Allnic T1500 User guide

ALLNIC AUDIO

- T-1500 -

300B SET STEREO INTEGRATED AMPLIFIER

OWNER’S MANUAL

ALLNIC AUDIO
T-1500 300B SET STEREO INTEGRATED AMPLIFIER

Thank you for purchasing the Allnic Audio T-1500 300B SET Stereo
Integrated Amplifier. We are certain your trust in Allnic Audio and
Hammertone Audio, as well as your appreciation for the sound of this high­quality device, will be rewarded by its excellent operation for years to
come.

Please read this entire manual before you connect the T-1500 300B SET
Stereo Integrated Amplifier to the other components of your system and
the wall outlet.

252 Magic Drive, Kelowna, British Columbia, Canada V1V 1N2
Direct Telephone: [phone]; Fax: [phone];
Cell: [phone]
email: [email protected]
Website: www.hammertoneaudio.com

** Information and specifications for the Allnic Audio product described

in this manual are subject to change without notice.

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TABLE OF CONTENTS:

___________________________________________________________________

INTRODUCING THE
___________________________________________________________________

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
___________________________________________________________________

T-1500 300B SET STEREO INTEGRATED AMPLIFIER 4

OPERATION – CHASSIS AND REMOTE CONTROLS 7
The Current Meters
___________________________________________________________________

TUBES AND TUBE BIAS 7
___________________________________________________________________

SPECIFICATIONS 7
___________________________________________________________________

WARRANTY 8
___________________________________________________________________

FIGURES 8

Please read about SAFETY before you attempt to use the T-1500 - we care
about our customers and the equipment, and we want you to enjoy this
product for a long time!

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INTR

ODUCING THE

T-1500

300B SET

STEREO

INTEGRATED AMPLIFIER

amplifiers.

The T-1500 stereo amplifier is Allnic Audio’s top of the
line 300B SET stereo integrated amplifier model. Like all
Allnic Audio products, the T-1500 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 T-1500 has the following features:

 12.5 watts per channel of pure class A high power output.

The T-1500 is a single ended power amplifier. Almost all
other 300B amplifiers are under, and distortion, driven.
This is a result of the use of conventional "Resister­Capacitor" circuits, which give only up to around a 70V
swing voltage, with high distortion. This means that an
already distorted signal of a lower than optimum swing
voltage is directed to the deep biased 300B grid. Allnic’s
powerful "Inductor Drive" circuit gives up to a 150V swing
voltage, with very low distortion (about 0.3%). It is this
drive delivered to the T-1500 that allows for a higher
output (12.5w) than the approximately 8 - 10w output that
could be expected from standard 300B circuits.

 Allnic also uses a very big nickel core, so as not to be

magnetically saturated at a high current of level of 100mA.

 Long life and trouble-free operation. Allnic employs a “soft

start circuit” to protect the tubes and other parts. It applies
the high B+ voltage only after tubes are fully warmed-up.

 Fixed bias control grid. Allnic prefers to use low distortion and

high output “fixed bias” rather than the relatively higher
distortion and lower output “self-bias” method. That way, it is
possible to eliminate the use of cathode resisters and their
associated heat production.

 Natural negative feedback. The T-1500 applies about -6dB of

negative feedback. This is a very complimentary amount of
negative feedback that differentiates the Allnic 300B single
ended amplifier from the standard, which has a very coloured
and weak speaker driving force. With this natural feedback,
the T-1500 has a relatively high “damping factor', very low
distortion, and a higher S/N ratio, without losing the signature
single ended natural sound quality.

 We use a high quality 41 step silver contact attenuator (all

resistors non-inductive) instead of a carbon filmed slide
potentiometer.

 Real power drive. The driver tube, a PCL86, is a very strong

power pentode/triode. We use this power pentode to
drive the 300B’s via a choke plate inductor. Our choke
inductor (100% nickel permalloy PC core) has very low
power loss and infinitely high load impedance. This
configuration is an ideal drive stage for 300B SET.

 No separate preamplifier section. The T-1500 has only two

gain stages, with a total gain of +35dB. The PCL86 driver
tube gain stage receives the signal directly from the line
inputs. The reduced number of gain stages means less
distortion.

Nickel alloy output transformer. Allnic uses sophisticated
ratio mixed nickel permalloy PB cored output
transformers. Because of their extremely high initial
permeability, it is possible to use lower turns on the
primary winding while retaining very high 'open circuit
inductance”. That means a resulting very wide frequency
range and low distortion bass response. This is another
reason why the T-1500 excels over other 300B integrated

 Beautiful 20KHz square wave response. See Figures 1-3.

Fig.1 Square Wave 50Hz Fig.2 Square Wave 1KHz

Fig.3 Square Wave 20KHz

Measured by LEADER LAG-126 Audio Signal Generator
and KENWOOD CS-4125 Oscilloscope

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

As are all Allnic Audio products, the T-1500 is fully RoHS

CLEANING

(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 T-1500 300B SET stereo

integrated amplifier

 One (1) IEC type power cord
 One (1) Owner’s Manual

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 T-1500.

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

Note:

1) The T-1500 ships with the tubes installed.

2) The T-1500 will work with most IEC type
aftermarket power cords. Of course, only you
can determine the power cord that works most
synergistically with the T-1500 in your system.

3) Be sure the T-1500 is labeled for the AC voltage
of your location. If it is not, please contact
Hammertone Audio.

We advise that you keep the boxes and other packing
materials that your T-1500 came in. It will be useful if
you sell your T-1500 or in the unlikely event you need
to ship it for service.

SAFETY

 Remove ALL protective cushioning material

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 Hammertone Audio.

 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 T­1500 into an AC connection.

 Do not attempt any repairs.
 See the notes on “Location, Location, Location”.

A. LOCATION, LOCATION, LOCATION

Like all audio products using tubes, the Allnic Audio T-1500
needs to be placed on a solid stand in a location that provides
good air circulation around, above and below the stereo
amplifier.

 DO NOT cover the top of the T-1500.
 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 T-1500 on some kind
of after-market isolation feet or similar devices.
Dropping one side of the T-1500, 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 T-1500 is a highly
sensitive piece of electronic designed for neutrality and
will output what you put into it.

 DO try to place T-1500 away from major sources

and potential receivers of RFI and EMI. Though
well shielded, the T-1500 will function best away
from large power transformers and other sources
of such interference and from other equipment
that could be susceptible to such forms of
interference.

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B.

INPUTS

There are four (4) RCA type female inputs. Your interconnects
will require male RCA terminations. Facing the rear of the
chassis, the input connections are to the right of the IEC
power input and the Pre Out terminal pair. The left channel
connector is the top one in each line input pair. Please refer
to Figure 5.

C. PRE OUT CONNECTIONS

The T-1500 has a pair of RCA type female Pre Out
(Preamplifier outputs – refer to Figure 5) connections on the
rear of the chassis, between the IEC connection and the Line
Inputs. The Pre Outs are connected passively; therefore,
when they are in use, the PCL86 and 300B’s continue to draw
power and operate. These connections are for use to connect
to one or a pair of powered subwoofers or, for bi-amping, to
an external stereo power amplifier or pair of monoblock
amplifiers (preferably with the same gain as the T-1500).

C. SPEAKER TERMINALS

The T-1500 is equipped with two pairs of high-quality speaker
terminals. These terminals are located at the left of the back
of the chassis (the right, facing the front of the chassis). The
positive terminal for each pair is on top, the negative below.
Between the pairs of terminals is a vertically oriented toggle
switch to select between either 4 or 8 ohm speaker
impedance or 8 and 16 ohm impedance, as pre-specified by
the owner. The T-1500 utilizes a circuit design that provides
for full power from the output transformer regardless of the
impedance selected with the toggle switch. Set the toggle
switches to your preferred speaker impedance. Facing the
rear of the chassis, the right pair are on the left outside left
and the left channel pair are on the inside right. Facing the
front of the chassis, the right channel pair is on the outside
right and the left channel pair is to their left, on the other
side of the impedance toggle. The terminals accept bare wire
(not recommended) and spade and banana type connectors.
Please refer to Figure 5.

D. POWER CONNECTION

Connect the input interconnects and/or the speaker
cables or the Pre Out connections before you insert the
power cable into the receptacle at the centre of the
chassis rear. The T-1500 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 5.

The T-1500 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 T-1500 in place and all connections have
been made to your turntable and preamplifier, you are ready to
turn on the power for your T-1500; before you power it up,
though, be sure you have:

 removed ALL the cushion materials from inside the tube

chimneys

 checked that all tubes are snug in their sockets and that the

pin alignments for the 300B’s are correct (wide diameter
pins and narrow diameter pins in the correct holes of the
sockets.
mains for the unit, and they should preserve both the tubes
and the amplifier, in case you have removed and replaced
the 300B’s incorrectly. However, you will have to replace
fuses, and the damage to your self-esteem for getting it
wrong may haunt you forever. Hammertone Audio and Allnic
Audio Labs are not responsible for such an outcome.

 ensured the interconnects are firmly attached
 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

Turn on the T-1500 by pushing the on/off vertically mounted
rocker switch, located at the front of the right side panel (facing
the front of the unit) to the “on” position. The “on” position is
with the vertical line on the switch (the upper portion)
depressed and the part of the switch marked with the “o” (the
lower portion) in the raised position. Of course, the off position
is the reverse. After about a thirty to forty (30 - 40) second delay
(the soft start), the T-1500 will be powered on.

This is essential. The 300B tubes are fused, as is the

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OPERATION

-

CHASSIS AND REMOTE CONTROLS

When the power is on, the current meters on the face of the

adjust the bias back into the area between the two parallel lines

chassis will illuminate. From this point on, the T-1500’s
operation is straight-forward. The face of the chassis has an
input selector control knob and a volume control knob (see
Figure 4. The remote control will also control the input
selections and the volume. It will not control the power to the
T-1500, which must be switched on and off manually, as
described above.

When you are finished listening, turn off your T-1500 stereo
amplifier(s) first; then, turn off your preamplifier and sources.

In the case of any failure, please contact Hammertone Audio
for assistance.

THE CURRENT METERS

The illuminated meters indicate the current supply to each of
the two 300B gain tubes in the T-1500. There is a
potentiometer for each 300B (Refer to Figure 6). When you
turn on the T-1500, the needle of the current meter for each
300B should be between the two parallel lines on the meter
face. Any error of current supply to or failure of a 300B 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 300B
tube. You must turn off the T-1500 and replace both the fuse
(0.5A, 250V, 20mm glass type) for that tube and the 300B. To
replace a fuse, using a screwdriver, simply turn the top of the
fuse cap counter clockwise. It will spring out holding the fuse.
Replace the fuse, push the fuse cap down and turn it
clockwise; it will lock itself. If you have any questions about
doing this, please contact Hammertone Audio for assistance.

TUBES AND TUBE BIAS

of the meter for a tube when it is replaced. Please refer to Figure
6 for tube locations.

If the current meter for one of the unit’s 300B’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 counter­clockwise to correct.

All consequences of changing or attempting to change tubes are
borne by the user unless by express agreement between the
owner and Hammertone Audio. Allnic Audio and Hammertone
Audio are not liable in any way whatsoever for any injury or loss
incurred by the user or for damage to the T-1500, any of its
parts, or tubes or replacement tubes resulting from the user
changing or attempting to change tubes.

SPECIFICATIONS FOR THE ALLNIC AUDIO T-1500 300B SET
STEREO INTEGRATED AMPLIFIER

 Output Power: 12.5w + 12.5w (4, 8 or 16Ω load, at

1KHz)

 Distortion: 0.3% at 1KHz, 2.83V

 Frequency Response: 20Hz - 20KHz Flat

 S/N Ratio: -80dB (CCIR, 1KHz)

 Damping Factor: 10 at 8Ω load at 1KHz

 Voltage gain: +35dB

 Input Impedance: 10KΩ (single-ended, unbalanced)

The T-1500 uses the following tubes:

 Two (2) x 300B
 Two (2) x PCL86

Because of the individual bias for each 300B, it is not
necessary to use a matched pair in the T-1500.

You may use any 300B type tube in the T-1500, including the
newer higher voltage varieties. Of course, you will have to

 Input Sensitivity: 230mV for rated power

 Tubes: 300B X 2 (power triode)

PCL86 X 2 (driver tube - equivalent
to 14GW8)

 Fuses: AC Mains - 3A / 250V (110W) (two

supplied – one is a spare). Tubes -

0.5A, 250V, 20mm glass type

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

Dimensions: (W x D x H) 430mm

(16.93

inches) x
330mm ( inches) X 240mm
(9.45 inches)

 Weight: 20Kg (44 lbs) net.

21.8 Kg (48 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 Hammertone Audio.

For the warranty to be valid, a defective product must be returned to Hammertone Audio for service prior to any unauthorized attempt to
repair. Any repair work on an Allnic Audio product not specifically authorized by Hammertone Audio will void the warranty on the product.

Figure 4 – T-1500 300B SET Stereo Integrated Amplifier Front Panel View

Figure 5 – T-1500 300B SET Stereo Integrated Amplifier Rear Panel View

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Figure 6 – T-1500 300B SET Stereo Integrated Amplifier Chassis Top View

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252 Magic Drive, Kelowna, British Columbia, Canada V1V 1N2
Direct Telephone: [phone]; Fax: [phone];
Cell: [phone]
email: [email protected]
Website: www.hammertoneaudio.com

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