switch is in the ‘OFF’ position otherwise damage to the microphone may result.
WARNING:
Do not use 12 Volt ‘T’ Powering with 48 Volt Phantom power microphones or Dynamic mics.
Do not use 48 Volt Phantom powering with 12 Volt ‘T’ Power microphones or Dynamic
microphones.
CANFORD AUDIO PLC
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TYNE & WEAR NE38 OBW, UK
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02-406 (Issue 1) 01/03 MINX MIXER -OPERATING INSTRUCTIONS
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TECHNICAL SPECIFICATION
Input
Noise Referred to Input
Measurement Method Mic Line Output Noise
22Hz to 22KHz RMS -121.1dB -79.7dB -75.0dB
A weighted RMS -124.7dB -82.3dB -78.1dB
CCIR weighted RMS -117.9dB -73.4dB -69.0dB
CCIR weighted quasi peak -112.1dB -69.3dB -65.1dB
CCIR/ARM ref 2kHz -122.8dB -80.0dB -75.7dB
Harmonic Distortion <0.1% at 1KHz
Impedance Mic > 1K ohm floating
(Both transfer bal.) Line > 10K ohm bridging
Sensitivity -70dBm to -40dBm (Mic)
(Fader fully open) -20dBm to + 10dBm (Line)
Headroom at Inputs Mic better than 30dB
(Fader fully open) Line better than 20dB
Amplitude-frequency response
(w.r.t. 1KHz) 40Hz –15KHz ±1.0dB
125Hz –10KHz ±0.5dB
Hi-pass filter -3dB at 80Hz Slope = 6dB/octave
Wiring Conventions
XLR -Type connectors: Pin 1 = Ground
Pin 2 =+ve Phase or ‘Hot’
Pin 3 = -ve Phase or ‘Cold’
RCA Phono connectors: Tip = +ve Phase or ‘Hot’
Ring = -ve Phase or ‘Cold’
1/4” Jacks connectors Tip = +ve Phase or ‘Hot’
Ring = -ve Phase or ‘Cold’
Sleeve = Ground
Bare wire terminals: Red = +ve Phase or ‘Hot’
Black = -ve Phase or ‘Cold’
CANFORD AUDIO PLC
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TYNE & WEAR NE38 OBW, UK
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