SQN Electronics Ltd
SQN-3M Miniature 4:1 ENG Audio Mixer
|The original broadcast quality mono portable mixer for TV, film and radio locations|
|Click on picture
|Starting with serial number 34000, the
circuitry was revised using elements from our SQN-4S to make the
SQN-3M Series 3000vII.
The important facilities added were
|The SQN-3 Type M four
input miniature audio mixer was designed to provide all the basic
functions found necessary in using professional microphones for
location recording. Since its introduction in 1980 it has been
adopted as the industry standard for mono work in most European
countries and further afield and has established a solid reputation
for quality, reliability and longevity.
|Click on picture
|It remains the smallest truly professional mixer
today offering comprehensive microphone powering, peak metering, a
peak limiter and off tape monitoring.
|Powered by 6 AA size internal alkaline cells, the
SQN-3 Type M commonly functions for a week or two in professional
use without reloading. Its unique sophisticated power supply
delivers 48V phantom power until the battery dies, and the quick
change battery compartment permits reloading in a few seconds.
Provision is also made for accepting an unusually wide range (5V to
18V dc) of external supplies of either polarity without adjustment
and with good efficiency.
|Features and Specification - SQN-3 Type M
|Three identical channels using
industry standard XLR-3 type female connectors. Each channel is
individually switchable for:
|-70dBu for 0dB (peak level) on the meter with the channel gain
at maximum and the Master Gain at 0dB.
||-20dBu (0dBu with 20dB attenuation).
||The unit is normally shipped wired to IEC standards, i.e. pin 2
in phase and positive T powering.
||-129dBu (A weighted) with 200 Ohm source resistance.
|30Hz to 20kHz +0,-1dB
|Line Input 1
||Dedicated balanced input by way of fourth XLR-3 female
connector with side panel fader control.
2, 3, & 4
|The mic channels 1, 2 & 3 may also be switched from mic. to
line input mode, retaining their effective input attenuator and
Bass Cut controls.
|Aux. Monitor Input
||Balanced input carried on same 5-way D.I.N. connector as line
|Aux. Input Level
||Minimum level -19dB; maximum level +11dB.
||Recessed front panel rotary controls. Knobs contoured for ease
of adjustment allowing fader position to be judged by touch or
viewed from a distance.
||Front panel rotary control governing all 4 inputs and allowing
the level of mix to be adjusted from zero to +3dB (detent at
||Fast response peak reading meter with a log calibrated linear
scale; full wave rectification. Nordic
Norm and VU versions are available to special order. The meter
scale is permanently illuminated by light emitting diodes for low
||Switchable; operates on the metered output to give approx. 20:1
compression ratio over an 18dB range. Attack time 0.5ms. Release
|Line Up Tone
||1.1kHz tone operated by a front panel TONE / MIC switch. The
output level is internally adjustable and is usually set 8dB below
|Line Output 1
||Balanced, floating source with a clipping level of + 18dBu, or
+20.5dBu into 10k Ohms. The output level is preset so that 0dB
(peak level) on the meter corresponds to +8dBu. Distortion at
+15dBu is less than 0.1% over the range of 30Hz to 20kHz. The
output connector is a standard XLR-3 male type and the output
impedance is 160 Ohms.
|Line Output 2
||Derived from Line Output 1, a second balanced line output is
available from a 5-way D.I.N. locking connector which may be
switched to Mic. level (-50dBu) by a toggle switch set into the
mixer baseplate. Monitoring return on this socket facilitates
single cable connection to recorder.
||Unbalanced output at -40 dBu allows connection of ancillary equipment such as transcription recorder.|
||The phones output level is adjustable from zero to 1.5V by a
control on the side panel. The connector is a 6.3mm stereo jack,
normally wired with tip and ring joined, accepting Gauge A or B
||Monitoring is selected by the MXR / AUX switch on the front
panel. Choices are:
||Pre-Fade listening is available on CH3. The output of the CH3
Mic. amplifier may be monitored in the headphones even when the
fader is closed. This is selected by a third, biased position on
the MXR / AUX switch.
||The mixer now incorporates a slate or announcement mic with
automatic gain control. The mic is placed behind the front panel
between the TONE / MIC switch and the CH2 Fader. It is selected by
pressing the TONE / MIC switch to the right. The mic output
replaces the main audio. The switch is biased to return to the off
position when released. If the monitoring is switched to external,
it automatically returns to internal while the slate mic is
||Six AA (UM-3) size cells housed in a quick change compartment.
The acceptable range of battery voltages is 5V dc to 18V dc
allowing the use of Nickel-Cadmium rechargeable cells,
Alkaline-Manganese cells or even Lithium cells. Access is provided
to the battery terminals for recharging. A fresh set of
Alkaline-Manganese cells will power the unit for more than 12 hours
when using dynamic microphones.
||A supply in the range 5V dc to 18V dc may be used. The maximum
consumption will be 1.5W and quiescent consumption, without
microphones, 700mW. The power input terminals float with respect to
the SQN-3 ground so that external supplies of either polarity may
be used. Alternatively, a power supply which does not share a
ground with the SQN-3 may be used e.g. a camera battery.
||The meter is fitted with a suppressed-zero scale, brought into
operation by a front panel push button, which indicates the battery
||210mm x 120mm x 44mm.
||The outer case of the mixer is made
of aluminium. The end blocks holding the connectors are milled from
solid aluminium bar.
All control knobs are special to SQN and are turned and milled from solid aluminium bar. The internal battery compartment is milled and bored from a solid block of polyacetal engineering polymer and the moving parts are aluminium and stainless steel.
All labels and legends on the mixer are permanent. On the end blocks they are engraved; on the front panel they are printed into the hard-anodised surface; on the baseplate they are reverse printed on a polycarbonate label.
The mechanical construction is a development of a system which
has proven in the past to be resistant to mechanical
||1.37kg. (1.51kg with batteries).
||The working temperature range is -40ºC to
|The SQN-3M mixer offers the professional
|Download This Document in Adobe Acrobat format|
|©1999 & 2002 SQN Electronics Ltd|