spl Mk3 Channel Strip Instruction Manual
- June 14, 2024
- spl
Table of Contents
spl Mk3 Channel Strip
Getting started
Read the safety instructions starting on page 14.
Make sure that the mains voltage of the Channel One Mk3 corresponds to the
voltage of your region and that the fuse has the correct value for the
selected voltage (see specifications on page 12).
The power switch on the back of the Channel One Mk3 must be in the off
position.
(Off = O / On = I).
Connect the supplied power cord to the power connector of the Channel One Mk3
and to a power outlet.
If the supplied power cord does not match your mains socket outlet, please
contact your dealer.
The devices that are to be connected to the Channel One Mk3 must be be
switched off.
Connect your devices with appropriate audio cables (XLR) to the inputs and
outputs of the Channel One Mk 3.
Audio cables not included in the scope of delivery.
Power on
Switch on the power switch on the rear panel of the Channel One Mk3 (On = I).
The PWR LED and all activated switches light up.
Activating phantom power
Please always follow these instructions to active and deactivate phantom power
– also when changing microphones. The input stage of the Channel One Mk3 can
be damaged if you ignore these procedures.
- Connect the microphone to the Channel One Mk 3.
- Now activate Phantom Power to use the microphone.
- When recording is completed, first thing is to deactivate the phantom power.
- Wait at least one minute after deactivation of phantom power before disconnecting the microphone! This ensures residual current will be discharged.
Power off
Switch off the power switch on the rear panel of the Channel One Mk 3 (Off =
O).
The PWR LED and all activated switches no longer light up.
Discrete Preamplifier
Channel One Mk3 is equipped with one discrete preamplifier.
Mic A, Mic B, Line/Inst
This switch is used to select the input source.
Mic In A & Mic In B
Microphones of all types can be connected to the Mic input (dynamic,
condenser, tube and ribbon). Channel One Mk3 offers two microphone inputs on
the rear – for Mic A and Mic B. Two microphones can be connected here.
Instrument
The instrument input is the only input on the front panel for easy access at
any time. It is designed for the connection of high-impedance (higher than 1
kΩ) instruments.
IMPORTANT: As long as the instrument input is in use, the line input on
the rear panel is deactivated.
Line In
Low impedance line signals (less than 1 kΩ) should be connected to the rear
panel Line In input.
GND Lift
The GND switch can be used to eliminate ground loops by disconnecting the
internal ground from the housing ground when the switch is pressed.
Gain
The gain control can be t the preamplification.
For microphone signals, a preamplification of up to 68 dB can be realized.
When optionally equipped with an input transformer, approximately +14 dB must
be added to the scaled values.
The control range for line signals ranges between -20 dB and +16 dB. The control range for instrument signals ranges between -6 dB und +30 dB.
48V
The 48V switch activates the phantom power of 48 volts required for the use of
con- denser microphones.
Phantom power can be activated individually for both microphone inputs!
PAD
The PAD switch attenuates the signal of the microphone input by 20 dB, so that
even very high levels can be processed with the Channel One Mk3.
The phase reverse function reverses the polarity of the signal.
After pressing the switch, the phase is reversed by 180°.
A highpass filter with 6 dB per octave reduces impact noise below 80 Hz. This filter can be used for both preamplifiers.
OVL-LED
The OVL LED lights up as soon as an overload is detected in the device. The
indicator picks up at all relevant points of the signal flow: behind the
preamp, behind the tube saturation stage, behind the Transient Designer,
behind the compressor, behind the equalizer and behind the output control.
Tube Saturation
With this control the amount of tube saturation can be determined. In extreme
settings the level increases by only 6 dB.
Therefore decent to expressive harmonic distortions can be easily dialed in.
Tube Post
The Tube Post switch changes the order of the Tube Saturation within the
signal flow: When the switch is pressed, the Tube Saturation stage comes after
the EQ stage and before the output stage; when the switch is not pressed, the
Tube Saturation stage comes directly behind the preamp and before the de-
esser.
S-Reduction
The S-Reduction control adjusts the intensity of the S-sound reduction. In
practice, S-Reduction settings between -2 dB and -8 dB achieve the best
results for most applications.
The DE-ESS LED lights up as soon as an S-sound is detected.
It is only active when the de-esser is switched on, but it works independently
of the set reduction value. In other words, it always indicates that the
circuit is detecting sibilants – so your attention is always drawn to any need
for adjustment.
Low & High
The Low and High switches can be used to activate or deactivate the low or
high band de-esser, meaning a different center frequency for the de-esser. If
no switch is pressed, the de-esser is not active. If the Low switch is
pressed, the low de-esser band is activated with a center frequency of 6.4 kHz
and a bandwidth of 4.4 kHz. If the High switch is pressed, the high de-essing
band with a center frequency of 11.2 kHz and a bandwidth of 5.5 kHz is
activated. If both switches are pressed,Low and High band de-esser are active.
Attack
Attack can be used to increase or attenuate the transient phase of a signal by
up to 15 dB. A positive attack value increases the amplitude of the transient
response. Negative attack values lead to an attenuation.
Sustain
Sustain can be used to increase or attenuate the sustain phase of a signal by
up to 24 dB. Positive sustain values extend the sustain. Negative Sustain
values shorten the sustain.
The On switch activates the Transient Designer section, consisting of the Attack control and the Sustain control.
Compression
The Compression control can be used to set a threshold between 0 dB and -20
dB. The lower the threshold, the more the compressor works.
Make-Up Gain
The Make-Up Gain control can be used to make up for the overall level
reduction caused by compression.
A value between 0 dB and 20 dB can be set by which the level is increased
again after compression.
With the help of the Gain Reduction shown on the VU meter, the adjustment is
very simple: if the maximum reduction value caused by the loudest part is e.g.
-9 dB, the Make-Up Gain control should be set to values around +9 dB.
The On switch activates the compressor section, consisting of the compression control and the Make-Up Gain.
LMF
The center frequency of the half-parametric low/mid frequency filter is set
with the LMF control (low/mid frequencies).
The adjustable frequency range is between 30 Hz and 700 Hz so that this filter
covers a range of about 4.5 octaves,allowing it to be used from the deepest
bass to the lower mid-range. This together with the MHF filter ensures that
the entire frequency spectrum is covered.
The LMF filter operates to the proportional-Q-principle, in other words the
bandwidth is dependent on the selected boost or cut.
The -/+ control (right to the LMF control) determines the boost or cut of the
LMF filter.
The maximum values are at +/ – 12 dB.
MHF
The center frequency of the semi-parametric mid/high-frequency filter is set
with the MHF control. MHF: mid/high frequencies). The frequency range can be
set between 680 Hz and 15 kHz so that this filter covers a range of 4.5
octaves and can be equally be used in the lower mid as well as the high-
frequency range.
The MHF filter operates to the proportional-Q-principle, in other words the
bandwidth is dependent on the selected boost or cut.
The -/+ control (right to the MHF control) determines the cut of the MHF
filter.
The maximum values are at +/- 12 dB.
AIR
The high frequency filter in the equalizer module is labeled as AIR. A coil-
capacitor filter with so called bell characteristics and a center frequency of
19 kHz comes into operation here.
At this frequency the maximum possible accentuation is +10 dB, the maximum
possible damping is -10 dB.
The equalizer section is activated via the On switch.
EQ pre TD
The EQ pre TD switch swaps the order of the Equalizer and Transient Designer:
if the switch is pressed, the Equalizer is placed in front of the Transient
Designer; if the switch is not pressed, the order remains unchanged.
Output
With the output control, the output level can be attenuated by up to -20 dB or
amplified by a maximum of +6 dB. This ensures that following devices or AD
converters can receive an optimal output level.
The respective set output level is displayed on the big VU meter when the VU
switch is in the Out position.
Out 1 & Out 2
These balanced output connectors provide the output signal.
The Channel One Mk3 provides two parallel outputs each.
Preamp Out
This balanced preamp-out is not to be underestimated.
This output is the pure pre-amplified microphone signal – without any
processing of the Channel One Mk3’s processing tools.
Mute
The Mute switch mutes all output signals; when activated the VU meter displays
no output level (VU meter switch in Out position).
The VU-Meter
The illuminated VU meter displays the input level, output level and gain
reduction.
VU
The VU switch on the right below the VU meter can be used to select which
level is displayed in the VU meter.
- GR: Gain Reduction
- In: Input Level
- Out: Output Level
VU
For a better and more intuitive display of the signal levels the VU switch on
the left side below the VU meter can be adjusted to the display range of the
VU meter to different signal levels.
- In switch position 0, 0 dB on the VU meter corresponds to an output level of + 6 dBu.
- In the +6 switch position, 0 dB on the VU meter corresponds to an output level of +12 dBu.
- In the +12 switch position, 0 dB on the VU meter corresponds to an output level of +18 dBu.
Specifications
Analog inputs & outputs; XLR & TRS Jack (balanced)
Internal Linear Power Supply with Shielded Toroidal Transformer
Mains Power Supply
Dimensions & Weight
Reference: 0 dBu = 0.775V. All specifications are subject to change without notice.
The Channel One Mk3 can be ordered with an optional input transformer for the
microphone inputs and an output transformer for the output Out 1.
The product with both transformers installed is called:
Channel One Mk3 – Premium
Security Advices
Before starting up the device:
- Read thoroughly and follow the security advices.
- Read thoroughly and follow the Quickstart.
- Observe all warning instructions on the device.
- Please keep the user manual as well as the security advices in a safe place for future reference.
Warning
Always follow the security advices listed below to avoid serious injuries or
even deadly accidents due to electric shocks, short circuit, fire or other
dangers. The following are examples of such risks and do not represent an
exhaustive list:
Power supply/Power cord
- Do not place the power cord near heat sources such as heaters or radiators and do not excessively bend or otherwise damage the cord, do not place heavy objects on it, or place it in a position where anyone could walk on, trip over, or roll anything over it.
- Only use the voltage indicated on the device.
- Only use the supplied power cord/plug.
- If you intend to use the device in an area other than in the one you purchased it, the included power cord may not be compatible. In this case please contact your dealer.
- Be sure to connect the device to an appropriate mains socket outlet with a protective grounding connection.
- Improper grounding can cause electrical shock.
Do not open
- This device contains no user-serviceable parts. Do not open the device or attempt to disassemble the internal parts or modify them in any way. If it should appear to be malfunctioning, turn off the power immediately, unplug the power cord from the mains socket outlet and have it inspected by a qualified professional.
Water warning
- Do not expose the device to rain, or use it near water or in damp or wet conditions, or place anything on it (such as vases, bottles or glasses) containing liquids which might spill into any openings. If any liquid such as water seeps into the device, turn off the power immediately and unplug the power cord from the mains socket outlet. Then have the device inspected by a qualified professional.
- Never insert or remove an electric plug with wet hands.
Fire warning
Do not put burning items, such as candles, on the unit.
A burning item may fall over and cause a fire.
Lightning
Before thunderstorms or other severe weather, disconnect the device from the
mains socket outlet; do not do this during a storm in order to avoid life
threatening lightning strikes. Similarly, disconnect all the power connections
of other devices, antenna and phone/ network cables which may be
interconnected so that no damage results from such secondary connections.
If you notice any abnormality
When one of the following problems occur, immediately turn off the power
switch and disconnect the electric plug from the mains socket outlet. Then
have the device inspected by a qualified professional.
- The power cord or plug gets frayed or damaged.
- The device emits unusual smells or smoke.
- An object has fallen into the unit.
- There is a sudden loss of sound during the use of the the device.
Caution
Always follow the basic precautions listed below to avoid the possibility of
physical injury to you or others, or damage to the device or other property.
These precautions include, but are not limited to, the following:
Power supply/Power cord
When removing the electric plug from the device or an mains socket outlet,
always pull on the plug itself and not the cord. Pulling the cord may damage
it.
Unplug the device from the mains socket outlet when the device is not used for
a while.
Location
Do not place the device in an unstable position where it might accidentally
fall over.
Do not block the vents. This device has ventilation holes to prevent the
internal temperature from rising too high. In particular, do not place the
device on its side or upside down. Inadequate ventilation can result in
overheating, possibly causing damage to the device or even fire.
Do not place the device in a location where it may come into contact with
corrosive gases or salty air. This may result in malfunction.
Before moving the device, remove all connected cables.
When setting up the device, make sure that the mains socket outlet you are
using is easily accessible. If some trouble or malfunction occurs, immediately
turn off the power switch and disconnect the plug from the mains socket
outlet. Even when the power switch is turned off, electricity is still flowing
to the product at a minimum rate. When you are not using the device for a long
time, make sure to unplug the power cord from the wall mains socket outlet.
Connections
Before connecting the device to other devices, power down all devices. Before
power on or off the devices, set all volume levels to minimum.
Only use appropriate cables to connect the device with other devices. Make
sure that the cables you use are intact and comply with the electrical
specifications of the connection. Other connections can lead to health risks
and damage the equipment.
Handling
Operate the controls and switches only as described in the manual. Incorrect
adjustments outside safe parameters can lead to damage. Never use excessive
force on the switches or controls.
Do not insert your fingers or hands in any gaps or openings of the device.
Avoid inserting or dropping foreign objects (paper, plastic, metal, etc.) into
any gaps or openings of the device. If this happens, power down immediately
and unplug the power cord from the mains socket outlet.
Then have the device inspected by a qualified professional.
Do not expose the device to excessive dust or vibrations or extreme cold or
heat (such as direct sunlight, near a heater or in a car during the day) to
prevent the possibility of causing damage to the housing, the internal
components or unstable operation.
If the ambient temperature of the device suddenly changes, condensation can
occur (if for example the device is relocated or is affected by a heater or
air conditioning).
Using the device while condensation is present may result in malfunction. Do
not power on the device for a few hours until the condensation is gone. Only
then it is safe to power on.
Cleaning
Disconnect the device from your mains socket outlet before cleaning.
Do not use any solvents, as these can damage the chassis finish. Use a dry
cloth, if necessary, with an acid-free cleaning oil.
Disclaimer
Windows® is a registered trademark of Microsoft® Corporation in the United
States and other countries.
Apple, Mac and Macintosh are trademarks of Apple Inc., registered in the U.S.
and other countries.
The company names and product names in this manual are the trademarks or
registered trademarks of their respective companies.
SPL and the SPL Logo are registered trademarks of SPL electronics GmbH.
SPL cannot be held responsible for damage caused by improper use or
modification of the device or data that is lost or destroyed.
Notes on Environmental Protection
At the end of its operating life, this product must not be disposed with
regular household waste but must be returned to a collection point for the
recycling of electrical and electronic equipment.
The wheelie bin symbol on the product, user manual and packaging indicates
that.
For proper treatment, recovery and recycling of old products, please take them
to applicable collection points in accordance with your national legislation
and the Directives 2012/19/EU.
The materials can be reused in accordance with their markings. Through reuse,
recycling of raw materials, or other forms of recycling of old products, you
are making an important contribution to the protection of our environment.
Your local administrative office can advise you of the responsible waste
disposal point.
This directive only applies to countries inside the EU.
If you wish to discard devices outside the EU, please contact your local
authorities or dealer and ask for the correct method of disposal.
WEEE-Reg-No.: 973 349 88