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.

Earth Lift

The EarthLift button ensures the Seismix
can be connected to a wide range of stereo
ampliers / AV receivers. Should a humming
noise be evident when the Seismix is connected,
push the EarthLift button (see gure 1) which
interrupts the current that may be circulating from
the subwoofer’s signal ground through the mains
earth wiring (see gure 4). Note: The EarthLift

button does not break the mains earth connection
to the subwoofer, only the connection between
the subwoofer’s signal ground and the mains
earth. To guard against electric shock NEVER
disconnect the mains earth from any appliance.

Low Pass (Hz)

The LowPass control (see gure 1) adjusts
the total bass content from the Seismix. This
control allows you to adjust the upper limit of the
Seismix’s frequency range between 60 –150 Hz.
The higher the selection, the broader the range
of bass information heard. This setting can be
adjusted for personal taste and integration with
your main speakers.

Figure 4 Earth lift button

Mains power outlets

Circulating ground currents

Earth lift button

+

+

Signal connection

2

1

0

-1

-2

2

1

0

-1

-2

= =

Negative going

= =

Subwoofer

Figure 5 Phase

2

1

0

-1

-2

2

1

0

-1

-2

Positive going

Hi / Lo Gain

The Hi/LoGain button (see gure 1) is
positioned below the blue Power / Standby
LED, this button allows you to increase or
decrease the sensitivity of the subwoofer
without adjusting other settings. In the ’Lo’
gain position, a much higher input signal is
required, and you will need to increase the
main volume control to reach maximum output.

In the ’Hi’ gain position the output of the
subwoofer is increased by approximately 20dB,
requiring a lower input signal, meaning you will
not need to increase the main volume control
to achieve the same amount of output.

Phase

Signal phase can be left at '0°', or shifted
180° (inverted), by pressing the Phase button
(see gure 1). This applies to the output of
the subwoofer compared to its input.

Denotes chassis Earth

Denotes signal ground

Receiver / Amplier

2

1

In Phase

180° out
of phase

-1

-2

-1

-2

0

2

1

0

(No output)

To get the most from all of your speakers they
must be operating in Phase. That is the signals
must all be positive going or negative going
simultaneously. If this is not the case and one
signal is positive going and the other is negative
going the result will be a cancellation of signal
and the sound at those particular frequencies
will be perceived as quite 'empty' sounding
and lacking potential impact.

The setting of the Phase button (ie. 0° or
180°) and the resulting sound is dependant
on where the subwoofer is positioned in
relation to the main speakers. The best way
to nd the correct setting is through trial and
error during set up by comparative listening
tests. In most cases the effect will be subtle
and there won't be a complete lack of bass.
If no difference can be heard, the position
of the button is not crucial.

The effect of phase can best be shown with
the representation of a sine wave (see gure

5). The effect shown in the lower diagram is
with the signals 'out of phase' and this can be
rectied by changing the position of the Phase
button. This will invert the negative going
signal and the result will be the same as
the rst, 'In Phase', example.

Line Level Inputs

Line level inputs (see gure 1 or 2) need to
be connected to the ‘PRE OUT’ or 'SUB OUT’
from your stereo amplier / AV receiver.
The line level stereo input performs a summing
function adding the left and right signals where
applicable, to give a mono (L+R) signal. This
mono signal is ltered and then amplied
before being sent to the subwoofer driver.

Speaker Level Inputs

The speaker level stereo inputs combine
the signal going to the main left and right
speakers providing a mono (L+R) signal to
the subwoofer driver. This mono signal is
ltered and then amplied in the same
way as the line level input signal before being
sent to the loudspeaker. Two pairs of terminals
are provided so that the speaker level signals
can “pass through” the subwoofer on the way
to the main speakers (see gure 1 or 3).

Volume

The volume control will adjust the volume
of the subwoofer only. The control can be
set for the subtleties of the lower octaves
in musical performances or increased for
the earth shattering explosions and effects
on movie sound tracks. The volume control
on your main amplier / AV receiver controls
volume for your overall system (see gure 1).

positioning

The procedure for setting up any subwoofer
can be time consuming, requiring numerous
minor adjustments to get the desired result.
There is no denitive 'correct' way to set up a
subwoofer. Given different listening environments
different people’s tastes and different speakers,
there are a number of variables that have to be
taken into consideration.

It is up to the individual listener to adjust
the Seismix for the character and strength
of bass that is preferred for whatever type
of source material is being reproduced.

It is benecial to select music that is familiar
to you when carrying out listening tests and
setting up procedures and as a suggestion
play recordings that use wooden instruments
such as acoustic guitars, oboes, cello etc.
These instruments exhibit a strong resonant
characteristic in the low to mid bass region
and will highlight unpleasant ‘woody’ or ‘chesty’
sound qualities suggesting there is too much
overlap in the bass information between the
subwoofer and main speakers.

To ne tune the integration of the Seismix into
your Hi- system, start with both the LowPass
(Hz) and Volume at the middle setting. Gradually
adjust the setting of the LowPass(Hz) either
up or down (see gure 1). This will vary the
amount of overlap from the sub to the main
speakers and increase or decrease the level at
those frequencies. The effect is a strengthening
or weakening of the upper bass region. You might
reach a point where the sound develops a 'boxy'
or 'chesty' quality which is not desirable. This
could indicate there is too much overlap from
the sub to the main speakers and is remedied
by turning the LowPass(Hz) back. Adjust the
Volume level to suit your personal taste.

trouble shooting

Symptom Probable Cause Treatment

No noise from the
subwoofer when
main power is on

Very little bass coming
from the subwoofer

Bass content is
too strong and
uncomfortable
to listen to

Subwoofer emits
a humming sound

If you have any queries regarding the Seismix, the set up procedure or any other KRIX
product, please contact your nearest Krix retailer or Krix direct. Contact details are on
the back cover of this booklet.

Auto switch circuit has not
operated due to no signal

Volume turned down

Signal has no bass content

Apart from the source
material having little bass
content, the settings on the
sub may need adjustment

Settings on the subwoofer
may need adjustment

Current may be circulating
from the subwoofer’s signal
ground through the mains
earth wiring.

Play source material and
gradually increase the volume
from the main Hi- amplier

Increase Volume on the sub

Play source material with
sufcient bass content

Increase setting of the
LowPass(Hz) control

Try changing position of
the Phase button

Increase Volume on the sub

Change gain button from
‘Lo’ to ‘Hi’

Decrease the setting of
the LowPass(Hz) control

Decrease the Volume on
the subwoofer

Activate the EarthLift by
pushing the button which
will break the current loop

warranty

5 years warranty applies to the cabinet and speaker
1 year warranty applies to the amplier and related internal electronics

(Refer to the details on the warranty card supplied)

Seismix 3: specications

Drivers

Bass Driver Nominal 255mm (10”) diameter paper cone driver developed for

high level, low frequency reinforcement

Electronics

Amplier Power 200 watts RMS into the nominal 4 ohm driver

Maximum instantaneous power 400 watts
Amplier S/N >70dB
Distortion - Input to Speaker <0.1% - @ 80 watts RMS
Line Level Inputs Left Input (mono) Lo – 900mV RMS for maximum output

Hi – 100mV RMS
Left + Right Input (stereo) Lo – 450mV RMS for maximum output
Hi – 50mV RMS

General

Frequency Range 22Hz - 150Hz (-6dB) in room response
Output 120dB maximum SPL in room response
Auto Power On / Off 15 minute delay before switching to standby after no input signal
Phase Select 0° or 180° (relative to input signal)

Cabinet

Enclosure Type Bass reex, front vented
Dimensions 415mm high x 360mm wide x 390mm deep
Material 17mm MDF
Finish Vinyl or lacquered timber veneer
Weight 18kg

Due to continued development specications may change without notice

Seismix 5: specications

Drivers

Bass Driver Nominal 305mm (12”) diameter paper cone driver developed for

high level, low frequency reinforcement and large linear cone travel

Electronics

Amplier Power 400 watts RMS into the nominal 4 ohm driver
Maximum instantaneous power 800 watts
Amplier S/N >70dB
Distortion - Input to Speaker <0.1% - @ 80 watts RMS
Line Level Inputs Left Input (mono) Lo – 900mV RMS for maximum output

Hi – 100mV RMS
Left + Right Input (stereo) Lo – 450mV RMS for maximum output
Hi – 50mV RMS

General

Frequency Range 16Hz - 150Hz (-6dB) in room response
Output 122dB maximum SPL in room response
Auto Power On / Off 15 minute delay before switching to standby after no input signal
Phase Select 0° or 180° (relative to input signal)

Cabinet

Enclosure Type Bass reex, front vented
Dimensions 460mm high x 395mm wide x 440mm deep
Material 19mm and 25mm MDF
Finish Vinyl or lacquered timber veneer
Weight 30kg

Due to continued development specications may change without notice

Krix Loudspeakers Pty Ltd

14 Chapman Road

Hackham SA 5163
Australia

T 61 8 8384 3433

F 61 8 8384 3419
[e-mail]

krix.com