Konan Labs KDA Series User manual

KDA Series Digital Power Amplifier
KDA2400/ KDA2600/ KDA2800
KDA4200/ KDA4300/ KDA4400
USER MANUAL
Thank you for purchasing this Class D audio amplifier. In order to
take full advantage of this product, please keep this manual and refer
to the operating instructions for detailed information.

2
Table of Contents
Key features ..............................2
Signal output connectors .....................6
2CH Panel ……........................3
Operating instructions .......................7
4CH Panel …..........................4
Maintenance .................…….8
Safety instructions …………………………..5
Troubleshooting .....................8
Precautionary measures and cautions ………..6
Specifications ....................9
Signal input connectors ........................6
Proper product disposal .................10
1. Key features
The KDA series is a very cost-effective, compact, easy-to-operate unit. Self-oscillating design type Class D
power amplifier with outstanding voice intelligibility, an excellent S/N ratio, clearly defined highs, a full mid
range and a powerful bass. It is ideal for DJs, audio studios, hotels, conference and multifunction rooms,
multi-media classrooms, etc.
The KDA series digital power amplifier design is upgraded from standard digital power amplifier, inherited
the high reliability and wide applicability. The form of digital modulation circuit is equipped, which allows the
tone quality to have a large dynamic range, high efficiency and low distortion. Bridge mode is also possible,
which allows the amplifier to have strong applicability. The power supply adopted the advanced SMPS circuit
design and APFC design, to provide a 100~240V universal applicable power supply with extremely high
efficiency. The APFC power supply provides a circuit power factor up to 0.99.
Years of dedication on digital amplifier, enable successfully to develop a new circuit topology: the more
complete digital signals are obtained after music signal adopting the new modulation mode. This new
modulation mode ensures sampling of some extremely small signals and enriches sampling modes. In addition,
the fixed switch frequency is greatly reduced, which allows the power amplifier to produce less heat and
greatly enhance the efficiency. At the same time, the static power consumption is also reduced by a wide
range.
The circuit protection has been carefully designed. As far as the short circuit problem is concerned, we solve
an insurmountable difficult problem in this field of the industrial, high frequency short circuit judgment.
Through a large number of experiments and improvements, we design a unique circuit to make the KDA series
power amplifier fully reliable. In addition, we dedicated on the study of power protection, current overloading
protection, over-voltage protection, under-voltage protection, temperature control, DC protection, peak
clipping, amplitude limiting, VHF protection and Automatic temperature control fan system.
Some characteristics of the KDA series digital amp:
* When the amp’s power plug has connected to the AC power, the amp will lit an orange LED, to indicate the
amp is power-connected.

3
* When switch on, the signal output has a smooth increase of the volume.
* When you want to test any protection function of the amp, please turn the amp to a big output, and test
the protection function. Then you can see the protection function very obviously.
* When the heat sink of the Power-supply reaches a temp of 80C degree, protection led will lit; When the
High-frequency transformer reaches a temp of 115C degree, the protection will lit; in case of protection
active, please turn off the amp, wait 30 seconds and restart. If the amp can not recover, please don’t try
to repair it and contact the manufacturer.
* Mute: the mute is recoverable.
When the amp is in short-circuit, DC fault, the mute will lit. (during the DC fault, the output will completely
cut, then gradually recover); When the heat sink of the amplification is overheated(reach 80C degree), the
amp will lower the output automatically; when the temperature reach 90C degree, the whole amp will stop
working in order to protect the amp. During overload, the mute will LED lit and have no output.
2. Front panel, Rear panel
KDA2400/ KDA2600/ KDA2800
(1) Status light: Clip indicator
(2) Status light: Signal indicator
(3) Status light: Power indicator
(4) CH1, 2 volume knob: To control the input volume of the amplifier
(5) Power switch: Power on/off
(6) Powercon: AC input for mains power supply
(7) Fan: The cold air intakes the amplifier from the front, cooling the internal heat sinks
(8) CH1, 2 output: Speakon connectors.
(9) CH1, 2 input and link: XLR(female/ male) connectors
(10) Sensitivity: 1.4V/ 1.0V/ 0.775V switch
(11) Working mode select: Stereo/ Parallel/ Bridge mode switch

4
3. Front panel, Rear panel
KDA4200/ KDA4300/ KDA4400
(1) Status light: Clip indicator
(2) Status light: Signal indicator
(3) Status light: Power indicator
(4) CH1, 2 volume knob: To control the input volume of the amplifier
(5) Power switch: Power on/off
(6) Powercon: AC input for mains power supply
(7) Fan: The cold air intakes the amplifier from the front, cooling the internal heat sinks
(8) CH1, 2, 3, 4 output: Speakon connectors.
(9) CH1, 2, 3, 4 input: XLR(male) connectors
(10) CH3, 4 Working mode select: Stereo/ Parallel/ Bridge mode switch
(11) CH1, 2 Working mode select: Stereo/ Parallel/ Bridge mode switch
4. Safety instructions

5
Caution: To reduce the risk of electric shock, do not remove the cover or rear panel. No user-serviceable parts
inside. Servicing must be carried out by qualified service personnel.
The lightning symbol in the triangle indicates insinuated components inside the housing with
hazardous voltages that can cause injury to persons.
The exclamation mark in the triangle indicates important operating and maintenance
(servicing) instructions that are provided in the documentation accompanying the unit.
* Caution: To reduce the risk of electric shock, do not remove the cover. No user-serviceable parts
inside.
* To avoid the risk of fire or electric shock, do not expose the unit to rain or moisture. Do not allow metal
objects or liquids to come into contact with the unit, since electric shock or malfunctions may result.
* Do not cover any ventilation slots, as this may result in overheating. Always install the unit in a
well-ventilated location. Ensure that the unit is not close to any heat source, and avoid dusty and moist
environments.
* Do not attempt to repair the unit yourself. Maintenance checks and repairs must be carried out only by
qualified personnel.
5. Precautionary measures and cautions
Ensure that the power switch is switched off before connecting the cables to install the unit.
Ensure that the mains power supply corresponds to the rated voltage of the unit.
Ensure that there is an adequate source of power; do not switch on several amplifiers at the same time.
Ensure that all connectors are correctly and securely connected.
Ensure that the input level (volume) controls are set to the lowest level (to the left) before the power is
switched on.
If the amplifier malfunctions, switch it off immediately. Do not attempt to repair it yourself; contact your
dealer for service.

6
Cautions for testing with sine wave/measuring the specifications :
When testing the parameters of the DA series amplifier with audio analyzer equipment like Audio Precision, an
electrical filter must be added between the output of the DA series amplifier & the audio analyzer. The
electrical filter is used to filter the ultra-high switching frequency. The switching frequency will affect the
precision of the testing results.
When testing the THD, S/N ratio and other parameters with sine wave signal, the output should be adjusted to
1/8 RMS output. This is the standard testing.
When using the oscilloscope to check the waveform of the DA series amplifier, some “hairs and shadow”
things will be seemed, but these “hairs and shadow” are not distortion. They are the switching frequency,
because the DA series is designed with self-oscillating type.
6. Signal input connectors
1) CHA & CHB Input & Link
Fig. 1 is input male XLR, one can use it to link to another amplifier
Pin1= Ground ; Pin 2= Signal + ; Pin 3= Signal -
Fig. 1
Attention: Improper connections will result in malfunctions. Ensure that connections are correct before
beginning operation.
7. Signal output connectors
Fig. 2: Signal output via Speakon connectors for Stereo mode
Channel A :
1+ Connect signal output to (+) speaker
1- Connect signal output to (-) speaker
2+ Do not used
2- Do not used
Channel B :
1+ Connect signal output to (+) speaker
1- Connect signal output to (-) speaker
2+ Do not used
2- Do not used

7
STEREO MODE
Fig. 2
Fig. 3: Signal output via Speakon connectors for Bridge mode
Channel A :
1+ Connect signal output to (+) speaker
1- Not connected
2+ Connect signal output to (-) speaker
2- Not connected
Channel B :
1+ Not connected
1- Not connected
2+ Not connected
2- Not connected BRIDGE MODE
Fig. 3

8
Attention: Improper connections will result in malfunctions. Ensure that the connections and operating mode
are correct before switching on the power.
8. Operating instructions
Operating procedures:
1）Connect the unit to appropriate speakers.
Get sure that the result of impedance of the speaker systems connected is not lower than 4 Ohms on
each channel when working in Stereo mode, 8 Ohms in Bridge mode.
2）Ensure that all input and output connections are correct and secure.
3）Ensure that the mains power supply corresponds to the rated voltage indicated on the amplifier.
4）Connect the signal source, e.g. mixing console, to the signal input of the amplifier.
5）Set the input level (volume) of the amplifier to the lowest setting.
6）First switch on the power for the signal source, e.g. mixing console, then switch on the power for the
amplifier.
7）Adjust the input level (volume) to the desired volume.
9. Maintenance
1. Clean the unit by wiping it with a slightly damp cloth. Do not permit moisture to enter the unit. Do not use
alcohol or any volatile liquid cleansers that may damage the unit.
2. Clean the ventilation slots regularly with a vacuum cleaner. This maximises cooling by the amplifier fans
and helps to prevent overheating.
10. Troubleshooting
In the event of operating problems, first check the causes described below before requesting assistance.
Problem
Possible causes
Suggested remedies
No response
when amplifier is
switched on
1. No power
1. Turn on the power.
2. Loose power cord connection
2. Ensure that the power cord is securely
connected to the mains supply before switching
on the amplifier power switch.
3. Blown fuse (Internal)
3. Turn off the power and check the internal
fuse. If the fuse has blown, always replace it
with the same type of fuse.
No sound
1. No input signal
1. Connect the signal source to the amplifier
input, then turn on the power.
2. Loose speaker connection or
malfunctioning speaker
2. Ensure that the speaker is securely
connected. Check to see that the speaker is in
good operating condition.

9
3. Incorrect connection
3. Ensure that the speaker is correctly
connected to the amplifier.
4. Overheating protection
4. Avoid overloading the amplifier for prolonged
periods. Do not attempt to operate the amplifier
in a poorly ventilated location. Check to see that
the cooling fans are operating properly and that
the ventilation slots are free of dust.
Inadequate
output volume
1. The signal input level (volume) is set
to the lowest level
1. Adjust the signal input level to the desired
volume.
2. Output of the signal source, e.g. CD
player, is too low
2. Increase the output of the signal source, or
adjust the input level of the amplifier.
11．Specifications

10