| Sensitivity |
-78dBu for nominal line level (PPM4, 0VU)
with the channel gain at maximum and the master
gain at 0dB |
| Max
Level, Mic Inputs |
-20dBu (+4dBu with full attenuation)
|
| Noise
Figure |
-130dBu (A weighted) from a 200 Ohm source. |
| Frequency
Response |
20Hz to 20kHz +0, -1dB, referred to 1kHz. |
| Crosstalk |
Isolation, channel to unrelated channel: 75dB
at 1kHz, 60dB at 15kHz. |
| Channel
Configuration |
The mixer has five input channels, all
of which have the same input selectors, bass
cuts and attenuators. The routing arrangements
for CH1 & 2 differ from those for CH3,
4 & 5.
|
Channels
1 & 2
[GANG 1-2] |
The operation of the CH1, CH2 pair is controlled
by the GANG 1-2 switch on the front panel.
This switch has three positions:
- Twin MONO [O] in which the channels are
unganged and each input channel can be routed
to either or both of the output channels.
- Stereo [S] ganging in which the Channel
1 fader controls the gain of both channels
and a stereo balance control on the side
panel comes into play.
- Mid-Side [MAT] ganging in which the Channel
1 fader controls the gain of both channels
and the Channel 2 fader acts as an image
width control. The incoming signal is assumed
to be in MS format and is matrixed to AB.
The stereo balance control remains active
and will balance the matrixed signal.
|
| Phase
Switch |
A front panel switch inverts CH2 phase. This
also interchanges left and right in an MS encoded
signal. |
| Channel
3 |
CH3 can be routed to LEFT, RIGHT or to a PANpot. |
| Channels
4 & 5 |
Each of CH4 and CH5 can be routed to LEFT,
RIGHT or CENTRE (both). |
| Monitor
Return Input |
Balanced inputs with a range of sensitivity
from -20dBu to +20dBu for loudness parity with
the internal monitoring. The sensitivity is adjusted
by a screwdriver preset on the base, with an
internal range switch. |
Mixing Bus Inputs
|
Two inputs directly into the summing amplifiers with their gain adjustable inside
the mixer. Maximum sensitivity is 0dBu for +8dBu at the balanced outputs with
the master gain set at 0.
|
| Balanced
Outputs |
Two electronically balanced line drivers. The
outputs are available on individual XLR connectors
and a combined Multi-way connector.
|
| Output
Attenuators |
Switches on the base allow attenuation by
50dB at either set of connectors for microphone
level feed. |
| Line
Drivers |
Electronically balanced sources. Clipping level is +20dBm into 600 Ohms. Distortion
at the nominal peak level of +8dBm is less than 0.01% with a 600 Ohm load 20Hz
to 20kHz. The output resistance is below 10 Ohms. It is permissible to forcibly
unbalance the outputs to drive unbalanced loads. The balanced Mic-Level sends
are derived from attenuator pads across the main outputs. Their source impedance
of 200 Ohms is essentially resistive. |
| Unbalanced
Outputs |
A SUBSIDIARY I/O connector carries separately buffered
outputs at 6dB below the main outputs. |
Post-Fader
Outputs,
All Channels |
The SUBSIDIARY I/O connector carries buffered
outputs at a nominal level of -12dBu from a 10k
Ohm source resistance. If an external link is
made on the connector, CH4 and CH5 are removed
from the mix and the operation of the signal
routing for CH3 is changed. Selecting PAN for
CH3 will now switch the channel out of the mix
instead of to the PANpot. This arrangement allows
the five channels to be extracted separately. |
Meters
|
Twin peak reading, logarithmic level meters
with Peak Programme Meter (PPM) dynamics. Scaling
may be BBC PPM, Nordic
Norm, or SMPTE.
VU meters can also be provided. The meters are normally calibrated with the
mixer driving a bridging load of 10k Ohms. While the mixer is operating the meters
are illuminated by low power light emitting diodes. |
| Line
Output Level |
The nominal line level is normally set at 0dBu for PPM metered mixers and +4dBu
for VU metered mixers. Peak level, which is used as a reference for the limiters,
is considered to be 8dB above this setting. Other calibration levels are readily
available to order. |
| Output
Limiters |
[O]ff [M]ono [S]tereo (ganged) Attack time
constant 0.5ms, release time 100ms. The limiter
range is 20dB. An LED for each output channel
indicates limiter action. This Graph shows
the entry into limiting on a steady signal for
a nominal peak level of 8dBu |
| Line-up
Tone |
The Line-up tone is a sine wave at 1kHz with
distortion below 0.1% which is inserted into
both channels, displacing the audio output. When
the [GANG 1-2] switch is in either of the ganged
positions, the left hand channel tone is interrupted
for 250ms every 3s. The tone switch on the front
panel is a three position toggle, shared with
the Slating Microphone. |
| Monitoring |
The mixer has a pair of headphone amplifiers
with adjustable gain. These are capable of
driving most types of headphone to a suitable
level. Pre-Fade listening to four of the input
channels is possible as is MS matrixing of
the two output channels so that an MS recording
may be monitored in the equivalent AB stereo.
The headphone gain control is the tall
knurled knob easily accessible on the left side panel.
|
| Monitoring
Mode Selector |
The monitoring mode rotary selector switch
on the front panel [PHONES] has the following
functions.
- S Stereo
- R Right Channel
- L Left Channel
- MS MS Matrix (MS heard as AB stereo)
- L-R Left minus Right (MS stereo equivalent
Right)
- L+R Left plus Right
(MS stereo equivalent Left or Phase Check)
|
| Monitoring
Source Selector |
A front panel toggle switch selects the monitoring source as either internal
[MXR] or external [AUX]
|
| Pre-Fade
Listen |
A pair of front panel toggle switches selects Pre-Fade Listen for channels 2
or 3 and 4 or 5. The switches are three position, centre off.
|
| Slating
Microphone |
A microphone is mounted behind the front panel near the centre of the mixer.
When in use, the output of the microphone is levelled by a compressor and displaces
the normal audio, appearing on the mixer outputs and in the monitoring system.
While the microphone is active, the monitoring mode automatically reverts to
the internal or [MXR] setting. The Slating Microphone switch on the front panel
is a three position toggle, shared with the Line-up tone.
|
| Batteries |
Eight AA size cells housed in a quick-change compartment. The acceptable range
of voltages is 6 to 24 Vdc allowing the use of most cell technologies.
|
| Battery
Drain |
130mA at 12 Vdc with unpowered mics. Battery
life with alkaline cells will be about 10 hours.
|
| Battery
Test |
The right channel meter is fitted with a suppressed-zero
battery voltage scale, brought into operation
by a front panel push button. |
External
Power |
A supply in the range 6 to 24 Vdc may be used.
The maximum consumption will be 2.5W and quiescent
consumption, without microphones, 1.6W. The input
terminals float with respect to ground. Either
(or neither) side may be grounded at will, thereby
allowing the use of floating supplies or grounded
supplies of either polarity. There will be no
possibility of hum-loops being formed.
|
| Power
Distribution |
The mixer carries two four-way connectors,
one of which [DC] gives access to the internal
batteries for charging and also serves to connect
to an external power source. The second connector
[PT] is an output which provides a switched,
short circuit proof connection to the power supplied
to [DC]. This allows the mixer to be used as
the focal point for a system of interconnected
devices, all controlled from the mixer’s
power switch. |
| Temperature
Range |
The mixer is designed to work over the temperature
range of -20 to +60 °C.
|
| Dimensions |
The dimensions of the mixer case are: Height
47mm, Width 297mm, Depth 161mm
|
| Construction |
The outer case of the mixer is made of
aluminium. The end blocks holding the connectors
and the panpots are milled from solid aluminium
bar. Inside the mixer is an inner compartment
of steel, tin-plated after forming, which contains
all of the circuitry that might be sensitive
to radio frequency interference. The top and
bottom of this compartment are sealed by copper
screens and rf gasket material and all inputs
to and outputs from this compartment are filtered.
The circuitry is constructed on multi-layer
printed circuit boards with internal ground
and power planes which ensure the integrity
of the internal grounding system.
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 plastics material 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 damage.
|
| Weight |
The weight of the mixer without batteries
is 2.1kg
|
The SQN-5S mixer offers the professional recordist:
|
| |
- Unsurpassed sound quality
- Industry standard acceptability
- User friendly ergonomic layout
- Tried and tested electronic design
- Superior mechanical engineering
|
- Lowest running costs
- Highest resale value
- Long trouble-free service
- The utmost in portability
- Efficient factory back-up service
|
|
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