Cayin LA-34 User manual

Vacuum Tube Integrated Amplifier
LA-34
VACUUM TUBE INTEGRATED AMPLIFIER LA-34
VOLUME
MIN MAX
CD
AUX1
AUX2
SELECTOR
User's Manual
REV：1.1

Table of Contents
Thanks for choosing Cayin LA-34 Vacuum Tube Amplifier and please read the user's manual
carefully before installation and operation.
In order to prevent damage during transportation, the amplifier is packed with protective foams surrounding
the tubes. Before installation and operation, please remove these foams to avoid any risks.
Integrated
Table of Contents
How to Install Vacuum Tubes…………………………………………………………………………………………15
………………………………………………………………………………… 1
…………………………………………………………………………………………………………2
……………………………………………………………………………………………………………3
…………………………………………………………………………………………………………3
………………………………………………………………………………………………………………4
Maintenance…………………………………………………………………………………………………………………5
……………………………………………………………………………………………………………5
…………………………………………………………………………………………………………………6
…………………………………………………………………………………………………………………7
…………………………………………………………………………………………………………………8
……………………………………………………………………………………………………………………9
…………………………………………………………………………………………………………………10
………………………………………………………………………………………………………10
…………………………………………………………………………………………………………11
………………………………………………………………………………………………………12
…………………………………………………………………………………………………………………13
Small Tips …………………………………………………………………………………………………………………13
…………………………………………………………………………………………………………14
………………………
Package Contents
Product Features
Safety Precautions
Specifications
Warranty Service
Precautions
Front Panel
Rear Panel
Top Panel
Installation
Tube Replacement
Audio Connection
Speaker Connection
Turning on
Troubleshooting
1

Please carefully check the package first and then open it.
Package contents include:
1. Cayin LA-34 1 piece；
2. Main Fuse 2 pieces（100~120V T3.15A250V; 220~240V T2A250V)
3. Power cord 1 piece；
4. User's Manual 1 piece；
Please make sure local voltage level is matched with the input level of the amplifier,which indicates on the rear
panel. Too low or too high voltage may cause problem. Please contact our company or our local agent if you've
found improper voltage.
Recommendation:
Keep all packing materials for future use .
Cayin LA-34 Vacuum Tube Amplifier is designed and manufactured with our original parts and
reaching the best results. We are not responsible for problems and damages caused by non-original parts
replacement in the amplifier.
Integrated
NOTE:
2
Package Contents
All other parts except above are not included.
NOTE:

1. Unplug the power cord if you are not going to use the product for an extended period of time.
2. The machine will become hot after working for a long time. Please keep the unit's ventilation open and install
the amplifier at a well-ventilated place to avoid troubles and fire hazard.
3. Forbidden to operate when the output is open or shorted.
4. Do not attempt to service this product yourself. Opening the cover may expose you to dangerous voltage or
other hazards.
5. We are not responsible for any problems caused by checking and opening without permission of our
company. For service, Please contact a qualified service technician.
6. Do not place any objects filled with liquids such as vases or some others on the top or around.
7. Clean only with dry cloth.
8. Please move the amplifier carefully not to drop the unit or be subject to other strong shocks.
3
◆ Hand-made construction with the finest point-to-point wiring.
◆ Two EI output transformers with wide bandwidth are applied.
◆ Specially designed toroid transformer for power supply.
◆ 5BK7A tubes are used in the preamp stage.
◆ Four EL34 tubes are used for AB1 push-pull amplification.
◆ External user Bias Adjustment is accessible with BIAS TEST POINT.
◆ High-quality Japanese ALPS potentiometer.
◆ Equipped with easily-installed tube cover for protection.
Product Features
Safety precautions

4
Power Output
Frequency Response
THD
S/N Ratio
Input Sensitivity
Input Impedance
Output Impedance
Max Power Consumption
Tube
W D H
Net Weight
Working Condition
Storage Condition
× ×
32W+32W
10Hz～42kHz(-3dB)
1% (1kHz)
9dB
260mV
100kΩ
4Ω，8Ω
5BK7A×3、EL34 4
Temperature °C °C Moisture
Temperature °C °C Moisture
8
260W
330×272×180mm³
13.5kg
0 40 20% 80%
-20 70 20% 90%
×
~ ~
~ ~
Specifications
◆ To reduce the risk of electric shock, do not remove the cover.
◆ No user serviceable parts inside. Refer servicing to qualified
service personnel.
◆ To reduce the risk of fire or electronic shock, do not expose
the unit to rain or moisture.
The lightning flash with arrowhead symbol is intended to alert user to the presence of uninsulated
“dangerous voltage” within the product's enclosure that may be of a risk shock to persons.
The exclamation point is intended to alert user to the presence of important operation and maintenance
(servicing) instructions accompanying the appliance.
RISK OF ELECTRIC SHOCK
CAUTION
DO NOT OPEN

Warranty Service
1.This product is warranted for a period of twelve months beginning from the date of purchase.
2.The defective product must be returned to your dealer or our company for repairing when your dealer or our
company accepts your requirement.
3.The warranty doesn't extend to any product that has been opened by you without permission of our company.
NOTE:
◆
◆
Use the soft dry cloth to clean up the chassis regularly.
Do not use any chemicals for cleaning.
Maintenance
5
The information in this manual is subject to change
without further notice.
NOTE:
VACUUM TUBE INTEGRATED AMPLIFIER LA-34
VOLUME
MIN MAX
CD
AUX1
AUX2
SELECTOR

Precautions
YALIDA YN-401
◆ Connect the power only after finishing other connections.
◆
◆
◆
It is normal that power transformer becomes hot for extended period of operation.
Unplug the power cord if you're not going to use the product for an extended period of time.
Please make sure corresponding voltage is the same as required. We are not responsible for damage caused
by misuse of unsuitable voltage.
6
Connection of power cord:
Connect the speaker cables and signal cable first and then insert the power cord into the power socket.
Connected to AC Input
NOTE:
Connected to the power socket
T2.5AL250V
SPEAKER OUTPUTRIGHT SPEAKER OUTPUTLEFT
48 4 8 260
RISK OF ELECTRIC SHOCK
CAUTION
DO NOT OPEN
ZHUHAI SPARK ELECTRONIC EQUIPMENT CO., LTD. LA-34
CD AUX1AUX2
INPUT

7
Front Panel
1. Power Switch
Used to switch on/off the amplifier.
2.Volume Knob
Used to control volume
3. Power indicator
When starting up, the indicator light.
4. Input Selector
Used to choose 3 types of audio sources.
You can hear sound from CD when CD indicator is on.
You can hear sound from AUX1 when AUX1 indicator is on.
You can hear sound from AUX2 when AUX2 indicator is on.
234 1
VACUUM TUBE INTEGRATED AMPLIFIER LA-34
VOLUME
MIN MAX
CD
AUX1
AUX2
SELECTOR
POWER
ON
OFF

8
Rear Panel
1. Signal Input Terminal
Used for audio source input.
2. Right Channel Output
Used to connect with the right channel of speaker.
3. Left Channel Output
Used to connect with the left channel of speaker.
4. Power Socket with Main Fuse
Main fuse is located just below the power socket.
Replace the fuse with the same type as indicated.
134
2
T2.5AL250V
SPEAKER OUTPUTRIGHT SPEAKER OUTPUTLEFT
48 4 8 260
RISK OF ELECTRIC SHOCK
CAUTION
DO NOT OPEN
ZHUHAI SPARK ELECTRONIC EQUIPMENT CO., LTD. LA-34
CD AUX1AUX2
INPUT

Top Panel
9
②
③A1、A2、A3、A4:EL34
④V1、V2、V3:5BK7A
①Bias Test Point for testing the bias of the
Channel Power Tube(A1、A2、A3、A4）
Bias Adjustment Knob for Channel Power
Tube(A1、A2、A3、A4)
◆ Be careful of the high temperature of the tubes during operation.
◆ Replace the tubes carefully and correctly.
◆ Power tubes must be matched for well function.
NOTE
EL34 Current Testing
When you’re sure the connections are right, turn it
on by pushing the power button, then the indication
lamp will light up, then wait for about 10 minutes.
Connect the test lead of DC. V meter (or multi-
meter) to the (V1) terminal. Adjust the (V1) Bias Pot
t o m e a s u r e t h e D C . V o l t a g e a r o u n d
0.3V~0.35V(that means the static current is around
30mA~35mA for V1), and do the same procedure for
(V2)(V3)(V4).
Testing the current after using the machine for
about 150 hours can obtain the best state.
3 34
2
1
2
1
A1
A2
A3
A4
V2 5BK7A
BIAS TEST POINT
BIAS ADJ.
A2
A1
+
+-
V V
BIAS ADJ.
A3
A4
POWER TRANSFORMEROUTPUT TRANSFORMER
WIDE FREQUENCY RESPONSE
BIAS TEST POINT
+
+-
V V
OUTPUT TRANSFORMER
WIDE FREQUENCY RESPONSE
Tube Replacement Method:
After turning off the amplifier for about 20
minutes, hold the base of the tube and pull it
out vertically. By replacing different tubes,
you can enjoy different representations of
timbre.
V3 5BK7A
V1 5BK7A