Klein + Hummel K8-AI8 User manual

Operating Manual
Manuel Utilisateur
Bedienungsanleitung
K8-AI8 K8-AO2
K8-AO8 K8-ESB
K8
Digital Audio Distribution System

Page 2 K8 ackmount Family User Manual
Safety Instructions
It is absolutely essential that you read these safety instructions carefully before connecting and
using this K+H product. Your safety depends on it. Failure to follow these instructions voids the
warranty.
To ensure safe operation for years to come, keep these instructions in a safe place for future reference. K+H has
manufactured this product in accordance with IEC 92 (SEC) 39 standards, then tested and delivered it in safe operating
condition. To maintain it in this condition, you must:
• observe all safety instructions
• use the product only as described herein
• have any maintenance, repairs, or modifications performed only by K+H or other authorized personnel
• ensure that the room in which you use this product is wired in accordance with the local electrical code
Warning!
Warning!Warning!
Warning!
• When the interior of the cabinet is exposed, touching some parts can lead to an electric shock.
• If you need to gain access to the interior electronics of the unit, always disconnect the unit from any and all
power sources first.
• Any repairs, maintenance, or other service of the unit when its interior compartment is exposed may only be
performed safely (in accordance with VBG 4) by authorized technicians familiar with all the risks involved. Even
in an unplugged state, a risk of electric shock is possible.
Fig. A
• If you need to replace any fuses, ensure that the replacements are of exactly the same type, value and voltage
as the originals, as spelled out in the technical specifications at the rear of this manual.
• Do not use "repaired" fuses.
• If you do not have fuses of the specified size, type and value, do not hot-wire the contacts in the holder by
short-circuiting them.
• Certain areas of the cabinet, cover, and rear panel can achieve extreme temperatures and are therefore marked
with a "HOT" label (Fig. B). efrain from touching any heat sink or ventilation grille.
• High volume levels are known to cause permanent - i.e. irreversible - hearing damage, especially when listened
to without sufficient breaks. The higher the levels, the more frequent and extended must be the breaks. Avoid
standing too close to loudspeakers that are being driven at high levels. If you must be exposed to high sound
pressure levels over an extended period of time, use hearing protection.
Fig. B
Mains Connection:
Mains Connection:Mains Connection:
Mains Connection:
• This unit is designed for continuous operation.
• Ensure that the operating voltage of the unit matches that of the local mains current (AC line voltage).
• Always check before connecting the power cable to the mains socket that the power switch on the unit itself is set to off
("O").
• Use the power cable or power supply that came with the unit to connect to the mains socket (wall outlet).
• Power supply: a damaged power cable may not be repaired. Use a new cable.
• Avoid plugging the mains cable into a power strip that already has several other power-consuming devices connected to
it.
• Avoid using extension cables. The unit must be connected to a mains socket close to it, and that socket should be freely
accessible.
Installation:
Installation:Installation:
Installation:
• Installation and overhead rigging of this product must be conducted by a qualified professional according to applicable
local, national and international codes and standards. Mounting brackets supplied by the manufacturer must be
attached to appropriate hardware and attachment points rated and intended for such use.
• Do not expose this product to vibration.
• Do not operate this product anywhere near water or other liquids. Do not use it near a sink, swimming pool, bathtub, or
in any damp room or area. Electrical shocks carried through water can kill. Do not place any beverages whatsoever on or
near this product, as liquids can kill electronic components.
• Ensure sufficient ventilation around the product to allow for adequate heat dissipation, especially near the rear panel
and the sides of the cabinet (minimum of 8 inches from the nearest wall). The unit may only be installed in a rack if
measures are taken to ensure sufficient ventilation and if the mounting instructions of the manufacturer are followed.
Do not block or cover any heat sink, fan, or vent.
• Keep this product a safe distance away from radiators and other heaters of any kind.
• If you bring this product from a cold environment into a warm one, it is quite possible that condensation will form inside
the cabinet. Please allow the unit sufficient time for acclimation to room temperature (minimum thirty minutes) before
connecting and powering up.
• To avoid accidents, do not use any accessory equipment with this product that is not approved by the manufacturer,
particularly mounting accessories.
• Do not place this unit on any unstable platform, cart, stand or table. If the unit falls, it can cause bodily injury to persons,
or can be damaged itself.
• To protect this product from lightning damage during a thunderstorm or from power surges during an extended
absence, disconnect the power cable from the wall outlet.

K8 ackmount Family User Manual Page 3
Table of Contents
Safety Instructions 2
K8 Product Family Operating Manual 5
K8 Series Overview............................................................................................................................................5
Quick Start Information....................................................................................................................................5
Using Input Devices...........................................................................................................................................5
Using Output Devices........................................................................................................................................5
Connecting a Control System...........................................................................................................................
Monitoring with a PC.........................................................................................................................................
Category 5 Cable Color Code ............................................................................................................................
Frequently Asked Questions (FAQ) ................................................................................................................
Manufacturer’s Declarations 7
CE Declaration of Conformity...........................................................................................................................7
K8-AI8 Product Manual Section 8
Rear Panel Description......................................................................................................................................8
Front Panel Description ....................................................................................................................................8
Overview .............................................................................................................................................................9
Stacking Input Devices .....................................................................................................................................9
Termination Setting ..........................................................................................................................................9
Control and Monitoring ....................................................................................................................................9
Input Level Settings ....................................................................................................................................... 10
Front Panel LEDs ............................................................................................................................................. 10
Compatible Accessories ................................................................................................................................. 10
K8-AI8 Technical Specifications ................................................................................................................... 11
Electrical ........................................................................................................................................................... 11
Mechanical........................................................................................................................................................ 11
K8-AO8 Product Manual Section 12
Rear Panel Description................................................................................................................................... 12
Front Panel Description ................................................................................................................................. 12
Overview .......................................................................................................................................................... 12
Routing Capabilities ....................................................................................................................................... 13
Stacking Output Devices ............................................................................................................................... 13
Termination Setting ....................................................................................................................................... 13
Control and Monitoring ................................................................................................................................. 13
Output Level Settings .................................................................................................................................... 13
Front Panel LEDs ............................................................................................................................................. 14
Compatible Accessories ................................................................................................................................. 14
K8-AO8 Technical Specifications.................................................................................................................. 15
Electrical ........................................................................................................................................................... 15
Mechanical........................................................................................................................................................ 15

Page 4 K8 ackmount Family User Manual
K8-AO2 Product Manual Section 16
Rear Panel Description................................................................................................................................... 1
Front Panel Description ................................................................................................................................. 1
Overview .......................................................................................................................................................... 17
Routing Capabilities ....................................................................................................................................... 17
Stacking Output Devices ............................................................................................................................... 17
Termination Setting ....................................................................................................................................... 17
Control and Monitoring ................................................................................................................................. 17
Output Level Settings .................................................................................................................................... 17
Front Panel LEDs ............................................................................................................................................. 18
Compatible Accessories ................................................................................................................................. 18
K8-AO2 Technical Specifications.................................................................................................................. 19
Electrical ........................................................................................................................................................... 19
Mechanical........................................................................................................................................................ 19
K8-ESB Product Manual Section 20
Rear Panel Description................................................................................................................................... 20
Front Panel Description ................................................................................................................................. 20
Overview .......................................................................................................................................................... 21
Rack Mounting ................................................................................................................................................ 21
Routing Capabilities ....................................................................................................................................... 21
Stacking Input Devices .................................................................................................................................. 21
Termination Setting ....................................................................................................................................... 22
Control and Monitoring ................................................................................................................................. 22
Compatible Accessories ................................................................................................................................. 22
K8-ESB Technical Specifications................................................................................................................... 23
Electrical ........................................................................................................................................................... 23
Mechanical........................................................................................................................................................ 23

K8 ackmount Family User Manual Page 5
K8 Product Fa ily Operating Manual
ead this section first as it explains the overall system theory of all K8 devcies in the family. Additional
manual sections contain the details for specific model number.
K8 Series Overview
K8 is a digital audio distribution system. It allows for the transport of 16 digital audio signals over a single
Category 5 cable along with control data. The audio signal travels in one direction only, from the input
device to the output device. Control data is bi-directional.
Quick Start Information
K8 devices are factory configured to begin passing audio immediately after powered up in the simple case
where 8 input channels are sent to 8 output channels. More complex settings and configurations are
possible if desired by using the K8 terminal control protocol. For example, configuring an 8 channel output
device to select channels 9-16 instead of 1-8 is done using the K8 terminal control protocol.
Using Input Devices
Input devices are used to put audio onto the K8 bus while output devices are used to get audio out of the
K8 bus.
Two 8-channel devices may be stacked up to populate all the available 16 channels on a K8 cable. For
example, 16 analogue inputs are obtained by stacking quantity (2) K8-AI8 devices.
Stacking two devices is accomplished using a standard Ethernet crossover cable to connect the K8 Out 2 of
the first device to the K8 Out 1 of the second device. The K8 Out 1 of the first device is then used to drive
the K8 bus.
K8 Out 1
K8-AI8 Analogue Input
K8 Out 2
K8 Out 1
K8-AI8 Analogue Input
K8 Out 2
Term
On
Not Used
Term
On
Cat 5 Crossover Cable
Out to
Distribution
K8 Channel Inputs 9-16
K8 Channel Inputs 1-8
Using Output Devices
TE MINATION ULE: The first and last device on each K8 chain must have their termination switches set. If
both K8 ports on a device are used, the 4 switches are on. If one of the K8 ports on a device is not
connected, the switches are off. The K8 terminal control protocol is able to monitor the termination switch
settings remotely.

Page 6 K8 ackmount Family User Manual
Input devices are used to put audio onto the K8 bus while output devices are used to get audio out of the
K8 bus.
Output devices may be daisy chained until the maximum cable length of 200 meters has been reached.
Output devices are passively connected and do not refresh the K8 audio signal. This architecture has the
benefit that a failure of an output device will still allow audio to pass to the next device in the chain. Daisy
chaining devices introduces no delay in the audio signal.
Connecting a Control System
The status of all K8 devices in a system may be remotely controlled and monitored through the S-485
port on the input device. The control signal passes through the same cable as the audio signals and
requires no special installation. The protocol is openly published on www.klein-hummel.com for use by
software engineers and control system programmers.
Monitoring with a PC
It is possible to monitor and control the devices in a K8 system using a terminal program and the K8
terminal control protocol. Instructions for its use are available on the website at www.klein-hummel.com.
Some K8 devices are connected to the PC with an S-485 port and some are connected with an Ethernet
port. It is possible to purchase a USB/485 adapter. Please refer to the section of the manual for this
specific device.
Category 5 Cable Color Code
The K8 system utilizes the same cabling and pin standards as Ethernet, although K8 is not an Ethernet
protocol.
K8 system cables should be terminated according to standard TIA/EIA-568A or standard TIA/EIA-568B.
Both standards create a straight through cable as long as the same color code standard is used on both
ends. Creating a crossover cable is accomplished by terminating one end as 568A and terminating the
opposite end as 568B.
Frequently Asked Questions (FAQ)
What is K8?
What is K8?What is K8?
What is K8?
K8 is an easily implemented and robust method of distributing digital audio and control signals across a
facility or between two audio devices with low latency and professional audio quality.
What audio format is used in K8?
What audio format is used in K8?What audio format is used in K8?
What audio format is used in K8?
Currently available products are uncompressed digital 24 bit, 48 kHz sample rate.
How many channels are available w
How many channels are available wHow many channels are available w
How many channels are available with K8?
ith K8?ith K8?
ith K8?
Up to 16 audio channels may be placed on a single cat 5 cable, as two sets of 8.
How are the cables terminated?
How are the cables terminated?How are the cables terminated?
How are the cables terminated?
All cables are terminated with J-45 connectors using the color code defined by either EIA-568A or EIA-
568B as long as all ends are terminated using the same standard.
How do I get 1 audio channels on the K8 system when the input box K8
How do I get 1 audio channels on the K8 system when the input box K8How do I get 1 audio channels on the K8 system when the input box K8
How do I get 1 audio channels on the K8 system when the input box K8-
--
-AI8 only has 8 inputs?
AI8 only has 8 inputs?AI8 only has 8 inputs?
AI8 only has 8 inputs?
Up to two input units such as the K8-AI8 (analogue line input) may be used to place audio onto the K8
bus. One of the two input units must be connected to the system via a standard category 5 crossover
cable.
How do I make a cat 5 crossover cable?
How do I make a cat 5 crossover cable?How do I make a cat 5 crossover cable?
How do I make a cat 5 crossover cable?
Wire one end according to the color code EIA-568A and the other end according to the color code EIA-
568B. In the K8 system a crossover cable is used to stack two input devices such as the K8-AI8 onto the
same cable. All other cat 5 cables are wired straight through.

K8 ackmount Family User Manual Page 7
How far can you run a K8 cable?
How far can you run a K8 cable?How far can you run a K8 cable?
How far can you run a K8 cable?
One K8 distribution leg can be run a total length of 200 meters no matter how many devices are connected
along the way.
How much delay is in the K8 system?
How much delay is in the K8 system?How much delay is in the K8 system?
How much delay is in the K8 system?
K8 has a total through delay of 1/2 ms. Adding K8 output devices adds no delay to the signal path
because all K8 devices, except for distribution amplifiers, are passive.
If a single K8
If a single K8 If a single K8
If a single K8 device fails does the whole system go with it?
device fails does the whole system go with it?device fails does the whole system go with it?
device fails does the whole system go with it?
No. K8 devices are passive and a single failure will not destructively affect any other device on the system.
How do I control K8 devices?
How do I control K8 devices?How do I control K8 devices?
How do I control K8 devices?
The K8 system is a single cable solution for both audio and control. A K+H terminal protocol is available
for connecting a PC. The control system protocol is also openly published for use with Stardraw, AMX,
Crestron and other control systems.
Do K8 devices need to have addresses assigned to them?
Do K8 devices need to have addresses assigned to them?Do K8 devices need to have addresses assigned to them?
Do K8 devices need to have addresses assigned to them?
No, it is not required to make address assignments to K8 devices. Because all 16 channels of audio are
present everywhere on the bus all the time it is not necessary to specify an audio destination address. At
the factory all devices are assigned an address based on their serial number for control and monitoring
purposes. This ensures that no address conflicts will happen on the control bus when first connecting the
system. Control addresses may be changed and text names may be assigned to K8 devices using the
control protocols.
Can K8 be used in a star topology?
Can K8 be used in a star topology?Can K8 be used in a star topology?
Can K8 be used in a star topology?
K8 can be implemented in either a daisy-chain, star or hybrid topologies. Star topologies are accomplished
using active K8 distribution amplifiers (available 2008) to drive each leg of the star.
Is K8 compatible w
Is K8 compatible wIs K8 compatible w
Is K8 compatible with EtherSound?
ith EtherSound?ith EtherSound?
ith EtherSound?
K+H offers bridging interface boxes to map EtherSound channels onto the K8 distribution system.
When do I use EtherSound and when do I use K8?
When do I use EtherSound and when do I use K8?When do I use EtherSound and when do I use K8?
When do I use EtherSound and when do I use K8?
EtherSound is best utilized when high audio channel counts are required and when interfacing between
K+H and other manufacturer’s EtherSound enabled gear. K8 can operate as a stand-alone technology in
smaller systems. In larger EtherSound systems, K8 operates as distribution branches off the core
EtherSound trunk where only 16 audio channels are adequate.
Manufacturer’s Declarations
CE Declaration of Conformity
This equipment is in compliance with the essential requirements and other relevant provisions of
Directives 89/336/EC and 73/23/EC. The declaration is available on the internet site at www.klein-
hummel.com. Before putting the device into operation, please observe the respective country-
specific regulations!

Page 8 K8 ackmount Family User Manual
K8-AI8 Product Manual Section
Rear Panel Description
INPUT 8
INPUT 7
INPUT 1 INPUT 2 INPUT 4INPUT 3
INPUT 5
INPUT 6
-10dBV
+4dBu
48
96
Overload
Cal
1 2 3 4 5 6 78
RS 485
21
K8 OUT
TERM
AC IN 100-240V AC, 5 0-60 Hz
Max. Pow er Consum ption 15Wa tts Made in Germany
Wink
Ok
K8
K8K8
K8-
--
-AI8 ear Panel
AI8 ear PanelAI8 ear Panel
AI8 ear Panel
Input 1
Input 1Input 1
Input 1-
--
-8
88
8 Balanced analogue audio line inputs.
S 485
S 485S 485
S 485 emote control connector for PC or external control system connection.
OK LED
OK LEDOK LED
OK LED Glows green after the unit has started up and the analogue-to-digital converters are
running.
Wink
Wink Wink
Wink LED
LEDLED
LED Light blinks when turned on by remote control software. This light may be used to
confirm that a device is being remote controlled.
DIP (
DIP (DIP (
DIP (-
--
-10 / +4)
10 / +4)10 / +4)
10 / +4) This DIP switch sets the input sensitivity for each of the inputs independently. The
two choices are –10 dBV for consumer music players and +4 dBu for professional
audio equipment. Other input levels are possible using the Cal trim pots.
DIP (48/96)
DIP (48/96)DIP (48/96)
DIP (48/96) This DIP switch is not currently used. The sampling rate is fixed at 48kHz until future
notice.
Cal
CalCal
Cal Used to adjust the input sensitivity of each of the Input channels independently.
Used in conjunction with the DIP switch above.
TE M
TE MTE M
TE M DIP switch is used to terminate the device when only one of the two output ports are
being used. The device is terminated when the switch is set to ON. All switches must
be set the same way, either to ON or OFF!
K8 OUT 1 and 2
K8 OUT 1 and 2K8 OUT 1 and 2
K8 OUT 1 and 2 K8 digital audio bus outputs. Each one contains the same audio and control data and
each one is capable of driving a 200 meter line. When only one output is used the
termination switch must be set to ON.
Overload LED
Overload LEDOverload LED
Overload LED The Overload LED turns on when any of the analogue-to-digital Inputs are
overloaded. The output of the audio source device will need to be turned down or
the input level trim adjusted with the Cal and DIP switch level settings.
Power Switch
Power SwitchPower Switch
Power Switch Turns the power to the unit off and on.
Earth Terminal
Earth TerminalEarth Terminal
Earth Terminal The ground terminal is a connection to the audio circuit ground/earth. This is
directly tied to the chassis ground.
Front Panel Description

K8 ackmount Family User Manual Page 9
0
-20
+12
0
-20
+12
0
-20
+12
0
-20
+12
0
-20
+12
0
-20
+12
0
-20
+12
0
-20
+12
POWER
2 3 4 5 6 7 8
INPUT 1
ANALOGUE LINE INPUT
K8 DIGITAL AUDIO DISTRIBUTION
K8- AI8
K8
K8 K8
K8-
--
-AI8 Front Panel
AI8 Front PanelAI8 Front Panel
AI8 Front Panel
Power LED
Power LEDPower LED
Power LED The Power LED is illuminated when the device is plugged in and the rear power
switch is turned on.
Input LEDs
Input LEDsInput LEDs
Input LEDs The red, yellow and green channel Input LEDs show the input signal strength for each
channel downstream of the Cal and DIP switch rear panel level trim adjustments.
Overview
The K8-AI8 is a K8 input device allowing 8 analogue audio channels to be placed onto the K8 bus.
Stacking Input Devices
Two AI8 devices may be stacked to populate all 16 available audio channels. Alternately, the AI8 may be
combined with any other 8 channel input device for a total of 16 channels.
Using a crossover cable connect the Out 2 of the first device to the K8 Out 1 of the second device. The K8
Out 1 of the first device is then used to drive the K8 bus.
K8 Out 1
K8-AI8 Analogue Input
K8 Out 2
K8 Out 1
K8-AI8 Analogue Input
K8 Out 2
Term
On
Not Used
Term
On
Cat 5 Crossover Cable
Out to
Distribution
K8 Channel Inputs 9-16
K8 Channel Inputs 1-8
Termination Setting
The 4 termination switches must all be set to “on” when the AI8 is the first device in the K8 chain.
Both K8 output ports connected: Termination Off
One K8 output port connected: Termination On
Control and Monitoring
All devices on the K8 bus may be controlled and monitored through a single S-485 connection to the AI8
device. The protocol is openly published on www.klein-hummel.com for use by software engineers and
control system programmers. The pinout of the S-485 port is as follows:

Page 10 K8 ackmount Family User Manual
PIN 1 Phantom Ground
PIN 2 Phantom Power
PIN 3 Data A (+)
PIN 4 Data B (-)
PIN 5 Signal Ground
PIN 6-9 Not Used
The phantom power is used to drive K8 accessories designed to attach to the local control connector, such
as a local volume control wall plate. Phantom power is switched off by default and must be activated
through the control protocol.
Input Level Settings
The AI8 is shipped from the factory to accept a +4 dBu nominal input level with the peaks no greater than
+20 dBu.
For connection of devices with unbalanced CA connections, such as CD or MP3 players, a rear mounted DIP
switch allows each individual channel to be set to an input level of –10 dBV.
For other input levels less than +20 dBu peak, a recessed screw turn potentiometer can be used to exactly
trim each channel to the desired input level. An overflow LED indicator next to the adjustments shows
when the analogue to digital converter has been saturated.
Front Panel LEDs
Each input channel has 3 front panel LEDs to show channel level. The green LED illuminates at signal
present 32 dB below digital full scale. The yellow LED illuminates at nominal level 12 dB below digital full
scale. The red LED illuminates just before the onset of clipping. Brief illuminations of the red LED are
acceptable in normal operation.
The AI8 input meters show the analogue signal level after it has been adjusted by the DIP switch and
adjustment pot settings, just before it is converted to digital.
Compatible Accessories
K8
K8K8
K8-
--
-485
485485
485 USB to S-485 adaptor cable for using a PC to program K8 system devices.
K8
K8K8
K8-
--
-***
******
*** A variety of input and output signal types are available and always growing.
DB9 Female Control Connector

K8 ackmount Family User Manual Page 11
K8-AI8 Technical Specifications
Electrical
Frequency esponse
Frequency esponseFrequency esponse
Frequency esponse 20 Hz – 22 kHz
Signal to Noise atio
Signal to Noise atioSignal to Noise atio
Signal to Noise atio >100dB(A)
Input
InputInput
Input Balanced analogue audio, XL -1/4” female combo connector x 8
Input Level
Input LevelInput Level
Input Level +22 dBu peak
-10 dbV to +4 dBu nominal input level adjustments
Output
OutputOutput
Output Two K8 bus outputs, each drives 200 meters
Control
ControlControl
Control S-485, DB-9 female connector, open published protocol
38400 Baud, 8 Data, 1 Stop, No Parity
Optional USB adaptor
Optional Ethernet adaptor
Termination Switch
Termination SwitchTermination Switch
Termination Switch 4-position DIP
Digital Audio Format
Digital Audio FormatDigital Audio Format
Digital Audio Format 48 kHz sampling rate, 24 bit, proprietary
Latency
LatencyLatency
Latency ½ millisecond worst case, analogue in to analogue out
Power equirements
Power equirementsPower equirements
Power equirements 100 – 240 Volt, 50-60Hz
15 Watts
IEC power cord connector
Front Panel Indicators
Front Panel IndicatorsFront Panel Indicators
Front Panel Indicators Power
Signal present, signal nominal level, signal peak level
ear Panel Indicators
ear Panel Indicatorsear Panel Indicators
ear Panel Indicators OK, Wink
Mechanical
Weight
WeightWeight
Weight 7 lbs / 3,2kg
Dimensions
DimensionsDimensions
Dimensions EIA Standard 19” ackmount, 1.75” high, 8 “ deep
Operating Temperature ange
Operating Temperature angeOperating Temperature ange
Operating Temperature ange 0…70°C

Page 12 K8 ackmount Family User Manual
K8-AO8 Product Manual Section
Rear Panel Description
RS 485
OUTPUT 8
OUTPUT 7OUTPUT 1 OUTPUT 2 OUTPUT 4OUTPUT 3 OUTPUT 5 OUTPUT 6
Wink
TERM
Sync
K8 LINKK8 INPUT
AC IN 100-240V AC, 50-60Hz
Max. Power Consumption 20Watts Made in Germany
K8
K8K8
K8-
--
-AO8 ear Panel
AO8 ear PanelAO8 ear Panel
AO8 ear Panel
Output 1
Output 1Output 1
Output 1-
--
-8
88
8 Balanced analogue audio line outputs.
S 485
S 485S 485
S 485 emote control connector for PC or external control system connection.
TE M
TE MTE M
TE M DIP switch is used to terminate the device when only one of the two output ports are
being used. The device is terminated when the switch is set to ON. All switches must
be set the same way, either to ON or OFF!
K8 Input
K8 InputK8 Input
K8 Input The K8 signal feed input to the device.
K8 Link
K8 LinkK8 Link
K8 Link A passive loop through connection of the K8 Input for connecting the next device in
the chain.
Sync LED
Sync LEDSync LED
Sync LED The Sync light glows when a K8 Input is connected and locked to the signal coming
from a K8 Input device.
Wink LED
Wink LEDWink LED
Wink LED Light blinks when turned on by remote control software. This light may be used to
confirm that a device is being remote controlled.
Front Panel Description
0
-20
+12
0
-20
+12
0
-20
+12
0
-20
+12
0
-20
+12
0
-20
+12
0
-20
+12
0
-20
+12
POWER
2 3 4 5 6 7 8OUTPUT 1
ANALOGUE LINE OUTPUT
K8 DIGITAL AUDIO DISTRIBUTION
K8- AO8
K8
K8K8
K8-
--
-AO8 Front Panel
AO8 Front PanelAO8 Front Panel
AO8 Front Panel
Power LED
Power LEDPower LED
Power LED The Power LED is illuminated when the device is plugged in and the rear power
switch is turned on.
Output LEDs
Output LEDsOutput LEDs
Output LEDs The red, yellow and green channel Output LEDs show the Output signal level for each
channel at the output XL connector downstream of the software level trim.
Overview
The K8-AO8 is a K8 output device for receiving 8 audio channels from the K8 bus and decoding them into 8
analogue outputs.

K8 ackmount Family User Manual Page 13
Routing Capabilities
As shipped from the factory, the K8-AO8 will place audio channels 1-8 on outputs 1-8.
The K8 bus contains 16 audio channels, in two groups of 8. The K8 terminal control protocol is capable of
configuring the K8-AO8 to select either the group of channels numbered 1-8 or the group of channels
numbered 9-16 for output. Channel 1 appears on output 1, channel 2 on output 2 and so forth. When
selecting the second group of channels, channel 9 appears on output 1, channel 10 appears on output 2
and so forth.
The first two outputs of the AO8 device can select any stereo pair within the group of channels being
received.
Stacking Output Devices
The K8 bus supports a maximum quantity of 254 devices. Output devices may be daisy chained until the
maximum cable length of 200 meters has been reached. Output devices are passively connected and do
not refresh the K8 audio signal. This architecture has the benefit that a failure of an output device will still
allow audio to pass to the next device in the chain. Daisy chaining devices introduces no delay in the audio
signal.
Termination Setting
All 4 termination switches must be set to “on” when the AO8 is the last device in the K8 chain.
K8 link port connected: Termination Off
K8 link port not connected: Termination On
Control and Monitoring
All devices on the K8 bus may be controlled and monitored through a single S-485 connection to the AI8
device. The protocol is openly published on www.klein-hummel.com for use by software engineers and
control system programmers. The pinout of the S-485 port is as follows:
PIN 1 Phantom Ground
PIN 2 Phantom Power
PIN 3 Data A (+)
PIN 4 Data B (-)
PIN 5 Signal Ground
PIN 6-9 Not Used
A limited amount of serial data tunnelling is available between the serial ports on any two devices in the
system. This is useful for passing control data to another system, such as a lighting controller or external
relay box located in the same equipment area as the K8 output box.
The phantom power is used to drive K8 accessories designed to attach to the local control connector, such
as a local volume control wall plate. Phantom power is switched off by default and must be activated
through the control protocol.
Output Level Settings
The AO8 is shipped from the factory to provide a +4 dBu nominal output level with a peak level of +22
dBu. By default, the same signal level fed into an analogue input AI8 will appear at an analogue output
AO8 at the same level.
The output level of an AO8 may be trimmed down to any lower value by using the K8 terminal control
protocol.
DB9 Female Control Connector

Page 14 K8 ackmount Family User Manual
Front Panel LEDs
Each input channel has 3 front panel LEDs to show channel level. The green LED illuminates at signal
present 32 dB below digital full scale. The yellow LED illuminates at nominal level 12 dB below digital full
scale. The red LED illuminates just before the onset of clipping. Brief illuminations of the red LED are
acceptable in normal operation.
The AO8 output meters show the analogue signal level after it has been attenuated by the output level
trims settable in software. This is an indication of the audio level at the analogue audio output connector
of the unit.
Compatible Accessories
K8
K8K8
K8-
--
-485
485485
485 USB to S-485 adaptor cable for using a PC to program K8 system devices.
K8
K8K8
K8-
--
-***
******
*** A variety of input and output signal types are available and always growing.

K8 ackmount Family User Manual Page 15
K8-AO8 Technical Specifications
Electrical
Frequency esponse
Frequency esponseFrequency esponse
Frequency esponse 20 Hz – 22 kHz
Signal to Noise atio
Signal to Noise atioSignal to Noise atio
Signal to Noise atio >100dB(A)
Input
InputInput
Input K8 digital audio bus, J-45
Output
OutputOutput
Output 8 x analogue audio out, XL male connectors
Output Level
Output LevelOutput Level
Output Level +22 dBu peak, software adjustable attenuation
Control
ControlControl
Control S-485, DB-9 female connector, open published protocol
38400 Baud, 8 Data, 1 Stop, No Parity
Optional USB adaptor etc.
Termination Switch
Termination SwitchTermination Switch
Termination Switch 4-position DIP
Digital Audio Format
Digital Audio FormatDigital Audio Format
Digital Audio Format 48 kHz sampling rate, 24 bit, proprietary
Latency
LatencyLatency
Latency ½ millisecond worst case, analogue in to analogue out
Power equirements
Power equirementsPower equirements
Power equirements 100 – 240 Volt, 50-60Hz
20 Watts
IEC power cord connector
Front Panel Indicators
Front Panel IndicatorsFront Panel Indicators
Front Panel Indicators Power
Signal present, signal nominal level, signal peak level
ear Panel Indicators
ear Panel Indicatorsear Panel Indicators
ear Panel Indicators Sync, wink
Mechanical
Weight
WeightWeight
Weight 7 lbs / 3.2 kg
Dimensions
DimensionsDimensions
Dimensions EIA Standard 19” ackmount, 1.75” high, 8“ deep
Operating Temperature ange
Operating Temperature angeOperating Temperature ange
Operating Temperature ange 0…70°C

Page 16 K8 ackmount Family User Manual
K8-AO2 Product Manual Section
Rear Panel Description
Max. Power Consumption 10Watts RS 485
AC IN: 100-240V AC, 50-60Hz
OUTPUT 1 OUTPUT 2
OUT 2
OUT 2
K8 LINK
K8 INPUT
TERM
S
W
Made in Germany
K8
K8K8
K8-
--
-AO2 ear Panel
AO2 ear PanelAO2 ear Panel
AO2 ear Panel
Output 1
Output 1Output 1
Output 1-
--
-2
22
2 Balanced analogue audio line outputs, unbalanced line outputs on CA cinch.
S 485
S 485S 485
S 485 emote control connector for PC or external control system connection.
TE M
TE MTE M
TE M DIP switch is used to terminate the device when only one of the two output ports are
being used. The device is terminated when the switch is set to ON. All switches must
be set the same way, either to ON or OFF!
K8 Input
K8 InputK8 Input
K8 Input The K8 signal feed input to the device.
K8 Link
K8 LinkK8 Link
K8 Link A passive loop through connection of the K8 Input for connecting the next device in
the chain.
Sync LED
Sync LEDSync LED
Sync LED The Sync light glows when a K8 Input is connected and locked to the signal coming
from a K8 Input device.
Win
WinWin
Wink LED
k LEDk LED
k LED Light blinks when turned on by remote control software. This light may be used to
confirm that a device is being remote controlled.
Front Panel Description
ANALOGUE LINE OUTPUT
K8 DIGITAL AUDIO DISTRIBUTION
0
-20
+12
0
-20
+12
POWER
2
OUTPUT 1
K8- AO2
K8
K8K8
K8-
--
-AO2 Front Panel
AO2 Front PanelAO2 Front Panel
AO2 Front Panel
Power LED
Power LEDPower LED
Power LED The Power LED is illuminated when the device is plugged in and the rear power
switch is turned on.
Output LEDs
Output LEDsOutput LEDs
Output LEDs The red, yellow and green channel Output LEDs show the Output signal level for each
channel at the output connector downstream of the software level trim.

K8 ackmount Family User Manual Page 17
Overview
The K8-AO2 is a K8 output device for receiving 2 audio channels from the K8 bus and decoding them into 2
analogue outputs.
Routing Capabilities
As shipped from the factory, the K8-AO2 will place audio channels 1,2 on outputs 1,2.
The two outputs of the AO2 device can select any stereo pair from the K8 bus. A stereo pair must be
adjacent channels and begin with an odd numbered channel. For example, channels 1 and 2, 3 and 4, 5
and 6 and so forth are all valid.
Stacking Output Devices
The K8 bus supports a maximum quantity of 254 devices. Output devices may be daisy chained until the
maximum cable length of 200 meters has been reached. Output devices are passively connected and do
not refresh the K8 audio signal. This architecture has the benefit that a failure of an output device will still
allow audio to pass to the next device in the chain. Daisy chaining devices introduces no delay in the audio
signal.
Termination Setting
All 4 termination switches must be set to “on” when the AO2 is the last device in the K8 chain.
K8 link port connected: Termination Off
K8 link port not connected: Termination On
Control and Monitoring
All devices on the K8 bus may be controlled and monitored through a single S-485 connection to the AI8
device. The protocol is openly published on www.klein-hummel.com for use by software engineers and
control system programmers. The pinout of the S-485 port is as follows:
PIN 1 Phantom Ground
PIN 2 Phantom Power
PIN 3 Data A (+)
PIN 4 Data B (-)
PIN 5 Signal Ground
PIN 6-9 Not Used
A limited amount of serial data tunnelling is available between the serial ports on any two devices in the
system. This is useful for passing control data to another system, such as a lighting controller or external
relay box located in the same equipment area as the K8 output box.
The phantom power is used to drive K8 accessories designed to attach to the local control connector, such
as a local volume control wall plate. Phantom power is switched off by default and must be activated
through the control protocol.
Output Level Settings
The AO2 is shipped from the factory to provide a +4 dBu nominal output level with a peak level of +22 dBu
on the XL and terminal block connectors. By default, the same signal level fed into an analogue input AI8
will appear at an analogue output AO2 at the same level.
The CA cinch connectors are factory set to provide a –10 dBV nominal output level.
DB9 Female Control Connector

Page 18 K8 ackmount Family User Manual
The output levels of an AO2 may be trimmed down to any lower value by using the K8 terminal control
protocol.
Front Panel LEDs
Each input channel has 3 front panel LEDs to show channel level. The green LED illuminates at signal
present 32 dB below digital full scale. The yellow LED illuminates at nominal level 12 dB below digital full
scale. The red LED illuminates just before the onset of clipping. Brief illuminations of the red LED are
acceptable in normal operation.
The AO2 output meters show the analogue signal level after it has been attenuated by the output level
trims settable in software. This is an indication of the audio level at the analogue audio output connector
of the unit.
Compatible Accessories
K8
K8K8
K8-
--
-485
485485
485 USB to S-485 adaptor cable for using a PC to program K8 system devices.
K8
K8K8
K8-
--
-***
******
*** A variety of input and output signal types are available and always growing.
K8
K8K8
K8-
--
- MK
MKMK
MK Half rack mounting kit, accepts up to two devices.
K8
K8K8
K8-
--
-FMK
FMKFMK
FMK Flange mounting kit for mounting the device under tables, etc.

K8 ackmount Family User Manual Page 19
K8-AO2 Technical Specifications
Electrical
Frequency espo
Frequency espoFrequency espo
Frequency esponse
nsense
nse 20 Hz – 22 kHz
Signal to Noise atio
Signal to Noise atioSignal to Noise atio
Signal to Noise atio >100dB(A)
Input
InputInput
Input K8 digital audio bus, J-45
Output
OutputOutput
Output 2 x analogue audio out, XL male connectors , CA cinch connectors and
removable terminal blocks in parallel
Output Level
Output LevelOutput Level
Output Level +22 dBu peak on XL and terminals, software adjustable attenuation
+10 dBu peak (nominal –10 dBV) on CA cinch connectors
Control
ControlControl
Control S-485, DB-9 female connector, open published protocol
38400 Baud, 8 Data, 1 Stop, No Parity
Optional USB adaptor etc.
Termination Switch
Termination SwitchTermination Switch
Termination Switch 4-position DIP
Digital A
Digital ADigital A
Digital Audio Format
udio Formatudio Format
udio Format 48 kHz sampling rate, 24 bit, proprietary
Latency
LatencyLatency
Latency ½ millisecond worst case, analogue in to analogue out
Power equirements
Power equirementsPower equirements
Power equirements 95 - 240 Volts AC (±10%), 50 - 60 Hz, wide range power supply
10 Watts
IEC power cord connector
Front Panel Indicators
Front Panel IndicatorsFront Panel Indicators
Front Panel Indicators Power
Signal present, signal nominal level, signal peak level
ear Panel Indicators
ear Panel Indicatorsear Panel Indicators
ear Panel Indicators Sync, wink
Mechanical
Weight
WeightWeight
Weight 4.4 lbs / 2 kg
Dimensions
DimensionsDimensions
Dimensions 9.5” wide , 1.75” high, 8“ deep
Operating Temperature ange
Operating Temperature angeOperating Temperature ange
Operating Temperature ange 0…70°C (32…160°F)

Page 20 K8 ackmount Family User Manual
K8-ESB Product Manual Section
Rear Panel Description
Max. Power Consumption 20Watts RS 485
AC IN: 100-240V AC, 50-60Hz
CONFIG
S
W
Made in Germany
21 K8 OUT
EtherSound Network
IN OUT
Link
Activity
K8
K8K8
K8-
--
-ESB ear Panel
ESB ear PanelESB ear Panel
ESB ear Panel
S 485
S 485S 485
S 485 emote control connector for PC or external control system connection.
CONFIG
CONFIGCONFIG
CONFIG The first three DIP switch positions are used to terminate the device when only one
of the two output ports are being used. The device is terminated when the switch is
set to ON. Switches 1,2, 3 must be set the same way, either to ON or OFF!
The 4
th
DIP switch selects between 8 and 16 channel mode. ON is 8 channels. OFF is
16 channels.
K8 OUT
K8 OUT K8 OUT
K8 OUT 1 and 2
1 and 21 and 2
1 and 2 K8 digital audio bus outputs. Each one contains the same audio and control data and
each one is capable of driving a 200 meter line. When only one output is used the
termination switch must be set to ON.
Sync LED
Sync LEDSync LED
Sync LED The Sync light glows when an EtherSound network is connected and locked.
Wink LED
Wink LEDWink LED
Wink LED Light blinks when turned on by remote control software. This light may be used to
confirm that a device is being remote controlled.
EtherSound IN
EtherSound INEtherSound IN
EtherSound IN Used to connect to an upstream device of an EtherSound network according the
EtherSound standards.
EtherSound OUT
EtherSound OUTEtherSound OUT
EtherSound OUT Used to connect to a downstream device of an EtherSound network according the
EtherSound standards.
EtherSound Link LED
EtherSound Link LEDEtherSound Link LED
EtherSound Link LED Indicates that a valid EtherSound device is connected to the K8-ESB and is
synchronized.
EtherSound Activity
EtherSound ActivityEtherSound Activity
EtherSound Activity Indicates communication activity to the connected EtherSound device.
LED
LEDLED
LED
Front Panel Description
ETHERSOUND BREAKOUT
K8 DIGITAL AUDIO DISTRIBUTION
POWER
K8- ESB
K8
K8K8
K8-
--
-ESB Front Panel
ESB Front PanelESB Front Panel
ESB Front Panel
Power LED
Power LEDPower LED
Power LED The Power LED is illuminated when the device is plugged in and the rear power
switch is turned on.