KENWOOD KAC-8401 4 Channel Power Amplifier Instruction Manual
- June 17, 2024
- KENWOOD
Table of Contents
KAC-8401
KAC-8401 4 Channel Power Amplifier
Take the time to read through this instruction manual.
Familiarity with installation and operation procedures will help you obtain
the best performance from your new power amplifier.
For your records
Record the serial number, found on the back of the unit, in the spaces
designated on the warranty card, and in the space provided below.
Refer to the model and serial numbers whenever you call upon your KENWOOD
dealer for information or service on the product.
Model KAC-8401 Serial number
Safety precautions
WARNING
To prevent injury or fire, take the following precautions:
- When extending the ignition, battery, or ground wires, make sure to use automotive- grade wires or other wires with a 5 mm2 (AWG 10) or more to prevent wire deterioration and damage to the wire coating.
- To prevent a short circuit, never put or leave any metallic objects (such as coins or metal tools) inside the unit.
- If the unit starts to emit smoke or strange smells, turn off the power immediately and consult your Kenwood dealer.
- Do not touch the unit during use because the surface of the unit becomes hot and may cause burns if touched.
CAUTION
To prevent damage to the machine, take the following precautions:
- Be sure the unit is connected to a 12V DC power supply with a negative ground connection.
- Do not open the top or bottom covers of the unit.
- Do not install the unit in a spot exposed to direct sunlight or excessive heat or humidity.
- Also avoid places with too much dust or the possibility of water splashing.
- When replacing a fuse, only use a new one with the prescribed rating. Using a fuse with the wrong rating may cause your unit to malfunction.
- To prevent a short circuit when replacing a fuse, first disconnect the wiring harness.
NOTE
If you experience problems during If the unit does not seem to be working
right, installation, consult your Kenwood dealer. consult your Kenwood dealer.
FCC WARNING
This equipment may generate or use radio frequency energy. Changes or
modifications to this equipment may cause harmful interference unless the
modifications are expressly approved in the instruction manual.
The user could lose the authority to operate this equipment if an unauthorized
change or modification is made.
Installation
CAUTION
-
Do not install in the below locations;
(Unstable location, In a location that interferes with driving, In a location that gets wet, In a dusty location, In a place that gets hot, In a place that gets direct sunlight, In a location that gets hit by hot air) -
Do not install the unit under the carpet. Otherwise heat build-up occurs and the unit may be damaged.
-
Install this unit in a location which allows heat to easily dissipate.
-
Once installed, do not place any object on top of the unit.
The surface temperature of the amplifier will become hot during use. Install the amplifier in a place where people, resins, and other substances that are sensitive to heat will not come into contact with it.
This unit has cooling fans to decrease the internal temperature. Be careful not to block the cooling fan openings when installing the unit. Blocking these openings will inhibit the cooling of the internal temperature and result in malfunction. -
When making a hole under a seat, inside the trunk, or somewhere else in the vehicle, check that there is nothing hazardous on the opposite side such as a gasoline tank, brake pipe, or wiring harness, and be careful not to cause scratches or other damage.
-
Do not install near the dashboard, rear tray, or air bag safety parts.
The installation to the vehicle should securely fasten the unit to a place in which it will not obstruct driving. If the unit comes off due to a shock and hits a person or safety part, it may cause injury or an accident.
After installing the unit, check to make sure that electrical equipment such as the brake lamps, turn signal lamps and windshield wipers operate normally.
Controls/Indicator
This is a 4 channel amplifier including 2 stereo amplifiers in a body. One amplifier is referred to as amplifier A and the other is amplifier B. This unit is compatible with a large variety of systems by combining the switches and functions described in the following.
-
INPUT SENSITIVITY control
Set this control according to the pre-output level of the center unit connected with this unit, or to the maximum power output of the genuine- accessory car stereo.
The sensitivities of amplifiers A and B can be adjusted independently regardless of the position of the input selector switch.
Use the diagram on the right as a guide.
NOTE
For the pre-output level or the maximum power output, refer to the “Specifications” in the instruction manual of the center unit. -
Bch BASS BOOST switch
Setting this switch to “ON” emphasizes the bass.
You can use the BASS BOOST for amplifier B only.
ON position:
BASS BOOST is +6 dB.
OFF position:
BASS BOOST is OFF. -
FILTER switch
This switch allows to apply high-pass or low-pass filtering to the speaker outputs.
HPF (High-Pass Filter) position: The filter outputs the band of higher frequencies than the frequency set with the FILTER FREQUENCY control.
OFF position:
The entire bandwidth is output without filtering.
LPF (Low-Pass Filter) position:
The filter outputs the band of lower frequencies than the frequency set with the FILTER FREQUENCY control. -
OPERATION switch
The amplification methods of the signals input to amplifiers A and B can be selected independently according to the setting of this switch.
STEREO position:
The amplifier can be used as a stereo amplifier. -
MONO (Lch) position:
Amplifies the signal input from the left side only. Set to this position and make bridged connections to use as a high-power monaural amplifier. (The input right signal is not output.) -
INPUT SELECTOR switch
This switch selects the input method of the signals to be amplified by amplifiers A and
A B position:
Amplifies both of the signals input to amplifiers A and 6.
A position:
Amplifies only signal input amplifier A with both amplifiers A and 6.
-
FILTER FREQUENCY control
When the FILTER switch is set to the HPF (High-Pass Filter) or LPF (Low-Pass Filter) position, the threshold frequency can be adjusted with this control. -
Power indicator
When the power is turned on, the Power indicator lights.
If the Power indicator does not light when the power is turned on, the protection function may be activated. Check whether there is any indication of trouble.
The protection function is activated in the following situations:
This unit is equipped with a protection function for protecting this unit and
your speakers from various accidents or problems that can occur.
- When the protection function is triggered, the Power indicator goes off and the amplifier stops operating.
- When a speaker wire may be shortcircuited.
- When a speaker output contacts ground.
- When the unit malfunctions and a DC signal is sent to the speaker output.
- When the internal temperature is high and unit won’t operate.
- When a ground wire of the center unit (cassette receiver, CD receiver, etc.) or this unit is not connected to a metal part serving as an electrical ground passing electricity to the battery’s negative terminal.
Connection
8. Fuse (40 A)
If you can’t find the specified capacity fuse at your store etc., consult your
Kenwood dealer.
9. Battery terminal
10. Ground terminal
11. Power control terminal
Controls the unit ON/OFF.
NOTE
Controls the unit power. Be sure to connect it with all the systems.
12. Speaker output terminals
Stereo Connections:
When you wish to use the unit as a stereo amplifier, stereo connections are
used.
The speakers to be connected should have an impedance of 2sL or greater.
When multiple speakers are to be connected, ensure that the combined impedance
is 252 or greater for each channel.
Bridged Connections:
When you wish to use the unit as a high-output monaural amplifier, bridged
connections are used. (Make connections to the LEFT channel 0 and the RIGHT
channel 0 SPEAKER OUTPUT terminals.)
The speakers to be connected should have an impedance of 452 or greater.
When multiple speakers are to be connected, ensure that the combined impedance
is 4Q or greater.
CAUTION
The rated input of the speakers should be no less than the maximum output of
the amplifier. Otherwise malfunction may result.
RCA cable ground lead terminal When using an RCA cable with a ground lead
attached, connect the ground lead to this terminal.
LINE IN terminal
LINE OUT terminal
These jacks output respectively the signals input to amplifiers A and B. They
always output the stereo signals regardless of the position of the OPERATION
switch.
16. Speaker level input terminals
The genuine-accessory car stereo shall have a maximum power output of no more
than 40 W.
Do not connect the speaker output leads from a power amplifier (Optional) to
the speaker level input terminals of this unit, for this may cause malfunction
or damage.
Do not connect cables and leads to both RCA cable input jacks and the speaker
level input terminals simultaneously, for this may cause malfunction or
damage.
Connect the power control lead to a power supply which can be turned ON/OFF by
the ignition key switch (ACC line). With this connection, shock noise may be
generated when the power of the genuine-accessory car stereo is switched
ON/OFF.
Speaker Selection
The rated input power of the speakers that are going to be connected should be greater than the maximum output power (in Watts) of the amplifier. Use of speakers having input power ratings that are less than the output power of the amplifier will cause smoke to be emitted as well as damage.
The impedance of the speakers that are going to be connected should be 2Q or greater (for stereo connections), or 4Q or greater (for bridged connections). When more than one set of speakers are going to be used, calculate the combined impedance of the speakers and then connect suitable speakers to the amplifier.
RCA cable or Speaker level input connection
(RCA cable Connections)
(Speaker level input Connections)
Speaker wire connection
(Stereo Connections)
Power wire connection
System examples
4-channel system
2-channel system
Principle of Tri-mode
Method of frequency band division using a coil and capacitor.. . in case of
GdB/oct. slope
Example:
When it is required to set a crossover frequency of 120 Hz using speakers with
an impedance of 4 ohms.
Prepare commercially-available coil and capacitor with the closest ratings to
the results calculated from the formula above. The capacitor rating should be
as close as possible to 331.25 (pF) and the coil rating should be as close as
possible to 5.3 (mH).
CAUTION
*If you wish to bridge-connect a speaker, the speaker impedance must be no less than 4 ohms.
Connecting a speaker with an impedance lower than 4 ohms may damage the unit.
Be sure to connect capacitors to speakers to which high frequencies will be
passed. Failure to do so will result in a drop of the combined impedance with
the subwoofer.
Ensure that the withstand voltage and current ratings of the capacitors (C)
and coils (L) are sufficient.
Troubleshooting Guide
What might appear to be a malfunction in your unit may just be the result of slight misoperation or miswiring. Before calling service, first check the following table for possible problems.
| PROBLEM | POSSIBLE CAUSE | SOLUTION |
|---|
No sound.
(No sound from one side.) (Blown fuse.)| Input (or output) cables are
disconnected.
Protection circuit may be activated
Volume is too high.
The speaker cord is shorted..| Connect the input (or output) cables.
Check connections by referring
Replace the fuse and use lower After check the speaker cord and to
“Indicator”. volume.
fixing the cause of the short, replace the fuse.
The output level is too
small (or too large).| The input sensitivity adjusting
control is not set to the correct
position.| Adjust the control correctly referring to “Controls”.
The sound quality is bad.
(The sound is distorted.)| The speakers wire are
connected with wrong +/- polarity.
A speaker wire is pinched by a screw in the car body.
The switches may be set improperly.| Connect them properly checking the +/- of
the terminals and wires well.
Connect the speaker wire again so that it is not pinched by anything.
Set switches properly by referring to “System examples”.
Specifications
Specifications subject to change without notice.
Audio Section
Max Power Output ………………………………………………………….. 320 W x 2
Rated Power Output
Normal (4 Q} (20 Hz — 20 kHz, 0.08 % THD)…………………………………… 60 W x 4
(4 Q) (DIN : 45324 , +B = 14.4V) ……………………………….. 60Wx 4
(2 Q) (1 kHz, 0.8 % THD) …………………………………………………… 90Wx 4
Bridged (4 Q) (1 kHz, 0.8 % THD)……………………………………………….. 180 W x 2
Frequency Response (+0, —3 dB)…………………………………………….. 5 Hz — 50 kHz
Sensitivity (rated output) (MAX.) ………………………………………………… 0.2 V
(MIN.) ………………………………………………… 5.0 V
Signal to Noise Ratio…………………………………………………………………………… 100 dB
Input Impedance…………………………………………………………………… 10 kg2
Low Pass Filter Frequency (12 dB/oct.) ……………………… 50 — 200 Hz (variable)
High Pass Filter Frequency (12 dB/oct.)………………………. 50 — 200 Hz (variable)
Bass Boost Circuit (90 Hz) …………………………………………………………. OFF / +6 dB
General
Operating Voltage …………………………………….. 14.4 V (11 — 16 V allowable)
Current Consumption (4 Q, 10 % THD) ………………………………………… 39 A
Dimensions (W x H x D)………………………………………………….. 285 x 57 x 268 mm
11-1/4 x 2-1/4 x 10-9/16 inch
Weight …………………………………………………………………… 2.96 kg (6.5 Ibs)
This warranty will be honored only in the U.S.A.
KENWOOD LIMITED WARRANTY FOR CAR STEREO COMPONENTS
HOW LONG IS THE WARRANTY
Kenwood U.S.A. Corporation (“Kenwood”) warrants this product for a period of
one (1) year from the date of original purchase.
WHAT IS COVERED AND WHAT IS NOT COVERED
Except as specified below, this warranty covers ail defects in material and
workmanship in Kenwood car stereo components. The following are not covered by
the warranty:
-
Any product which is not distributed in the U.S.A. by Kenwood or which is not purchased in the U.S.A. from an authorized Kenwood car stereo dealer or an automobile dealer, unless the product is purchased through the USA Military Exchange Service.
Any product on which the serial number has been defaced, modified or removed. Damage, deterioration or malfunction resulting from: -
Any shipment of the product (claims must be presented to the carrier).
Installation or removal of the product.
Accident, acts of nature, misuse, abuse, neglect, unauthorized product modification or failure to follow instructions supplied with the product.
Repair or attempted repair by anyone not authorized by Kenwood.
Any other cause which does not relate to a product defect.
WHO IS PROTECTED
This warranty is enforceable only by the original purchaser.
WHAT WE WILL PAY FOR
We will pay for all labor and material expenses for covered items, Payment of
shipping charges is discussed in the next section of this warranty.
HOW TO OBTAIN WARRANTY SERVICE
If your KENWOOD product ever needs service:
- Take or ship it to any KENWOOD Authorized Service Center in the U.S.A. along with &complete description of the problem. (if you are uncertain as to whether a Service Center is authorized, please call 1-800-KENWOOD for the nearest Service Center. 1-800-536-9663).
- Although you must pay any shipping charges if it is necessary to ship the product for warranty service, we will pay the return shipping charges if the repairs are covered by the warranty within the United States.
- Whenever your units are taken or sent for warranty service, you must include a copy of the original dated sales receipt as proof of warranty coverage.
LIMITATION OF IMPLIED WARRANTIES
ALL IMPLIED WARRANTIES, INCLUDING WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE, ARE LIMITED IN DURATION TO THE LENGTH OF THIS
WARRANTY.
EXCLUSION OF DAMAGES
KENWOODS LIABILITY FOR ANY DEFECTIVE PRODUCT IS LIMITED TO THE REPAIR OR
REPLACEMENTOF THE PRODUCT AT OUR OPTION. KENWOOD SHALL NOT BE LIABLE FOR:
- INSTALLATION OR REMOVAL CHARGES, DAMAGE TO OTHER PROPERTY CAUSED BY ANY DEFECTS IN KENWOOD CAR STEREO COMPONENTS, DAMAGES BASED UPON INCONVENIENCE, LOSS OF USE OF THE PRODUCT; OR
- ANY OTHER DAMAGES, WHETHER INCIDENTAL, CONSEQUENTIAL OR OTHERWISE.
SOME STATES DO NOT ALLOW LIMITATIONS ON HOW LONG AN IMPLIED WARRANTY LASTS AND/OR DO NOT ALLOW THE EXCLUSION OR LIMITATION OF INCIDENTAL OR CONSEQUENTIAL DAMAGES, SO THE ABOVE LIMITATIONS AND EXCLUSIONS MAY NOT APPLY TO YOU.
This warranty gives you specific legal rights, and you may also have other rights which vary from state to state.
If a problem develops during or after the Limited Warranty Period, or if you have any questions regarding the Operation of the product, you should contact your KENWOOD Authorized Dealer or Authorized Service Center. If the problem or your question is not handled to your satisfaction, please contact our Customer Relations Department at the address listed below:
KENWOOD U.S.A. CORPORATION
P.0 Box 2274% 2201 East Dominguer Street, Long Beach CA 908016745
Tel: 1310) 639-5300
References
Read User Manual Online (PDF format)
Read User Manual Online (PDF format) >>