Krix Seismix 5, Seismix 3 User Manual

Owner’s Manual

Seismix 3 and Seismix 5

Congratulations on choosing Krix

The Seismix 3 and Seismix 5 active subwoofers will complement existing Stereo or Home
Theatre systems producing an increase in low frequency performance for a deep experience.
The Seismix 3 and Seismix 5 are compatible with a variety of small to large sized, sealed
or vented, main/satellite speakers.

Your subwoofer contains an amplier of the highest electronic standards. Krix have introduced
In Circuit Serial Programming (ICSP), meaning the microcontroller within the amplier can be
upgraded via the serial interface located internally on the amplier module. This means as
future features are developed your subwoofer can be upgraded. You would simply need
to return the amplier module to Krix, where the upgrade would take place.

Figure 1 Back panel of subwoofer

Volume Control

Low Pass Control

Line Level Inputs

Speaker Level
Input/Outputs

Mains Power Switch

Figure 2 Connection using LineLevel signal

To main

Main AV Receiver

From pre-out
or sub-out

If only a single or mono sub-out
exists, then plug that into the left
Line Level input labelled mono

Figure 3 Connection using SpeakerLevel signal

stereo speakers

+ - - +

To main stereo speakers

connection

1. Ensure the main power switch is off

and connect the mains power cord.

2. There are two methods which you can use

to connect the Seismix subwoofer, either
via the line level inputs which will require
your stereo amplier / AV receiver to have
a subwoofer output facility (mono or stereo
outputs) or via the speaker level inputs.

 Method 1: Line Level Connections

It is recommended that you use LineLevel

connections for home theatre applications.
Connect the SUB OUT socket(s) on your
AV receiver to the LineLevel input(s)
which are a pair of RCA sockets located
in the middle of the rear subwoofer panel
(see gure 1). The SUB OUT socket on your
AV receiver is usually mono which can be
connected to the Seismix with one lead
to the ‘Left (mono)’ input. If your AV receiver
has stereo SUB OUT sockets then use dual
leads, connecting these to the ‘Left and
Right’ inputs. Refer to gure 2 for connection
using LineLevel signal.

 Method 2: Speaker Level Connections

For stereo applications connect the Speaker

Level outputs on your main amplier to the
SpeakerLevel inputs on the rear panel of

the Seismix (see gure 1). Then connect
the SpeakerLevel outputs on the rear panel
of the Seismix to each of your left and right
speakers. Be sure to maintain correct phasing
for each set of speaker leads, red (positive +)
to (+) and black (negative -) to (-). Refer
to gure 3 for connection using Speaker
Level signal.

3. Before turning the Seismix on, ensure the

volume control is turned down and set the
LowPass(Hz) control to the middle position
(see gure 1). Turn on the unit with the
power switch located at the bottom of the
rear panel, the subwoofer will activate and
the blue Power/Standby LED will light up.
Begin by playing music with bass content
and slowly increase the volume dial on the
subwoofer to a moderate level.

Main Stereo Amplier

+ - - +

features

Automatic on / off circuit

Standby Mode

Symetrix Vent

Clipping protection

- Opto-compressor with fast attack
to prevent overload

- Soft limiting to prevent amplier clipping

Multi-layered fault protection

- DC Detect Sensor

- Thermal Sensor

- Mains Fuse

Electronic ltering

- Earth lift switch to eliminate ground loops

- 2nd order low pass lter adjustable
from 60Hz to 150Hz

- Adjustable Hi / Lo gain setting

- 0°/180° phase switch

- Fixed 2nd order high pass lter to
reduce driver excursion below 30Hz

Independent adjustable gain control

Heavy duty, high efciency long throw
paper cone drivers designed for high level
sound reinforcement

High current low noise amplier

Automatic On / Off Circuit

For the auto circuit function to operate, the
power switch on the back of the subwoofer
needs to be left on (and can be done so safely,
see gure 1). The AutoCircuit monitors both
the speaker level or line level inputs and powers
the amplier in the subwoofer. When a signal
is present the blue Power/Standby LED at
the top of the rear panel will remain lit. When
a signal is not present, the power will remain
on for approximately 15 minutes and will then
automatically switch itself to standby mode.
In standby mode the blue Power/Standby
LED will ash.

Warning:itisrecommendedthattheunit
isturnedoffatthemainspowerifbeing
leftunattendedforanyextendedperiods.

Standby Mode

Krix have included an energy saving device
when the unit is in Standby mode, meaning
the Seismix draws a meagre 3 watts (costing
approximately AUD$5.00 for 1 year to run).

Symetrix Vent

The Seismix subwoofer enclosure features
Symetrix bass reex venting, with the vent
exhibiting the same are radius both internally
and externally. This lowers subwoofer distortion
and serves to reduce vent turbulence or
“chufng” at high drive levels.

Clipping Protection

There are several layers of protection in
the electronics of the Seismix to prevent
clipping damage.

Opto-compressor: When faced with a signal

peak which is in excess of what the Seismix
can accurately reproduce, a compressor circuit
activates to reduce the level of the signal once
it passes the preset threshold. This permits the
Seismix to perform at high level with only a
mild reduction in the signal’s dynamic content.

Soft Limiter: If severe overdriving of the

amplier continues to place a strain on the
compressor circuit, a soft limiting circuit
activates. The soft limiter circuit monitors
the Seismix’s amplier power supply voltage
and prevents a direct current (DC) signal from
reaching the bass driver, causing damage.

Fault Protection

The mains fuse protects against any
major electrical faults or short circuits
and incorporates an inrush current limiter
to eliminate power surges when using the
main on / off switch. The Seismix uses an
ATMEL MEGA16® microcontroller which is
the integrated circuit responsible for the
advanced fault protection features of the
Seismix amplier. A microcontroller is a small
single chip computer optimised for hardware
control that runs a program stored in ash
memory on the chip. The construction of
the Seismix amplier utilises surface mount
technology (SMT), which results in a more
compact design, high resistance to mechanical
vibration and higher circuit performance. The
lter capacitor bank present in the Seismix
amplier features many low Equivalent Series
Resistance (ESR) capacitors allowing lower
supply impedance and greater instantaneous
power delivery to the loudspeaker load.

DC Detect Sensor: Clipping is severe square

wave distortion that contains a direct
current (DC) component often responsible
for loudspeaker damage. In the event of an
abnormal function the amplier will not only
shut down, but all LED’s will ash. If this
happens turn the subwoofer off and contact
your nearest Krix retailer for further assistance.

Thermal Sensor: The Seismix has a generously

sized heat sink, permitting normal operation
in high ambient temperatures. A thermal
sensor internally connected to the heat
sink is monitored every 20 seconds by the
microcontroller. In the unlikely event that
the amplier’s temperature reaches above
65 degrees celsius the microcontroller
will reduce output by 1dB every 20 seconds
until the temperature is 65 degrees celsius
or below. The microcontroller will return
the amplier to normal operating settings
by increasing the output by 1dB every
20 seconds.