K+H KPA 2290 User manual

Operating Manual
KPA 2220
KPA 2290
KPA 2400
Part Number: 528393
Version: 02
Date: 3-Jun-2009
Language: English, Française, Deutsch, Español
KPA Series
High Power Amplifier

Table of Contents
Introduction............................................................................................................................................................................... 5
Package Contents ..........................................................................................................................................................................5
More sound and less weight........................................................................................................................................................5
Superior Sound-Sonic Accuracy ..................................................................................................................................................5
Totally Digital with High Reliability............................................................................................................................................5
The Best Amplifier for Your Mains..............................................................................................................................................6
The KPA Series................................................................................................................................................................................6
Fully Featured Amplifier Range...................................................................................................................................................6
Installation and operation....................................................................................................................................................... 7
Unpacking .......................................................................................................................................................................................7
Mounting.........................................................................................................................................................................................7
Operating Precautions ..................................................................................................................................................................8
AC Mains connections ...................................................................................................................................................................8
Connecting Analog Inputs............................................................................................................................................................9
Connecting K8 Inputs..................................................................................................................................................................10
Connecting Outputs.....................................................................................................................................................................11
Connecting Remote Control .......................................................................................................................................................11
Setup and settings..................................................................................................................................................................12
Introduction..................................................................................................................................................................................12
The main screen...........................................................................................................................................................................12
The main menu ............................................................................................................................................................................13
Output attenuation.....................................................................................................................................................................14
Input Sensitivity...........................................................................................................................................................................14
Input select ...................................................................................................................................................................................14
Max output voltage.....................................................................................................................................................................15
Max mains current.......................................................................................................................................................................15
Clip limiter CH1 - CH2 ..................................................................................................................................................................15
Gate CH1 - CH2 .............................................................................................................................................................................15
Mute at power on ........................................................................................................................................................................15
Idle Mode.......................................................................................................................................................................................16
DSP Settings .................................................................................................................................................................................16
Bar meters.....................................................................................................................................................................................16
Output meters..............................................................................................................................................................................16
Temperature.................................................................................................................................................................................16
Mains meters................................................................................................................................................................................16
Amplifier Name ............................................................................................................................................................................17
Local preset...................................................................................................................................................................................17
Hardware info...............................................................................................................................................................................18
Hardware monitor .......................................................................................................................................................................19
LCD contrast..................................................................................................................................................................................19
Set keylock code ..........................................................................................................................................................................19
Menu locking ................................................................................................................................................................................19
Service............................................................................................................................................................................................20
The Smartcard function..............................................................................................................................................................20
Protection.................................................................................................................................................................................21
Turn-On/Turn-Off muting..........................................................................................................................................................21
Short circuit protection...............................................................................................................................................................21
Thermal protection......................................................................................................................................................................21
DC fault protection ......................................................................................................................................................................21
Input/Output protection ............................................................................................................................................................21
User maintenance...................................................................................................................................................................21
Cleaning.........................................................................................................................................................................................21
Removing Front Cover ................................................................................................................................................................21
Error Codes....................................................................................................................................................................................22
Guarantee.................................................................................................................................................................................22
EC Declaration of Conformity ................................................................................................................................................22
Technical notes........................................................................................................................................................................23
General Dimension.......................................................................................................................................................................23
Block diagram...............................................................................................................................................................................24
Technical specifications..............................................................................................................................................................25
Features.........................................................................................................................................................................................25
Safety and Warnings..............................................................................................................................................................26

Table des matières
Introduction.............................................................................................................................................................................27
Contenu du carton.......................................................................................................................................................................27
Plus de son, moins de poids.......................................................................................................................................................27
Une meilleure précision sonore.................................................................................................................................................27
Totalement numérique, haute fiabilité....................................................................................................................................27
Le meilleur amplificateur pour votre ligne secteur ...............................................................................................................28
La gamme KPA .............................................................................................................................................................................28
Une gamme d’amplificateurs offrant de nombreuses fonctions........................................................................................28
Installation et mise en service ..............................................................................................................................................29
Déballage.......................................................................................................................................................................................29
Installation et mise en place......................................................................................................................................................29
Précautions d’utilisation ............................................................................................................................................................30
Branchement secteur..................................................................................................................................................................30
Branchement des entrées analogiques ...................................................................................................................................31
Utilisation des entrées K8..........................................................................................................................................................32
Branchement des sorties............................................................................................................................................................33
Fonctions de télécommande......................................................................................................................................................33
Configuration et réglages......................................................................................................................................................34
Introduction..................................................................................................................................................................................34
L’écran principal...........................................................................................................................................................................34
Le menu principal ........................................................................................................................................................................35
Atténuation de sortie (Output atténuation)..........................................................................................................................36
Sensibilité d’entrée (Input Sensitivity) ...................................................................................................................................36
Sélection d’entrée (Input select) ..............................................................................................................................................36
Tension de sortie maximale (Max output voltage)...............................................................................................................37
Intensité secteur maximale (Max mains current) .................................................................................................................37
Limiteur de crête (Clip limiter) CH1 - CH2...............................................................................................................................37
Gate CH1 - CH2 .............................................................................................................................................................................37
Mute at power on ........................................................................................................................................................................38
Idle Mode.......................................................................................................................................................................................38
DSP Settings .................................................................................................................................................................................38
Bar meters.....................................................................................................................................................................................38
Output meters..............................................................................................................................................................................38
Temperature.................................................................................................................................................................................38
Mains meters................................................................................................................................................................................39
Affichage du nom de l’amplificateur .......................................................................................................................................39
Gestion des Presets dans la mémoire interne........................................................................................................................39
Hardware info...............................................................................................................................................................................40
Hardware monitor .......................................................................................................................................................................41
LCD Contrast .................................................................................................................................................................................41
Set keylock Code..........................................................................................................................................................................41
Verrouillage du menu..................................................................................................................................................................41
Service............................................................................................................................................................................................42
Fonctions relatives à la SmartCard...........................................................................................................................................42
Protection.................................................................................................................................................................................43
Mute à la mise sous tension/hors tension..............................................................................................................................43
Protection contre les courts-circuits ........................................................................................................................................43
Protection thermique..................................................................................................................................................................43
Protection composante continue..............................................................................................................................................43
Protection RF en entrée et en sortie ........................................................................................................................................43
Maintenance Utilisateur.........................................................................................................................................................43
Nettoyage .....................................................................................................................................................................................43
Démontage de la face avant......................................................................................................................................................43
Codes d’erreur ..............................................................................................................................................................................44
Garantie....................................................................................................................................................................................44
Déclaration de Conformité CE................................................................................................................................................44
Données techniques ...............................................................................................................................................................45
Dimensions générales.................................................................................................................................................................45
Synoptiques audio et alimentation..........................................................................................................................................46
Caractéristiques techniques ......................................................................................................................................................47
Caractéristiques ...........................................................................................................................................................................47
Sécurité et Avertissements ...................................................................................................................................................48

Inhaltsverzeichnis
Einleitung.................................................................................................................................................................................49
Lieferumfang................................................................................................................................................................................49
Mehr Klang und weniger Gewicht.............................................................................................................................................49
Hervorragender Klang – Akustische Präzision.......................................................................................................................49
Total digital bei hoher Zuverlässigkeit....................................................................................................................................49
Der beste Verstärker für Ihre Anwendung..............................................................................................................................50
Die KPA-Serie................................................................................................................................................................................50
Voll ausgestattete Verstärkerpalette ......................................................................................................................................50
Installation und Bedienung ...................................................................................................................................................51
Auspacken.....................................................................................................................................................................................51
Montage ........................................................................................................................................................................................51
Vorsichtsmaßnahmen beim Betrieb.........................................................................................................................................52
Netzanschluss ..............................................................................................................................................................................52
Analogeingänge anschließen ....................................................................................................................................................53
K8-Eingänge anschließen...........................................................................................................................................................54
Ausgänge anschließen................................................................................................................................................................55
Fernsteuerfunktion .....................................................................................................................................................................55
Einrichtung und Einstellungen..............................................................................................................................................56
Einleitung ......................................................................................................................................................................................56
Der Hauptbildschirm ...................................................................................................................................................................56
Das Hauptmenü ...........................................................................................................................................................................57
Output Attenuation / Ausgangsbedämpfung .......................................................................................................................58
Input Sensitivity / Eingangsempfindlichkeit..........................................................................................................................58
Input Select / Eingangswahl......................................................................................................................................................58
Max Output Voltage / Maximale Ausgangsspannung..........................................................................................................59
Max Mains Current / Maximaler Netzstrom............................................................................................................................59
Clip Limiter CH1 - CH2 / Clip Limiter Kanal 1 – Kanal 2.........................................................................................................59
Gate CH1 - CH2 / Gate Kanal 1 – Kanal 2 ................................................................................................................................59
Mute at power on / Stummschaltung beim Einschalten......................................................................................................60
Idle Mode / Leerlauf ....................................................................................................................................................................60
DSP Settings / DSP-Einstellungen ............................................................................................................................................60
Bar Meters / Balkenanzeigen ....................................................................................................................................................60
Output Meters / Ausgangsanzeigen........................................................................................................................................60
Temperature / Temperatur........................................................................................................................................................60
Mains Meters / Netzanzeigen ...................................................................................................................................................61
Amplifier Name / Verstärkername...........................................................................................................................................61
Local Preset / Lokale Presets.....................................................................................................................................................61
Hardware Info / Hardware-Info ...............................................................................................................................................62
Hardware Monitor / Hardware-Monitor..................................................................................................................................63
LCD Contrast / LCD-Kontrast .....................................................................................................................................................63
Set Keylock Code / Keylock Code einstellen............................................................................................................................63
Menu locking / Menü sperren....................................................................................................................................................63
Service / Wartung........................................................................................................................................................................64
Die Smartcard-Funktion .............................................................................................................................................................64
Schutz.......................................................................................................................................................................................65
Stummschaltung beim Ein-/Ausschalten ...............................................................................................................................65
Schutz vor Kurzschlüssen...........................................................................................................................................................65
Schutz vor Überhitzung..............................................................................................................................................................65
Schutz vor Gleichspannungsfehlern.........................................................................................................................................65
Schutz der Ein/Ausgänge...........................................................................................................................................................65
Wartung durch den Nutzer....................................................................................................................................................65
Reinigung......................................................................................................................................................................................65
Frontseite entfernen...................................................................................................................................................................65
Fehlercodes...................................................................................................................................................................................66
Garantie....................................................................................................................................................................................66
Konformitätserklärung ..........................................................................................................................................................66
Technische Hinweise...............................................................................................................................................................67
Allgemeine Abmessungen .........................................................................................................................................................67
Blockdiagramm ............................................................................................................................................................................68
Technische Daten.........................................................................................................................................................................69
Leistungsmerkmale.....................................................................................................................................................................69
Sicherheit und Warnhinweise ...............................................................................................................................................70

Índice
Introducción.............................................................................................................................................................................71
Contenido del paquete................................................................................................................................................................71
Más sonido con menos peso......................................................................................................................................................71
Sonido superior – perfección acústica .....................................................................................................................................71
Operación totalmente digital con un alto grado de confiabilidad......................................................................................71
El mejor amplificador para su equipo de sonido....................................................................................................................72
La serie KPA ..................................................................................................................................................................................72
Una amplia gama de amplificadores para todo tipo de situaciones..................................................................................72
Instalación y operación ..........................................................................................................................................................73
Para desempacar el producto....................................................................................................................................................73
Montaje..........................................................................................................................................................................................73
Cuidado..........................................................................................................................................................................................74
Conexión AC a la fuente de alimentación externa.................................................................................................................74
Conexión de las entradas analógicas.......................................................................................................................................75
Conexión de las entradas para el sistema K8.........................................................................................................................76
Conexión de las salidas...............................................................................................................................................................77
Conexión del control remoto .....................................................................................................................................................77
Ajustes y configuración..........................................................................................................................................................78
Introducción..................................................................................................................................................................................78
Pantalla principal.........................................................................................................................................................................78
Menú principal..............................................................................................................................................................................79
Output attenuation (atenuación de la salida) .......................................................................................................................80
Input Sensitivity (sensibilidad de entrada)............................................................................................................................80
Input select (modo de entrada)................................................................................................................................................80
Max output voltage (máximo voltaje de salida) ...................................................................................................................81
Max mains current (máxima corriente de entrada)..............................................................................................................81
Clip limiter CH1 - CH2 (limitador de clipping).........................................................................................................................81
Gate CH1 - CH2 (umbral de protección) ..................................................................................................................................81
Mute at power on (modo de silencio al encender la unidad)..............................................................................................82
Idle Mode (modo de reposo) .....................................................................................................................................................82
Funciones DSP ..............................................................................................................................................................................82
Medidores de barras....................................................................................................................................................................82
Medidores de salida ....................................................................................................................................................................82
Temperatura.................................................................................................................................................................................82
Medidores de la corriente externa............................................................................................................................................83
Nombre del amplificador............................................................................................................................................................83
Local presets (valores predeterminados) ...............................................................................................................................83
Información del hardware..........................................................................................................................................................84
Parámetros del sistema..............................................................................................................................................................85
Contraste de la pantalla LCD......................................................................................................................................................85
Código de activación ...................................................................................................................................................................85
Bloqueo de menús.......................................................................................................................................................................85
Servicio ..........................................................................................................................................................................................86
La función Smartcard..................................................................................................................................................................86
Sistemas de protección ..........................................................................................................................................................87
Silencio al encender y apagar la unidad..................................................................................................................................87
Protección contra cortocircuito .................................................................................................................................................87
Protección térmica.......................................................................................................................................................................87
Protección contra fallas en la señal de salida.........................................................................................................................87
Protección de entrada/salida ....................................................................................................................................................87
Mantenimiento........................................................................................................................................................................87
Limpieza ........................................................................................................................................................................................87
Quitando la cubierta frontal ......................................................................................................................................................87
Códigos de error...........................................................................................................................................................................88
Garantía....................................................................................................................................................................................88
Declaración de Conformidad CE ............................................................................................................................................88
Características físicas .............................................................................................................................................................89
Dimensiones .................................................................................................................................................................................89
Diagramas de conjunto...............................................................................................................................................................90
Especificaciones técnicas............................................................................................................................................................91
Características ..............................................................................................................................................................................91
Instrucciones de seguridad....................................................................................................................................................92

Klein + Hummel
Operating Manual KPA Series English 5
■Introduction
Thank-you for purchasing a Klein + Hummel KPA amplifier. Klein + Hummel amplifiers are designed to compliment
Klein + Hummel’s extensive range of Installed Sound equipment. No other amplifiers come close for applications
demanding high power and long term reliability. Thanks to amazing reductions in heat output along with
reductions in weight and the specific high output power, KPA amplifiers can be used in an unlimited range of
applications such as concert touring, opera houses, theatres, churches, cinema, theme parks, television sound
stages and industrial applications.
The KPA series amplifiers are fully compatible with all K8 digital audio distribution system input devices and may
be used to simply and easily create the highest quality, low noise audio connection without knowledge of
networking techniques.
Before reading the rest of this operating manual, review the safety and warnings. Note that imperial dimensions
are approximate.
Package Contents
The shipping carton contains:
•This operating manual
•The amplifier
•Product guarantee
•1 mains power cable (wire ends)
Features and accessories are listed at the end of this operating manual.
More sound and less weight
Compared to a conventional amplifier, Klein + Hummel KPA technology offers very high efficiency and delivers
more power to the loudspeakers with much reduced heat dissipation. This greater efficiency enables dimensions,
weight and power consumption to be reduced. The output stages of the amplifiers typically run at 95% efficiency,
dissipating only 5% of the input energy as heat.
One of the most interesting characteristics is that KPA’s efficiency is almost independent of output level.
Conventional amplifiers achieve their best efficiency only at full rated power output. Since standard music has an
average power density of 40% of the maximum level, conventional amplifiers can easily generate 10 times more
heat than KPA for the same volume of sound.
Superior Sound-Sonic Accuracy
Crystal-clear highs, and a tight, well-defined low end: the most accurate reproduction of an audio signal. Patented
design features ensure very high performance in parameters such as distortion, frequency response, slew rate,
power bandwidth and dumping factor.
Totally Digital with High Reliability
The KPA series is based on PWM technology that has been used for 30 years or more in power supplies and
inverters. PWM provides high reliability, small size, low weight and high efficiency. A PWM converter works as a
high frequency sampler, converting the variable amplitude (audio) signal into an impulse sequence with average
value equal to the audio input.
KPA amplifiers use very high sampling frequencies to obtain high performances across the audio band.

Klein + Hummel
Operating Manual KPA Series English 6
The Best Amplifier for Your Mains
The KPA series is fully Power Factor Corrected. This unique feature ensures that a predominantly resistive load is
presented to mains, minimizing current distortion and voltage/current displacement. This leads to much improved
performance of the amplifier at high levels of output and avoids mains-voltage collapses, typical of standard and
switching power supplies. Another great advantage of this technology is that its performance is, to a large extent,
independent of mains voltage. The rated output power does not vary with load/line conditions.
The KPA Series
KPA Series has many advanced features, digital control of many parameters, adjustable maximum mains
consumption, selectable digital presets and a graphic display that shows detailed information of the status of the
amplifier. You can appreciate the functionality of these and a lot of other features by reading this manual carefully.
Fully Featured Amplifier Range
KPA Series offers an extensive set of amplifier and load protection features and is designed to work under a wide
range of demanding conditions. It gives you unprecedented power and increased long-term reliability.

Klein + Hummel
Operating Manual KPA Series English 7
■Installation and operation
Unpacking
Carefully open the shipping carton and check for any noticeable damage; the
figure 1 below shows the exploded
view of the packing. Every Klein + Hummel amplifier is completely tested and inspected before leaving the factory
and should arrive in perfect condition. If you find any damage, notify the shipping company immediately. Be sure
to save the carton and all packing materials for the carrier’s inspection.
Mains cable
Manual
Amplifier
figure 1
Mounting
All KPA amplifiers are previewed for the standard 19” rack mounting; there are four front panels holes and four
rear lateral holes. The amplifiers must be fixed into rack in both sides, back and frontal, to avoid mechanical
damages. Your KPA amplifier uses a forced-air cooling system to maintain a low, even operating temperature.
Drawn by an internal fan, air enters through the slots in the front panel and courses over and through components.
The KPA series amplifiers feature an ”intelligent” variable-speed DC fan which is controlled by heat sink
temperature sensing circuits: the fan speed will increase only when the temperature of either heat sink requires it,
which keeps fan noise to a minimum and helps cut dust accumulation inside. Under extreme thermal load, the fan
will force a very large volume of air through the heat sinks. If either heat sink gets too hot, its sensing circuit will
reduce the output power. If the amplifier overheats, another sensing circuit shuts down its circuit to cut off power
until it cools to a safe temperature.

Klein + Hummel
Operating Manual KPA Series English 8
The exhaust cooling air is forced out through the rear of the chassis (
figure 2 ), so make sure there is enough space
around the sides of the amplifier to allow the air to escape. If it is rack mounted, make sure the exhaust air can flow
without resistance. If you are using a rack with closed backs, there must be at least one standard rack space of
opening in the front of the rack for every four amplifiers. Amplifiers may be stacked directly on top of each other
(no space needed between units), starting from the bottom of the rack.
figure 2
Operating Precautions
Make sure the AC mains voltage is correct and is the same as that printed on the rear of the amplifier. Damage
caused by connecting the amplifier to improper AC voltage is not covered by the warranty. Make sure the power
switch is off before making any input or output connections.
Whether you buy them or make them, use good-quality input and speaker cables. Most intermittent problems are
caused by faulty cables. Use good-quality connectors and wire, along with good soldering technique, to ensure
trouble free reliability.
AC Mains connections
The AC Main connection is made via the CPC type connector on the rear side of the panel. The
figure 3 below shows
the connection to the amplifier. Be sure that your AC mains power source has the requirements indicated in this
manual. The KPA amplifier has an automatic power factor correction system for a perfect mains network interface.
The amplifier is a resistive load for the mains network, minimizing the reactive power and the harmonic distortion
on the current. The system allows performance to be maintained even in circumstances of varying the mains
voltage.
It is important to connect the ground for safety, do not use adapters that disable the ground.
AC~ GND/ PEAC~
figure 3

Klein + Hummel
Operating Manual KPA Series English 9
■
Connecting Analog Inputs
Analog Input connections are made via the 3-pin XLR-female type or 1/4” phone Jack connectors on the rear side of
the amplifier. The polarity is shown in
figure 4 .
figure 4
The figure below shows the connection of analog input for balanced and unbalanced line. You can use both
configuration, but you must consider that unbalanced long line can introduce noise in the audio system. The Link
switch located in the rear panel is for direct paralleling the rear input connectors. You can use the remaining input
connector to carry signal to other amps.
/
Unbalanced input
SHIELD
IN(+)
IN(-)
IN(+)
GND
Balanced input
figure 5

Klein + Hummel
Operating Manual KPA Series English 10
Connecting K8 Inputs
ANALOG INPUTS
DIGITAL INPUT (OPTIONAL)
OUTPUTS
XLR ANALOG: 1= GND, 2= IN+, 3= IN-
JACK: SLV. = GND, TIP= IN+, RING= IN-
XLR AES/EBU: 1= GND, 2= IN+, 3= IN-
POS OUTPUT: 1+/2+ (PARALLEL)
NEG OUTPUT: 1-/2- (PARALLEL)
BRIDGEMODE: USE OUT1 1+/2+ and OUT2 1-/2-
ANALOG INPUTS
DIGITAL INPUT (OPTIONAL)
OUTPUTS
XLR ANALOG: 1= GND, 2= IN+, 3= IN-
JACK: SLV. =GND, TIP= IN+, RING= IN-
XLR AES/EBU: 1= GND, 2= IN+, 3= IN-
POS OUTPUT: 1+/2+ (PARALLEL)
NEG OUTPUT: 1-/2- (PARALLEL)
BRIDGEMODE: USE OUT1 1+/2+ and OUT2 1-/2-
ANALOG INPUTS
DIGITAL INPUT (OPTIONAL)
OUTPUTS
XLR ANALOG: 1= GND, 2= IN+, 3= IN-
JACK: SLV. = GND, TIP= IN+, RING= IN-
XLR AES/EBU: 1= GND, 2= IN+, 3= IN-
POS OUTPUT: 1+/2+ (PARALLEL)
NEG OUTPUT: 1-/2- (PARALLEL)
BRIDGEMODE: USE OUT1 1+/2+ and OUT2 1-/2-
ANALOG INPUTS
DIGITAL INPUT (OPTIONAL)
OUTPUTS
XLR ANALOG: 1= GND, 2= IN+, 3= IN-
JACK: SLV. =GND, TIP= IN+, RING= IN-
XLR AES/EBU: 1= GND, 2= IN+, 3= IN-
POS OUTPUT: 1+/2+ (PARALLEL)
NEG OUTPUT: 1-/2- (PARALLEL)
BRIDGEMODE: USE OUT1 1+/2+ and OUT2 1-/2-
K8 INK8 IN
K8 LINKK8 LINK
S W
KPA Series
K8 INDICATORS
S= Sync W= Wink
Please refer to manual for proper
K8 INDICATORS
S= Sync W= Wink
Please refer to manual for proper
K8 INDICATORS
S= Sync W= Wink
Please refer to manual for proper
K8 INDICATORS
S= Sync W= Wink
Please refer to manual for proper
ON
STANDBY
AES/EBU ANALOG
CLASS 2 WIRINGCLASS 2WIRING
21 43
TERM
+VDC GND+VDC GND
PUSH
PUSH
WARNING
To reduce the risk of fire
or electric shock, do not
expose this apparatus
to rain or moisture
WARNING
To reduce the risk of fire
or electric shock, do not
expose this apparatus
to rain or moisture
ANALOG IN1ANALOG IN1
OUT1
OUT2
ANALOG IN2
AES/EBU
ANALOG IN2
AES/EBU INPUT TIE ON OFFINPUT TIE ON OFF
figure 6
The KPA series amplifiers have K8 input and link connections built in as a standard feature. A K8 digital audio
distribution line may be connected to the K8 IN connection on the rear of the amplifier via a standard Cat5-cable
terminated with an RJ-45 connector. The LINK connection may be used to daisy chain the K8 bus to the next
amplifier or other K8 device.
Channel selection is made using rotary switches behind the front panel of the amplifier. Any stereo pair of the
available 16 audio channels on the K8 bus may be selected. For example, channels 1&2, 3&4, etc. may be selected.
figure 7
The LED labelled “S” on the K8 connector indicates that a good K8 signal is present on the bus and the amplifier is
Synchronized to it.
The LED labelled “W” on the K8 connector is used to Wink, or flash on and off, to identify the amplifier when being
remote controlled in software.
The K8 TERM switches must all be set to ON when the amplifier is the last device in the K8 daisy chain. When the
LINK connection is in use, the termination must be set to OFF.
Please see the user manual for the K8 input devices for more extensive information on how to use and configure a
K8 bus. The KPA amplifier is compatible with any K8 input device including K8-AESI16 AES digital inputs,
K8-AI8 analog inputs and K8-ESB Ethersound bridge as well as new ones being offered in the future.
Channel Select Switch

Klein + Hummel
Operating Manual KPA Series English 11
Connecting Outputs
Warning: there are lethal voltages at the loudspeaker connectors when the amplifier is turned on. To prevent any
damages turn the amplifier off before connecting the loudspeaker
Output connectors are made via neutrik speakon connectors. Consult the wire gauge chart to find a suitable wire
gauge to minimize power and damping factor losses in the speaker cables. The outputs can also work on bridge
mode. For each device the 1+ and 2+ pins of speakon connector are connected inside and have to be considered the
positive output of the channel; the 1- and 2- pins of speakon connector are connected inside and have to be
considered the negative output of the channel.
Note: Channel B is always polarity reversed output stage, but polarity compensated by feeding the minus pins of
the channel B output with the output voltage. Channel A is connected in the polarity mode. By having channel A
and B operating in opposite polarity, the energy storage in the power supply is more efficient. This is significant for
signals below 100Hz (sub bass etc.) and improves the power bandwidth.
Be sure to use balanced inputs on all measurement equipment (also oscilloscope probes) if you are bench testing.
OUT2IN 2 IN 1OUT1
CH1
OUT
stereo mode
brid
g
e mod
e
+
_
2+
2-
1-
1+
CH2
OUT
+
_
2+
2-
1-
1+
CH1
OUT
+
_
2+
2-
1-
1+
CH2
OUT
2+
2-
1-
1+
figure 8
Connecting Remote Control
Remote Control and remote power standby of the KPA series amplifiers will be available soon through the
K8 system interface. A firmware upgrade to existing amplifiers will make this additional feature possible.

Klein + Hummel
Operating Manual KPA Series English 12
■Setup and settings
Introduction
The
figure 9 below shows the front panel of KPA Series. The front panel controls, in conjunction with the graphic
LCD display above the buttons, give to the user the total control and detailed information about the status of the
amplifier. Each pushbutton has multiple functions and the display shows the current active function for each
button.
Read carefully the instructions below that help you to manage the functions of the amplifier.
-1
Signal
-2
-3
-6
-10
Clip
-1
Signal
-2
-3
-6
-10
Clip
K A B C D E F G H J I
AV/I-meter channel no 1 GGraphic LCD display
BSmartcard reader HV/I meter channel no 2
CFunction button no 1 IPower switch
DFunction button no 2 JTitle block
EFunction button no 3 KPanel unlocking
FFunction button no 4
figure 9
The main screen
The
figure 10 show the main screen; this screen appears after a short presentation when the user powers on the
amplifier. In the first line, after power on, the writing "WAIT" appears; if the system parameters are normal, the
writing are replaced with "READY". During the normal operation the controller monitors the system parameters. If a
parameter is out of range, the correspondent code error is written on the LCD meter of the relative channel in the
third line; if the abnormal parameter is associated to both channel, the error code is written in the centre.
figure 10
The LED bars can function as output voltage or output current meters; in the first case the LCD meters function as
output current meter, vice versa in the second case. The first green LED at the bottom side of the LED bar indicates,
when lighted, the presence of input audio signal above -60 dBV on the corresponding channel; the 2nd, 3rd, 4th and
5th LED in the ascending order indicates an output level of -3dB, -6dB and -10dB respectively. The green LEDs will be
lighted during normal working. The yellow LED will light at -1 dB. If the level of the audio signal reach the channel
output capability, red LED will be triggered.
The LED bars have diagnostic function also; a flashing yellow LED indicates a critic range of temperature
(from 80°C to 85°C) of the power devices on the corresponding channel, if this LED is lighting constantly, the
temperature is above 85°C. A lighting constantly red LED indicates that the corresponding channel is under
protection and in this case the writing ”PROT” appears in the first line of the display.

Klein + Hummel
Operating Manual KPA Series English 13
The fourth line of the screen shows the functions of the buttons below.
The ”lock” function is activated if the corresponding button is pressed more than 1 second; in this case all the other
buttons are locked. The same operation unlocks these buttons (unlock code is required - see par. “local preset” for
more details).
The ”mute” buttons switch off the two channels independently; in this case the parameters of the correspondent
channel disappear and the writing ”muted” appears on the third line. The same operation disables the mute
function.
If the ”menu” button is pressed, the main menu is displayed on the LCD screen.
The main menu
The
figure 11 shows the main menu. You can scroll the menu items by pushing the up or down buttons and choose
the selected one by pushing ”ok” (if the chosen item enables or disables a function, the writing ”on” is replaced
with ”off” for disabling it, or ”on” for enabling it. The menu tree is shown in
figure 12 .
figure 11
Menu Settings Output attenuation
Input gain/sens
Input select
Max output voltage
Max mains current
Clip limiter CH1
Clip limiter CH2
Gate CH1
Gate CH2
Mute at Power on
Display Bar meters
Output meters
Temperature
Mains meters
Setup Hardware info
Hardware monitor
LCD contrast
Amplifier Settings
Idle Mode
DSP Settings (or not present) *
Network Settings (or not present) **
Amplifier Name
Setup Hardware info
Hardware monitor
LCD contrast
Local presets Recall local preset
Save local preset
Set Keylock code
Menu locking
Service
Analog=>DSP=>Out *
AES3=>Out *
AES3=>DSP=>Out *
K8=>Out
K8=>DSP=>Out *
Analog=>Out
* Avai lable only with opti onal DSP board
figure 12
Se t t i n g s
Displa y
Local Preset

Klein + Hummel
Operating Manual KPA Series English 14
To better handle the huge amount of parameters, the single value numeric input mode is extended with a
fine/coarse feature. When you edit one of the parameters, you will start in the “fine” mode. The steps applied by
the - and + keys are the minimum allowable for that parameter. By clicking the “fast” key shown in
figure 13 , you
will switch in the “coarse” mode, and the key will be renamed as “slow” as shown in
figure 14 . In the coarse mode,
the steps are equivalent to 10 steps of the fine mode, so that editing will be 10 times faster. Remember that by
keeping the - or + key pressed, the steps are automatically repeated.
figure 13
figure 14
Output attenuation
The figure 15 shows the Output attenuation screen. You can choose to set CH1, CH2 or both by pushing the ”C1+2”
button. The ”+” and ”-” buttons change the value of the output attenuation in the range
from 0 to -30dB.
Note: for the best sonic performance it is preferred to set the 0db output attenuation (no attenuation), and select
the proper gain/sensitivity by the following menu.
figure 15
Input Sensitivity
You can choose among three different input modes (if available): Gain 35 dB, 32 dB, 29 dB and 26 dB. The up and
down buttons change the selection; the ”sel” button locks the selected option.
Input select
You can choose among six different input modes (if available): Analog, Digital AES*, K8* with or without
DSP processing. The up and down buttons change the selection; the ”sel” button locks the selected option.
* Available only with optional DSP board
Max mains current
22 A rms
M
axma
i
ns curren
t
22 A rms
dB
-13
Output attenuation
-13

Klein + Hummel
Operating Manual KPA Series English 15
Max output voltage
You can choose to set CH1, CH2 or both by pushing ”C1+2” button. The ”+” and ”-” buttons change the value of the
max output peak voltage.
figure 16
Max mains current
The
figure 17 shows the Max mains current screen. The ”+” and ”-” buttons change the value of the max mains
current input in the range from 15 to 32A. Maximum mains current limit set the rms value at which a C-Type
current breaker will trip-off.
figure 17
Clip limiter CH1 - CH2
Enable this function to prevent the distortion due to excessive amplitude of output signal. You can enable/disable
it by pushing the on/off button.
CAUTION: There is the risk of damage to the loudspeakers, if Clip Limiters are deactivated. You should not
deactivate Clip Limiters unless their function is taken over by external devices, such as digital system controllers. In
such cases it is mandatory, to properly adjust parameters in the external device.
Gate CH1 - CH2
This function allows to mute the amplifier channels individually if input signal amplitude is falling below the values
shown in the following table. You can enable/disable it by pushing the on/off button. Gating the output is delayed
by 5 seconds after input signal removal, and follows in reversed way the bottom green LED on the CH1, CH2 bar LED
display *(muted if green LED is off).
Threshold Values Of Input Signal Detector
dBV dBu mVrms
26 -54 -52 2
29 -57 -55 1,41
32 -60 -58 1
GAIN (dB)
35 -63 -61 0,707
figure 18
Mute at power on
If enabled, the amplifier will be always in mute state for both channels at power on; you can mute off the channels
independently in the main screen, but in this mode the amplifier will be in the mute state at the next power on.
M a x m a ins c urre nt
22 A rms
V
peak
102
Max output voltage
102

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Operating Manual KPA Series English 16
Idle Mode
The idle mode function is a power saving feature. By activating it, if the amplifier doesn’t detect the signal for the
user defined amount of time, the output stage is turned off, saving about 40 W of power per channel. This means
reduced heating, longer amplifier and fans life, and, especially for fixed installation permanently turned on, a lower
electricity bill.
DSP Settings
This sections is implemented if optional DSP board is present.
Bar meters
In the Bar meters screen you can choose if the LED bars operate as output voltage meter and LCD bar in the main
screen as output current meter (by selecting ”LED Volt, LCD Curr), or vice versa (by selecting the other item).
Output meters
In the Output meters screen you can view the values of the output signal for CH1 and CH2. Furthermore, the
impedance of the load is showed in the bottom line of the screen (see
figure 19 ). Minimum of output voltage for
impedance measurements is 10 Vrms, measurements values are stored into logbook. Time between single
impedance measurements can be up to several minutes depending on program signal. Output power is shown as
maximum value every 200 ms. In "C1+2" mode the screen shows the output values in bridge connection.
figure 19
Temperature
In the Temperature screen you can view the historic temperature diagram of the last four hours of the final current
use in the range from 10 to 90°C; in the bottom-right side of the screen there is the present value
(see
figure 20 ).
figure 20
Mains meters
In the Mains meters screen you can view the voltage and the current of the mains (see figure 21 ).
figure 21
0 Arms
0 Vrms
0 Watt
Mains meters
170 Vrms
20 Arms

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Operating Manual KPA Series English 17
Amplifier Name
The amplifier name, together with the current preset name, can be displayed by enabling the “Display amplifier
data” function. The 20 characters amplifier name, together with the 40 characters preset name is shown in a
different way when the amplifier is in the starting page of the main menu. The amplifier name can be assigned by
the “Edit amplifier name” command (for the text editing, see Local preset handling section).
Local preset
There is the possibility to store up to 50 presets on amplifier local memory.
By choosing the Save local preset command, the current amplifier configuration (basic amplifier settings + DSP
board settings if DSP board is present) is stored on the local memory. To proceed, the menu asks to choose one of
the 50 available presets (see
figure 22 ), showing the preset number and name. If the preset was never used, it is
named <empty>. By pressing ok, you can enter the preset name. The selected character is pointed by the arrow
shown in
figure 23 , and by pressing or + keys it is modified. By pressing the key, next character is selected as
shown in
figure 24 . When the name input is finished, by pressing the ok key, the preset is stored
figure 22
figure 23
figure 24
Select preset # 1
<empty>
Ch
oose prese
t
na me
PRESET 1
^
C
hoose pre se t na m e
18 SET1
^

Klein + Hummel
Operating Manual KPA Series English 18
The Recall local preset command loads and applies one of the stored presets, chosen through an identical dialog.
Please note that all the current amplifier settings are overwritten! Note that if you have already input a preset
name, or if you have loaded a preset from local memory or smart card, the name is kept by the amplifier and used
as starting point for a new save preset operation. For example, suppose that you have loaded a preset named
“18IN SUB 1” from a SC, and then you save it into local memory as shown in
figure 25 . In this case the menu shown
in
figure 26 asks you if you want to keep/edit that name (shown figure 27 ) or if you would like to edit the name of
the preset that is going to be overwritten (shown
figure 28 ). This is useful for copying presets from/to smart card.
figure 25
figure 26
figure 27
figure 28
Hardware info
In this screen you can view some information about the hardware of the amplifier:
•S/N the serial number of the amplifier
•HW ID the hardware identifier (always 00)
if you push the ”more” button, you can view the other info
•KFRNT the version number of the front panel
•KCTRL the version number of the controller
•KDSP the version number of the DSP board
•K8 the version number K8 adapter
if you push the ”more” button, you can view the other info
•Lifetime the operating time of the amplifier
S
e
l
ec
t
prese
t
#3
Exi st i ng Pre se t
Ke e p t h i s n a m e ?
18IN SUB1
Ch
oose preset name
^
18IN SUB1
Choose preset name
^
Exi st i n g Pre