KAM KXT 22350 User manual

KAM KXT AMPLIFIER
professional power amplifier
INSTRUCTION MANUAL
www.kam.co.uk

OVERVIEW
Your KXT Amplifier is a high quality, high power professional PA amplifier with an
additional 3rd channel. It is ideal for powering a 2.1 system comprising a single Sub Bass
speaker and a pair of passive satellite speakers. We know you're itching to get it fired up
but bear with us and we'll run through a few things you should know that will help you get
the best from your new amplifier and ensure that it lasts as long as you want it to.
There are two models in the KXT Amplifier range
KXT 22350 2 x 300W RMS + 500W RMS @ 4 Ohms
2 x 200W RMS + 350W RMS @ 8 Ohms
KXT 23600 2 x 450W RMS + 900W RMS @ 4 Ohms
2 x 300W RMS + 600W RMS @ 8 Ohms
SAFETY NOTE
ALWAYS turn off the mains power before making any connections to KX Pro amplifiers.
Large PA amplifiers are capable of sending potentially lethal amounts of electricity to
their outputs so you should always ensure that any amplifier has its power turned off
(and preferably disconnected) before making connections. NEVER attempt to connect a
microphone to the speaker outputs of an amplifier.
WHICH SPEAKERS ARE RIGHT FOR YOUR AMPLIFIER?
Power & Impedance
It is important to ensure that you match the power that your speakers can handle with
the power that your amplifier can produce. A set of speakers has two stated ratings.
They should have a 'Power' handling capacity that is measured in Watts (EG 300W).
This tells you how much power the speaker can handle from the amplifier before the
sound distorts and damage begins to occur. This is often stated as two different ratings;
'RMS' which means how much power can be handled constantly… and 'Peak' which as
the name suggests means an amount of power it can handle for a short period of time.
A speaker will also have what we call an 'Impedance' rating. Impedance is a term we use
to define the amount of resistance your speaker presents to your amplifier and it is
measured in 'Ohms'. Most speakers have an Impedance rating of 8 Ohms but ratings of
4 Ohms are not uncommon and sometimes you may encounter 16 Ohm or even 2 Ohm.
A speaker that is rated at 8 Ohm presents a larger amount of resistance to the
amplifier than one that is rated at 4 Ohm. As you can see from the chart below this
means that a particular amplifier will deliver greater power to a pair of 4 Ohm speakers
than it would to a pair of 8 Ohm speakers.
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KAM KXT23600 PROFESSIONAL POWER AMPLIFIER
KXT 23600 POWER AMP
KXT 23600 POWER AMP
NOTE Connecting multiple speakers to a single amplifier alters the impedance rating of the
speakers. For guidance on this visit www.kam.co.uk/tuition.
KXT amplifiers require speakers with a minimum Impedance rating of 4 Ohm.
They will work just as well with speakers rated at 8 Ohm but the volume achieved from
your speakers will be different for 4 and 8 Ohm speakers. The chart below tells you the
power output ratings for KXT amplifiers at 4 and 8 Ohms.
FRONT PANEL CONTROLS
[1] Mains Power switch - use this to switch the mains power on/off.
[2] Power LED - when the power is on the blue power LED will light.
[3] Volume controls - used to adjust overall volume for each channel.
[4] Signal Indicator LEDs - each channel has a single green Signal Indicator LED which
lights whenever a signal is present.
[5] Clip Indicator LED - each channel has a single red Clip Indicator LED which only
illuminates when an excessive signal is present.
An optimum operating level is one where the Signal Indicator LED lights to show that the
amplifier is working and the Clip indicator LED lights very occasionally.
[6] Protect LED - these amber LEDs illuminate when one of the following 'Protection'
mechanisms has engaged;
KXT 22350
KXT 23600
Stereo
2 x 300W RMS
2 x 450W RMS
Sub
500W RMS
900W RMS
4 Ohm speaker 8 Ohm speaker
2
4
5
6
Stereo
2 x 200W RMS
2 x 300W RMS
Sub
350W RMS
600W RMS
1
3
2

Thermal Protection
KXT amplifiers feature a thermally efficient dual heat sink design and dual speed, dual
fan cooling. They are designed to operate in the kind of relatively high environmental
temperatures found in some venues and we feel that they perform extremely well in such
hostile conditions. However, because extremely high environmental temperatures are
always a hazard to high power amplifiers, all KXT amplifiers also feature a Thermal
Protection Relay. If the amplifier becomes too hot, it will temporarily go into a 'standby'
mode where the audio circuitry (but not the fans!) is switched off. This gives the circuitry
time to cool down. If this happens the amber LEDs marked 'Protect' (found on the front
panel) will illuminate. If this happens you should turn the volume controls to zero
immediately and wait. When the Protect LEDs stop being illuminated you can gradually
return the volume controls to the desired listening level. Under such circumstances it is
advisable to return the volume controls to a slightly lower listening level than that set
prior to the engagement of the Thermal Protection Relay. The more power output you
demand from your amplifier, the higher the internal operating temperature is liable to
be… so a lower listening level will decrease the chances of the Relay engaging
once more.
Short Circuit Protection
The KXT Amplifier range also features Short Circuit Protection that temporarily
disables the unit in the event of an electrical short circuit within your PA system.
Short circuits are usually caused by damaged cables but can, on rare occasions, also be
caused by excessive atmospheric moisture. Excessive moisture is caused either by
direct exposure to rain or by operation within an extremely humid atmosphere
(everything in the venue will be dripping wet) and if experienced the remedy is to cease
to use the unit and to leave it to dry out naturally. If damaged cables are to blame,
turning the unit off, waiting for a few minutes and then turning it back on will not remedy
the situation and you will need to use the services of a professional to trace the fault.
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REAR PANEL CONTROLS
[7] Balanced XLR audio inputs - use these balanced XLR line level audio inputs to connect
any line level audio device such as a DJ Mixer, Mixing Console, CD player etc.
For more information on the advantages of using balanced audio connections visit
www.kam.co.uk/tuition.
[8] Unbalanced 1/4” Jack audio inputs - use these unbalanced 1/4” Jack line level audio
inputs to connect any line level audio device such as a DJ Mixer, Mixing Console,
CD player etc.
[9] RCA Phono type audio inputs - use these unbalanced RCA Phono type line level audio
inputs to connect any line level audio device such as a DJ Mixer, Mixing Console, CD
player etc.
[10] Channel 3 Input Select switch - Channel 3 Input Select switch – when this switch is
in the ‘CH3’ position, amplifier channel 3 receives audio signals from the channel 3 audio
inputs. When the switch is in the ‘CH1+CH2’ stereo input position, channel 3 takes
audio signals from a inputs 1 & 2. The purpose of this is to enable use of channel 3
to drive a Sub Bass speaker when you only have stereo input from your mixer etc.
[11] Channel 1&2 speaker outputs - use these Speakon Type connectors to attach your
Mid/High or Full range speakers. KX Pro Speakon terminals are wired in a +2/-2
configuration.
[12] Channel 3 speaker output - use this single (red) Speakon type connector to attach
your Sub Bass Speaker.
POWER
PRO
CLIP
SIGNAL
POWER
PRO
CLIP
SIGNAL
2
POWER
PRO
CLIP
SIGNAL
3
7
8
9
10
11
12
13
14
15
16
17
4

About Crossovers
The idea of a 'two way' speaker (which is what most 'full range' speakers are) is usually
that the speaker cabinet houses two separate actual speaker drivers. It is common for
one to be dedicated to reproducing High frequencies and the other to be dedicated to
reproducing Low and Mid range frequencies. In order to make this work it is necessary
to split the incoming audio signal in such a way that only High frequencies are sent to
the High Frequency tweeter and only Low/Mid frequencies arrive at the Low/Mid driver.
The device used to split the signal is called a 'Crossover'. It is common when assembling
a more powerful PA system to have either a 'three way' system consisting of 3 separate
speaker cabinets (1 each for Low, Mid & High frequencies) or a two way system where
several full range speaker cabinets are augmented by an additional Sub or Bass speaker.
In such set ups it is also necessary to employ Crossovers to divide audio signals so that
the right PA system components receive only the right audio frequencies.
[13] Sub Woofer Crossover switch - use this switch to turn the channel 3 Crossover
on/off.
[14] Sub Woofer Crossover Frequency control - when the Sub Woofer Crossover is on,
use this control to adjust the Crossover Cutoff Frequency. Only frequencies below the
Crossover Cutoff Frequency will be sent to channel 3.
[15] Low Cut Filter controls - use this to switch the Low Cut Filter on/off to remove low
frequency rumble etc to deliver an uncluttered low/mid sonic response.
There are 3 positions; Bypass where the Low Cut is not active, 30Hz where all
frequencies below 30Hz are removed, 50Hz where all frequencies below 50Hz
will be removed.
[16] Limiter switch - use this to switch the built in Limiter circuit on/off. When in the on
position the audio signal will be automatically prevented from exceeding the maximum
signal level beyond which clipping (distortion) will occur and the Peak LEDs will light.
[17] Ground Lift switch - When using Unbalanced audio input connections you may, in
some circumstances experience problems with persistent hum. This can be caused by
an 'earth/ground loop'. Using this 'ground lift' switch disengages the ground (aka earth)
connection from the mains power to the amplifier and can help in some circumstances.
The problem is rare with correctly configured Balanced audio connections.
You will find loads more advice and information about setting up Kam audio equipment
within the Tuition area at www.kam.co.uk.
Thank you for reading these guidelines and enjoy your Kam KXT amplifier!
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KXT22350 power amplifier
Amplifier power output
2 x 300W RMS + 500W RMS @ 4 Ohms
2 x 200W RMS + 350W RMS @ 8 Ohms
Input connections Balanced XLR, unbalanced jack, RCA Phono
Output connections Speakon
Minimum impedance 4 Ohms
Frequency response 20Hz - 20KHz (±1.5dB)
S/N Ratio 80dB
THD 0.1%
Soft Start
AC/DC Protection
Limiter Circuit
Short Circuit Protection
Thermal Protection
2 x dual speed cooling fans
Min input sensitivity 770mv/0dB
Input impedance 20k Ohm balanced & 10k Ohm unbalanced
Dimensions 482 x 473 x 88mm
Weight 22Kg
KXT23600 power amplifier
Amplifier power output
2 x 450W RMS + 900W RMS @ 4 Ohms
2 x 300W RMS + 600W RMS @ 8 Ohms
Input connections Balanced XLR, unbalanced jack, RCA Phono
Output connections Speakon
Minimum impedance 4 Ohms
Frequency response 20Hz - 20KHz (±1.5dB)
S/N Ratio 80dB
THD 0.1%
Soft Start
AC/DC Protection
Limiter Circuit
Short Circuit Protection
Thermal Protection
2 x dual speed cooling fans
Min input sensitivity 770mv/0dB
Input impedance 20k Ohm balanced & 10k Ohm unbalanced
Dimensions 482 x 473 x 88mm
Weight 24Kg
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www.kam.co.uk