ALLNIC AUDIO A-2000 User manual

ALLNIC AUDIO
A-2000
KT120 STEREO POWER AMPLIFIER
OWNER’S MANUAL

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ALLNIC AUDIO
A-2000 KT120 STEREO POWER AMPLIFIER
Thank you for purchasing the Allnic Audio A-2000 KT120 Stereo Power
Amplifier. We are certain your trust in Allnic Audio and Allnic Audio USA, as
well as your appreciation for the sound of this high-quality device, will be
rewarded by its excellent operation for years to come.
Please read this entire manual before you connect the A-2000 KT120
Stereo Power Amplifier to the other components of your system and the
wall outlet.
Albert Porter
[email protected]
Dallas, TX
North American Distributor, Allnic Audio.
AllnicAudioUSA.com

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TABLE OF CONTENTS:
___________________________________________________________________
INTRODUCING THE A-2000 KT120 STEREO POWER AMPLIFIER 4
___________________________________________________________________
WHAT’S IN THE BOX? 5
___________________________________________________________________
SAFETY 5
___________________________________________________________________
CLEANING
Chassis
Connectors 5
___________________________________________________________________
INITIAL SET-UP
Location, Location, Location
Inputs
Speaker Terminals
Power Connection 5
___________________________________________________________________
INITIAL POWER ON 6
___________________________________________________________________
OPERATION 6
___________________________________________________________________
TUBES AND TUBE BIAS 7
___________________________________________________________________
SPECIFICATIONS 7
___________________________________________________________________
WARRANTY 8
___________________________________________________________________
FIGURES 8
Please read about SAFETY before you attempt to use the A-2000 - we care
about our customers and the equipment, and we want you to enjoy this
product for a long time!

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INTRODUCING THE A-2000 KT120 STEREO POWER
AMPLIFIER
The A-2000 stereo power amplifier is Allnic Audio’s only
KT120 stereo power amplifier model. Like all Allnic
Audio products, the A-2000 has Permalloy (iron and
nickel alloy) for its transformer cores. Allnic is grateful
to Mr. G.W. Elmen of Western Electric for inventing
Permalloy for transformer core use, and in so doing,
providing an enormous service to recorded music
listeners everywhere.
The A-2000 has the following features:
70 watts of high power output. The A-2000 is a push-pull,
triode/pentode switchable power amplifier.
Powerful Driving Circuitry. Allnic believes in the
importance of using high-quality, low noise and powerful
driving circuitry in all its amplifying devices. Therefore, in
the A-2000, we employ the E282F tube in triode mode as
the second stage driver tube, with a load of about 5K
ohms, and using 20mA of current. The listener can easily
hear and even "feel" the differences between this design
and other, more conventional, ones. Please imagine, as
you listen to the A-2000, its sound compared to the sound
of an amplifier with conventional 12AU7 or 12BH7's used
as drivers, with a load of about 47K ohm, and using 2 to
3mA of current.
“Full Engagement" Output Transformers. Conventional
output transformers use pre-set secondary windings to
accommodate 4, 8 and 16 ohm loudspeaker loads.
However, these conventional transformers utilize
only one secondary winding at a time, while the other
secondary windings remain "idle". This approach has
two adverse effects. First, the output transformers are
not working at their maximum efficiency, reducing their
output relative to their potential. Second, the "idle"
windings are not actually "idle"; they are subject to
parasitic oscillations, producing their own "signal". This
undesirable electrical information is additive to the
transformer's output, distorting the amplified signal
going to the loudspeaker. Allnic's "Full Engagement"
transformers address these issues by having 4
independent, secondary windings which are always fully
connected, never "idled". This means that all secondary
windings are always connected to your loudspeakers,
regardless of which output switch position you use (4 ohms
or 8 ohms or 8 ohms or 16 ohms, depending on the factory
configuration you have selected). The result is that there is
neither a loss of transformer output efficiency, nor the
introduction into the output signal of distortion from
parasitic oscillations of the secondary windings.
Large Nickel/FeSi Core Output Transformers. As with our
other models, Allnic uses very large output transformers (96
mm) with nickel, mixed with FeSi, cores. This provides for
higher inductance with fewer windings than other designs
can provide and results in the great benefit of an extremely
wide range of output frequencies.
"Soft-start" Circuitry. Allnic uses soft start circuitry that,
after sufficient warm-up only, provides the high voltage
supply to the plate of each tube. This protective design
results in prolonged tube life and fewer and less frequent
issues with tube performance.
Analogue Power Tube Current Monitors. In order to
provide constant current (bias) monitoring for the power
tubes, Allnic uses a separate analogue current meter for
each tube. The meters make it exceptionally easy to see
the status of each tube at any time and to respond
immediately to any variation in bias by use of the bias
control knob for the relevant tube. The meters offer a
simple, unambiguous indication of each tube's status
compared to conventional LED bias monitors.
"On-the-Fly" Triode/Pentode Switching. Switching between
triode and pentode operation can be done "on-the-fly" at
any time while the amplifier is in use.
Beautiful 10KHz square wave response. See Figures 1-3.
Fig.1 Square Wave 50Hz Fig.2 Square Wave 1KHz
Fig.3 Square Wave 10KHz
Measured by LEADER LAG-126 Audio Signal Generator and KENWOOD CS-4125
Oscilloscope.

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As are all Allnic Audio products, the A-2000 is fully
RoHS (EU Reduction of Hazardous Substances
regulation) compliant in construction and materials.
WHAT’S IN THE BOX?
Please check that the shipping box contains the
following:
One (1) Allnic A-2000 stereo power amplifier
One (1) IEC type power cord
One (1) Owner’s Manual
Note:
1) The A-2000 ships with the tubes installed.
2) The A-2000 will work with most IEC type
aftermarket power cords. Of course, only you
can determine the power cord that works most
synergistically with the A-2000 in your system.
3) Be sure the A-2000 is labeled for the AC voltage
of your location. If it is not, please contact
Allnic Audio USA.
We advise that you keep the box and other packing
materials that your A-2000 came in. It will be useful if
you sell your A-2000 or in the unlikely event you need
to ship it for service.
SAFETY
Remove ALL protective cushioning material
(cardboard around and “O” rings on tubes)
inside the tube chimneys before operation. The
tube chimneys should contain NOTHING except
the tubes.
Disconnect the power cord by pulling the plug,
not the cable.
Do not attempt any repairs. Do not remove the
unit’s chassis cover without specific
authorization from Allnic Audio USA.
Keep the power cord away from heat sources
Keep the unit away from liquids – do not allow
any liquid to enter the interior of the unit.
When the unit is moved from a cold to a warm
environment, allow sufficient time for any
condensation to evaporate before plugging the
A-2000 into an AC connection.
Do not attempt any repairs.
CLEANING
A. Chassis and glass
Use only a soft, lint-free cloth, dampened slightly with water
only (NO cleaning fluids!), to clean the faceplate, chassis and
tube chimneys of the A-2000.
B. Connectors
You may use any good quality contact cleaner recommended
for such applications to clean the contacts from time to time,
as you deem appropriate.
INITIAL SET-UP
A. LOCATION, LOCATION, LOCATION
Like all audio products using tubes, the Allnic Audio A-2000
needs to be placed on a solid stand in a location that provides
good air circulation around, above and below the monoblock.
DO NOT cover the top of the A-2000.
DO NOT place the unit on carpet or foam.
DO NOT subject the unit to knocks and shocks as you
move it around. This advice is meant particularly for
those who may want to place the A-2000 on some kind
of after-market isolation feet or similar devices.
Dropping one side of the A-2000, or the whole of the
unit, is not a good thing to do.
DO NOT place the unit near a strong light or heat source.
DO NOT place anything heavy on the unit.
DO NOT allow rubber or vinyl materials to rest on the
chassis for long periods of time. This could discolour the
metal.
DO place the unit on a shelf or stand that is stable and
not subject to vibration or sudden shock.
DO consider using a high quality power cord, inter-
connects and speaker cables. The A-2000 is a highly
sensitive piece of electronic designed for neutrality and
will output what you put into it.
DO try to place A-2000 away from major sources
and potential receivers of RFI and EMI. Though
well shielded, the A-2000 will function best away
from large power transformers and other sources
of such interference and from other equipment
that could be susceptible to/sources of such forms
of interference.

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B. INPUTS
There are two (2) pairs of female inputs. One pair accepts
balanced cables with male XLR connectors; the other accepts
cables with single-ended, RCA type male connectors. These
input connections are located on the right (facing the chassis
rear) rear of the chassis, with the balanced inputs closest to
the side edge. In each case, the left channel connections are
above those for the right channel. To the left of each XLR
input there is a switch to select one of two pin configurations
for a balanced cable (i.e., it changes the phase). The top
position is for pin 2” hot” and pin 3 “cold”; the bottom
position is for the reverse (in both cases, pin 1 is ground).
Please refer to Figure 4
C. SPEAKER TERMINALS
The A-2000 is equipped with high-quality speaker terminals
for each channel. These terminals are located on the left side
of the rear panel of the A-2000 chassis (facing the chassis
rear), with the right speaker connections closest to the left
side of the chassis. The terminals for the live connections,
marked positive “+” are on the top, and the return
connections labeled negative “-”, underneath. Between the
left and right pairs of terminals is a switch that provides for
either 8 or 4 ohm impedance, as your speakers may require.
The upper position of the switch is for 8 ohm operation; the
lower for 4 ohm operation. 8 and 16 ohm terminals are
available by special order. The terminals accept bare wire
(not recommended) and spade and banana type connectors.
Please refer to Figure 4.
D. POWER CONNECTION
Connect the input interconnect and speaker cables
before you insert the power cable into the receptacle in
the centre (facing the back) rear of the chassis. The A-
2000 uses a standard three prong male IEC connection
for AC input. You need to use a power cord with a
female three prong IEC connector at one end. Please
refer to Figure 4.
The A-2000 you have purchased is set internally for AC
110/120 volt – 60 HZ operation. There is no way to
change this to another AC setting without return of the
unit to the factory for re-wiring, at the owner’s cost,
including transport both directions.
INITIAL POWER-ON
Once you have your A-2000 in place and all connections have
been made to your source(s) and preamplifier, you are ready to
turn on the power for your A-2000. Before you power up
the A-2000, though, be sure you have:
removed ALL the cushion materials (cardboard around and
“O” rings on tubes) from inside the tube chimneys
selected the input connection that you want to use, single
ended (RCA) or balanced (XLR); and if you are using the XLR
connectors, set the switch beside them to the appropriate
pin configuration.
turned on your source(s) and your preamplifier, and turned
the preamplifier’s volume control down to zero or otherwise
muted its output
securely and correctly fastened the speaker cables and
ensured that they are also connected properly to the
speakers
checked that all power tubes are snug in their sockets
Turn on the A-2000 by pushing in the power switch button
located at the right of the front panel (facing the front of the
unit to the “on” position (See Figure 5. The “on” position is
with the button switch depressed. Of course, the off position is
the reverse. After about a thirty to forty (30 - 40 second delay
(the soft start, the A-2000 will be powered on.
OPERATION
When the power is on, the current meters on the top plate of
the chassis will illuminate. From this point on, operation is
straight-forward. When you are finished listening, turn off your
A-2000(s monoblock(s first; then, turn off your preamplifier
and sources. If the A-2000’s are in triode mode at turn-off, they
will produce a sound through the speakers as the amplifier’s
relays turn off. Though this sound is harmless to speakers,
some users may prefer not to hear it. To avoid the sound,
simply switch the A-2000’s to pentode mode prior to turning
them off (see the “On-the-Fly Triode/Pentode Switching
section below).
In the case of any failure, please contact Allnic Audio USA for
assistance.
“ON-THE-FLY” TRIODE/PENTODE SWITCHING
You can use the Triode/Pentode “Mode Selector” button at any
time during operation to switch back and forth from Triode to

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Pentode operation. Press the mode selector button down to
have the A-2000 operate in Triode mode; press the button
again so it is in the raised position to have the A-2000 operate
in Pentode mode (See Figure 5.
THE CURRENT METERS
The two illuminated meters indicate the current supplies to
the four KT120 power tubes in the A-2000. Between and to
the outside of each channel pair of KT-120’s is a small toggle
switch. Pushing the toggle toward the rear of the chassis
allows you to read and use the meter to bias the rear KT120;
pushing the toggle toward the front switches the meter to
the front KT-120. You can use the toggle during operation.
There is a potentiometer for each KT120 (Refer to Figure 6.
When you turn on the A-2000, the needle of the current
meter for each KT120 should be between the two parallel
lines on the meter face. Any error of current supply to or
failure of a KT120 tube is indicated by the needle on the
meter moving out from between these two parallel lines.
If a meter’s needle drops to the left limit of the meter’s face
during operation, this indicates a failure of the related KT120
tube. You must turn off the A-2000 and replace both the fuse
(0.5A, 250V, 20mm glass type for that tube and the KT120.
To replace a fuse, unplug the A-2000; then, using a
screwdriver, simply turn the top of the fuse cap counter
clockwise. It will spring out holding the fuse. Replace the fuse
in the fuse cap, push the fuse cap down and turn it so it locks.
If you have any questions about doing this, please contact
Allnic Audio USA for assistance.
TUBES AND TUBE BIAS
Each A-2000 uses the following tubes:
Four (4) x KT120
Four (4) E282F
Two (2) x 6AK6
Because of the individual bias for each KT120, it is not
necessary to use a matched quad of these power tubes in the
A-2000.
If the needle of a current meter for a KT120 has moved to the
left of the parallel lines on the meter face, using an
appropriately bladed screwdriver, adjust the potentiometer
directly in front of that tube’s location by turning it clockwise
until the needle has returned to between the meter’s parallel
lines. If the meter needle has moved to the right of the
parallel lines on the meter face, turn the potentiometer control
counter-clockwise to correct.
You may use any KT120 type tube in the A-2000. Of course,
you will have to adjust the bias back into the area between the
two parallel lines of the meter for a tube when it is replaced.
Please refer to Figure 6 for tube locations. CAUTION: If you
intend to change KT120’s, ensure that you use the
potentiometers to trim back the bias below (to the left of)
the parallel lines on the meters first. This will prevent the new
pair of KT120’s from drawing too much current at first turn-on
(not an uncommon characteristic and tripping the power fuse
at the IEC connection. No harm is done to the original tubes by
turning the bias down, nor is any harm done to the new tubes
by having them biased low to start. Once the new tubes are
installed and the A-2000 is on, use the potentiometers to
adjust the bias so the needles for each meter are again
between the two parallel lines on the meter.
If the current meter for one of the unit’s KT120’s has moved to
the left of the parallel lines on the meter face, using an
appropriately bladed screwdriver, adjust the potentiometer
directly in front of that tube’s location by turning it clockwise
until the needle has returned to between the meter’s parallel
lines. If the meter needle has moved to the right of the parallel
lines on the meter face, turn the potentiometer control
counter-clockwise to correct.
As with all tube equipment, changing tubes from one
manufacturer’s to another’s may alter the sonic characteristics
of the equipment.
All consequences of changing or attempting to change tubes are
borne by the user unless by express agreement between the
owner and Allnic Audio USA. Allnic Audio and Allnic Audio USA
are not liable in any way whatsoever for any injury or loss
incurred by the user or for damage to the A-2000, any of its
parts, or tubes or replacement tubes resulting from the user
changing or attempting to change tubes.
SPECIFICATIONS FOR THE ALLNIC AUDIO A-2000 KT120
STEREO POWER AMPLIFIER
Output Power: 70w x 2 (8Ω load, at 1KHz)
Distortion: 0.2% at 1KHz at 10w
Frequency Response: 20Hz - 20KHz Flat

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S/N Ratio: -80dB (CCIR, 1KHz)
Damping Factor: 8 at 8Ω load at 1KHz
Voltage gain: +24dB
Input Impedance: 100KΩ (single-ended, unbalanced)
Input Sensitivity: 1.4V for rated power
Tubes: KT120 X 4 (power triode)
E282F X 4 (second stage drivers)
6AK6 X 2 (first stage driver)
Fuses: AC Mains - 3A / 250V (110W) (two
supplied – one is a spare). Tubes -
0.5A, 250V, 20mm glass type
Dimensions: (W x D x H) 430mm (16.93 inches)
X 430mm (16.93 inches) X
240mm (9.45 inches)
Weight: 40Kg (88.2 lbs) net.
55Kg (121 lbs) shipping weight.
WARRANTY
All Allnic Audio amplifier products are warranted against materials and manufacturing defects for parts, excluding tubes, and
labour for two (2 years from date of purchase. Tubes are warranted against materials and manufacturing defects for one (1 year
from date of purchase. The warranty is transferable for the balance of the original purchaser’s warranty period, provided, as
stated below, no unauthorized repairs or modifications have been performed on the product. Date of purchase is the date
indicated on the invoice for the product issued by Allnic Audio USA.
For the warranty to be valid, a defective product must be returned to Allnic Audio USA for service prior to any unauthorized
attempt to repair. Any repair work on an Allnic Audio product not specifically authorized by Allnic Audio USA will void the
warranty on the product.
Figure 4 – A-2000 Rear Panel View

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Figure 5 – A-2000 Front Panel View
Figure 6 – A-2000 Chassis Top View