Mass-Kobo 404 A User manual

model404 A/S
Full Balanced Portable Headphone Amplifier
User’s Manual
HOW TO USE
<Battery Loading>
Slide open the latter half of the body and load 6 (six) AAA batteries.
Please set the polarity of the batteries right carefully.
The circuit in the amplifier may be broken by the wrongly placed batteries.
<Battery Replacing>
Please replace the batteries with new ones when the Power Indicator turns red.
Though you may use the amplifier for a while after the indicator turns red, replacing batteries
immediately is recommended.
The Power Indicator will turn red as the voltage goes down below 6.5V.
<Power by USB>
You can use the amplifier by the power provided by USB.
Use any USB charger or mobile battery that can provide more than 1A.
Use thicker USB cables; the voltage may be not enough with thinner cables.
The Power Indicator will turn red as the voltage goes down below 4.6V in this case.
R- L- R+ L+
For Line-in by the
Standard Balanced Plug
3.5mm
For the balanced
plug of AK series
2.5mm
R-R+L+L-
LR
G
1
23
4
L-
R+
R- L+
USB Charging Connector
Balanced Line-in
Balanced Headphone out
for Balanced Armature
Balanced
Headphone
out
Unbalanced
Headphone out Unbalanced
Line-in
Power
Indicator
Input Selector Volume Control
Power
Switch
made in Fujieda JAPAN
ON
POWER
UNBAL
BAL
INPUT
UNBAL INUNBAL HP
Headphone Amp. model４０４
BALANCE HP BAL-IEM BAL-IN EXT POWER

WARNINGS
1. Do not dismantle or break down the amplifier.
The amplifier may be broken, or you could be injured or even killed by the electricity.
2. Do not drop the amplifier, or hit it hard.
3. Do not use with the wrong batteries.
4. The amplifier may be broken by reversal effect caused by overdischarge, if you should try to use
rechargeable batteries to the last moments.
Please recharge or replace them immediately as the Power Indicator turns red.
5. Handle the plugs gently.
They may be broken if you should push or pull them forcibly.
6. Be careful to connect rightly with the input or output ports.
The music reproducing hardware connected with the output port may be broken by wrong
connections.
7. You will hear induction noise when you use the amplifier with the combination of balanced input
and unbalanced output.
Use the balanced output when you use the balanced input.
8. Do NOT connect headphones/earphones each with the balanced and unbalanced outputs at the
same time.
WARRANTY
1. We warrants this amplifier against defects in materials and workmanship under normal use for a
period of ONE (1) YEAR from the date of purchase. We will repair the defects at no charge.
Please send the User's Registration Card to us as soon as possible.
You would have to pay for the repair(s), if the card should not be sent beforehand.
2. We do not warrant against the damages caused by accident, abuse, misuse, flood, fire, earthquake
or other external causes, or by operating the amplifier outside the permitted or intended uses. We
may repair the amplifier damaged by them at the purchaser's cost.
3. We reserve our rights to refuse to repair the amplifier that lost the original form, or damaged too
much.

Specific
a
Model : F
u
Input : φ3.
Output : φ
φ
X
Maximum
Maximum
(
P
(
R
Maximum
1
6
Frequenc
y
Noise Lev
e
Power Su
p
External
P
Consumpt
i
Size : 113
m
Weight : 6
5
as of 2016
-
We reserv
e
MASS-Ko
b
1-1-36, Ch
a
Tel.: 81-54
-
Fax: 81-54
http://ww
w
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