Kramer PA-225NET User manual

KRAMER ELECTRONICS LTD.
PRELIMINARY
USER MANUAL
MODEL:
PA-225NET
Power Amplifier
P/N: 2900-300408 Rev 1

PA-225NET – Contents
i
Contents
1Introduction 1
2Getting Started 2
2.1 Achieving the Best Performance 2
2.2 Safety Instructions 3
3Overview 4
4Defining the PA-225NET Power Amplifier 5
5Connecting the PA-225NET 6
5.1 Connecting the PA-225NET 6
5.2 Wiring the Inputs 7
5.3 Connecting the Remote Controls 9
5.4 Connecting Speakers 10
6Operating the PA-225NET 11
6.1 Indicators 11
6.2 Setting the Priority Switch 11
7Troubleshooting 12
8Technical Specifications 13
Figures
Figure 1: PA-225NET Power Amplifier Rear Panel 5
Figure 2: Connecting the PA-225NET Power Amplifier 6
Figure 3: Connecting a Balanced XLR Input 8
Figure 4: Connecting a Balanced 6.5mm Phone Jack 8
Figure 5: Connecting an unbalanced RCA Input 8
Figure 6: Connecting an unbalanced 6.5mm Phone Jack 9
Figure 7: Connecting the Remote Volume Control 9
Figure 8: Connecting Galil 6-C Speakers to the PA-225NET 10

PA-225NET - Introduction
1
1 Introduction
Welcome to Kramer Electronics! Since 1981, Kramer Electronics has been
providing a world of unique, creative, and affordable solutions to the vast range of
problems that confront the video, audio, presentation, and broadcasting
professional on a daily basis. In recent years, we have redesigned and upgraded
most of our line, making the best even better!
Our 1,000-plus different models now appear in 14 groups that are clearly defined
by function: GROUP 1: Distribution Amplifiers; GROUP 2: Switchers and Matrix
Switchers; GROUP 3: Control Systems; GROUP 4: Format/Standards Converters;
GROUP 5: Range Extenders and Repeaters; GROUP 6: Specialty AV Products;
GROUP 7: Scan Converters and Scalers; GROUP 8: Cables and Connectors;
GROUP 9: Room Connectivity; GROUP 10: Accessories and Rack Adapters and
GROUP 11: Sierra Video Products; GROUP 12: Digital Signage; and GROUP 13:
Audio, and GROUP 14: Collaboration.
Congratulations on purchasing your Kramer PA-225NET Power Amplifier, which is
ideal for the following typical applications:
Dante™ network applications
Presentation rooms and multimedia applications for local audio amplification
Personal audio listening (for example, a PC and portable CD player)

2
PA-225NET - Getting Started
2 Getting Started
We recommend that you:
Unpack the equipment carefully and save the original box and packaging
materials for possible future shipment
Review the contents of this user manual
Use Kramer high performance cables.
Use only the power adapter that is supplied with this machine
Go to http://www.kramerav.com/downloads/PA-225NET to check for up-to-
date user manuals, application programs, and to check if firmware
upgrades are available (where appropriate).
2.1 Achieving the Best Performance
To achieve the best performance:
Use only good quality connection cables (we recommend Kramer high-
performance cables) to avoid interference, deterioration in signal quality due
to poor matching, and elevated noise levels (often associated with low
quality cables)
Do not secure the cables in tight bundles or roll the slack into tight coils
Avoid interference from neighboring electrical appliances that may adversely
influence signal quality
Position your Kramer PA-225NET away from moisture, excessive sunlight
and dust
This equipment is to be used only inside a building. It may only be
connected to other equipment that is installed inside a building.
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PA-225NET - Getting Started
3
2.2 Safety Instructions
Caution:
There are no operator serviceable parts inside the unit
Warning:
Use only the Kramer Electronics power supply that is
provided with the unit
Warning:
Disconnect the power and unplug the unit from the wall
before installing
!

4
PA-225NET - Overview
3 Overview
The Kramer PA-225NET is a high performance, networked power amplifier that
accepts Dante a network and two balanced, mono audio inputs on 3-pin terminal
blocks and converts the signal into a differential stereo audio output for speakers
on a 4-pin terminal block.
The PA-225NET Power Amplifier features:
Dante and analog local inputs
2 x 25W into 8Ω
2 x 35W into 4Ω
A balanced line-level output
Independent volume control per input
Priority switching between the Dante and local inputs
The PA-225NET Power Amplifier is housed in a Kramer TOOLS enclosure.

PA-225NET - Defining the PA-225NET Power Amplifier
5
4 Defining the PA-225NET Power Amplifier
Figure 1 defines the rear panel of the PA-225NET Power Amplifier.
Figure 1: PA-225NET Power Amplifier Rear Panel
#
Feature
Function
1
PRIORITY
Switch
NET
Priority is given to the Dante network signal, (see Section 6.2)
LOCAL
Priority is given to the Local input
2
Dante RJ-45 Ethernet Connector
Connect to the Dante audio source via the LAN
3
LEVEL
Trimmers
2
Turn clockwise to increase the amplitude of the second input
signal; turn anticlockwise to decrease the level
4
1
Turn clockwise to increase the amplitude of the first input
signal; turn anticlockwise to decrease the level
5
REMOTE 4-pin Terminal Block
Connect to the remote, 10kΩ volume control, (for example, the
W-LM) and mute-switch, (see Section 5.3)
6
ON LED
Lights blue when the device receives power
7
SIGNAL LED
Lights green when there is an input signal present
8
CLIP 1 LED
Lights red when the signal clips on the first input signal
9
CLIP 2 LED
Lights red when the signal clips on the second input signal
10
POWER 2-pin Terminal Block
Connect to the 48V power supply provided
11
2 LOCAL
IN1 Input
3-pin Terminal
Block
Connect to a line-level, balanced, stereo audio source, (for
example, a media player), see Section 5.2.1
12
3-pin Terminal
Block
Connect to a line-level, balanced, stereo audio source
13
2 LINE
OUT 1
Output
3-pin Terminal
Block
Connect to an unbalanced, stereo audio acceptor, (for
example, amplified speakers)
14
SPEAKER
22-pin Terminal
Block
Connect to the output 2 4Ω or 8Ω speaker
15
12-pin Terminal
Block
Connect to the output 1 4Ω or 8Ω speaker

6
PA-225NET - Connecting the PA-225NET
5 Connecting the PA-225NET
This chapter comprises the following sections:
Connecting the PA-225NET (see Section 5.1)
Wiring the inputs (see Section 5.2)
Connecting the remote controls (see Section 5.3)
5.1 Connecting the PA-225NET
Always switch off the power to each device before connecting it to your
PA-225NET. After connecting your PA-225NET, connect its power and
then switch on the power to each device.
Figure 2: Connecting the PA-225NET Power Amplifier
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PA-225NET - Connecting the PA-225NET
7
To connect the PA-225NET as illustrated in the example in Figure 2:
1. Connect a balanced, stereo audio source, (for example, a multimedia player)
to the 6-pin Local In terminal block, (see Section 5.2).
2. Connect a Dante network audio source to the Dante RJ-45 connector.
3. Set the Priority slide-switch to the required position, (see Section 6.2).
4. Connect the 3-pin Line Out 1 terminal block to the audio acceptor, (for
example, a recording device).
5. Connect a remote volume control, (for example, the W-LM) to the Remote
4-pin terminal block, (pins +V, LEVEL, and GND).
6. Connect a remote, momentary mute-switch to the Remote 4-pin terminal
block, (pins Mute and GND).
7. Connect the speakers to the Speaker 4-pin terminal block.
8. Connect the power adapter to the PA-225NET and plug the power adapter
into the mains power supply.
5.2 Wiring the Inputs
Your PA-225NET is provided with a 3-pin terminal block for its input connection.
This connector can accept either a balanced or an unbalanced connection,
however some modifications must be made for an unbalanced connection.
5.2.1 Wiring Balanced Inputs
When using a balanced input source and connector, you must ensure that the hot,
cold, and ground pins of the connector are matched up to the +, –, and ground
pins of the PA-225NET terminal block connector respectively. The following
diagrams illustrate how to connect standard XLR and TRS connectors.

8
PA-225NET - Connecting the PA-225NET
Figure 3: Connecting a Balanced XLR Input
Figure 4: Connecting a Balanced 6.5mm Phone Jack
5.2.2 Wiring Unbalanced Inputs
When using an unbalanced input source, a jumper must be added between the
negative (–) and ground terminals. The unbalanced source is connected to the
positive (+) and ground terminals.
Note: A jumper is required for connecting an unbalanced input.
Figure 5: Connecting an unbalanced RCA Input

PA-225NET - Connecting the PA-225NET
9
Figure 6: Connecting an unbalanced 6.5mm Phone Jack
5.3 Connecting the Remote Controls
The following diagram illustrates how to connect the W-LM Remote Volume
Control to the PA-225NET.
Note: The remote volume control overrides the level control on the rear of the
device.
Figure 7: Connecting the Remote Volume Control

10
PA-225NET - Connecting the PA-225NET
5.4 Connecting Speakers
The following table details the cable requirements for connecting the PA-225NET
to speakers.
Distance m (ft)
Wire Gauge (AWG)
Up to 7 (25)
16
7.5 to 12 (26 to 40)
14
12 to 18 (41 to 60)
12
The speakers must be connected to the PA-225NET as shown in Figure 8.
Figure 8: Connecting Galil 6-C Speakers to the PA-225NET

PA-225NET - Operating the PA-225NET
11
6 Operating the PA-225NET
6.1 Indicators
The following table details the LED indicators.
Label
Color
Description
SIGNAL
Green
There is an input signal present
ON
Blue
The device is receiving power
CLIP
Red
The input signal is being clipped
6.2 Setting the Priority Switch
The Priority switch determines which input takes priority in the event that there are
two live input signals. When the switch is set to NET, priority is given to the Dante
network signal; when the switch is set to Local, priority is given to the Local Input.
In the absence of a signal on the priority input, the secondary input is automatically
selected after about three seconds.

12
PA-225NET - Troubleshooting
7 Troubleshooting
The PWR LED does not light.
Check that the power adapter is plugged into a functioning outlet and that the
adapter is correctly connected to the PA-225NET.
No output is heard from the speakers; the CLIP LED lights.
Check that the level control and remote volume control are not turned down.
Check that the input and output connections are secure. Insure that the SIG LED
lights to denote a signal. If there is no signal detected, check the signal source and
that the level controls are set high enough.
Amplifier overheats and/or shuts down.
Check the CLIP LED on the rear of the amplifier to see if the signal is overdriving
(the signal light flashes red frequently). Overdriving the amplifier for extended
periods can cause a thermal shutdown.
Output sound is distorted or cracking.
Check all cables for damage or loose connections and reduce the gain on the
input signal at the mixer or preamp level. Replace the cables and speakers
temporarily to see if this resolves the problem.

PA-225NET - Technical Specifications
13
8 Technical Specifications
INPUTS:
2 Balanced stereo +4dBu/10kΩ on a 6-pin removable
terminal block
OUTPUTS:
2 Line-level outputs on a 3-pin terminal block
2 Mono speaker outputs on a 4-pin removable terminal
block
INPUT SENSITIVITY:
0.5V (–3dBV)
OUTPUT POWER:
2 x 35W @ 4Ω
2 x 25W @ 8Ω
AMPLIFIER TYPE:
Class D
MAXIMUM VOLTAGE
GAIN:
28X (26.5dB)
INPUT IMPEDANCE:
20kΩ (balanced)
10kΩ (unbalanced)
FREQUENCY RESPONSE
(–3dB):
30Hz to 20kHz
BANDWIDTH (-3dB):
30Hz to 30kHz
S/N RATIO:
>100dB
AUDIO THD + NOISE:
<0.1%
SLEW RATE:
30V/ms
CONTROLS:
2 Screw trimmers for line input sensitivity; remote 10kΩ
volume control; contact-closure control for mute
EXTERNAL MUTE:
5-12V DC
LED INDICATORS:
Power, Signal present, Clip 1, and Clip 2
POWER CONSUMPTION:
Standby 3.3W; Idle current draw 6.9W; 1/8 current draw
14.2W
DIMENSIONS:
15.6cm x 11.2cm x 6.8cm (6.14" x 4.41" x 2.68") W, D, H
WEIGHT:
0.28 kg (0.62lbs) approx.
SHIPPING WEIGHT:
0.9 kg (1.98lbs) approx.
INCLUDED
ACCESSORIES:
Power adapter
Specifications are subject to change without notice at http://www.kramerelectronics.com

For the latest information on our products and a list of Kramer distributors, visit
our Web site where updates to this user manual may be found.
We welcome your questions, comments, and feedback.
Web site: www.kramerelectronics.com
E-mail: [e-mail]
SAFETY WARNING
Disconnect the unit from the power
supply before opening and servicing
P/N:
2900-300408
Rev:
1
!