Lab12 MK2 Voice Toroid Version Owner’s Manual
- September 27, 2024
- LAB12
Table of Contents
MK2 Voice Toroid Version
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Specifications
- Brand: Lab12
- Model: suara
- Power Output: 2 x 50W Class A
- Amplifier Type: Power Amplifier
- Country of Origin: Greece
- Website: www.lab12.gr
Product Usage Instructions
Unpacking
Suara should be removed from its box with care. Remove all the
foam protective pieces of the box before you unpack suara. Unpack
suara with your hands on both sides of the device.
Warnings
No user serviceable parts are included inside. Do not unscrew
the cover; high voltages remain after disconnecting from mains. In
case your device requires any kind of service or upgrade, please
ship or take your equipment directly to Lab12 or to one of our
authorized dealers or other qualified personnel. Always use same
type of fuse for replacement.
Installation & Placement
Suara Tubes Positions:
Insert the tubes carefully in each position. All tubes are marked
with a position number and perfectly matched during calibration for
balanced operation.
Suara Front panel:
The front panel features three indication LEDs and two VU meters
for monitoring output levels accurately.
Rear Panel
Connection Inputs and Outputs:
The rear panel includes IEC AC input with a main fuse holder, RCA
and XLR connectors for signal inputs, speaker outputs for 4 or 8
ohm impedance matching, and bias setting for easy adjustment.
FAQ
Q: How long does the suara need to reach optimal
performance?
A: The suara needs at least 200 hours of listening to reach
optimal performance as all components go through a burn-in
period.
Q: What should I do if my device requires service or
upgrade?
A: If your device needs service or an upgrade, ship it directly
to Lab12 or one of their authorized dealers or qualified
personnel.
Q: How do I set the bias on the suara amplifier?
A: The bias setting and check can easily be achieved from the
back panel. Refer to page 9 of the manual for the bias
procedure.
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Owner’s Manual
suara
Parallel tubes 2 x 50W Class A Power Amplifier
www.lab12.gr
v1.6
Lab12 suara 2 x 50W Class A Power Amplifier
K. Varnali 57A, Metamorfosi, 14452, Athens, Greece Tel: +30 210 2845173 Email:
contact@lab12.gr Web: www.lab12.gr
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Lab12 suara 2 x 50W Class A Power Amplifier
Table of Contents
It is yours………………………………………………………………….. 4 Unpacking and
warnings………………………………………….. 4 Features…………………………………………………………………….. 5
Installation & Placement………………………………………….. 5 Suono Tubes
Position……………………………………………….. 6 Front Panel………………………………………………………………… 7 Rear
Panel…………………………………………………………………. 8 Main connections………………………………………………………. 9
Bias Setting……………………………………………………………….. 10 For the safety of your
equipment……………………………… 10 Specifications……………………………………………………………. 11
Page 3 of 12
IT IS YOURS!
Thank you for selecting Lab12 suara, an audiophile Parallel tube Class A power
amplifier. Every component on it is designed to provide smooth and untreated
sound. It is a full tube amplifier with 4x NOS Russian driver tubes and
4xKT150 or 4xKT120 on power stage. Suara can cooperate gratefully with any
preamplifier on the market and it is the perfect match for Lab12 pre1. Suara
has the ability to nail you down on your couch and make you listen all your
music collection again. 50 Watt of power for any pair of speakers is available
but the most remarkable point is that you will receive a fluid, wide and
addictive consonant sound with any choice of music style. All components are
carefully chosen after hours of listening and testing, while paying great
attention to every detail affecting the outcome. As every Lab12 device, suara
has an ultra-solid construction with glass blasting anodized finishing and
retro analogue V/U meters.
Do not forget that your suara is totally handcrafted with perfectly matched
parts of the finest selections. In order to reach the optimal performance,
your suara needs at least 200 hours of listening. In this time all components
go from “burn in” period to stable. Before setting up your new suara, we
encourage you to thoroughly read this manual to properly acquaint yourself
with its features. We love music and audio devices and we have built your new
device with emotion and personal treatment.
The information contained in this manual is subject to change without notice.
The most current version of this manual is available on our official website
at http://www.lab12.gr
Unpacking
Suara should be removed from its box with care. Remove all the foam protective
pieces of the box before you unpack suara. Unpack suara with your hands on
both sides of the device.
Warnings
No user serviceable parts are included inside. Do not unscrew the cover; high
voltages remain after disconnecting from mains. In case your device requires
any kind of service or upgrade, please ship or take your equipment directly to
Lab12 or to one of our authorized dealers or other qualified personnel. Always
use same type of fuse for replacement.
Lab12 suara 2 x 50W Class A Power Amplifier
Features
· 6550, KT88, KT120, KT150 compatible · Easy Manual Bias Adjustment on the
back plate · Triode / Ultra Linear selector switch · Handcrafted custom audio
grade transformers. · No feedback design · Special audio grade matched parts
in every stage · SRSG® implementation · Fine symmetry® implementation · Analog
retro Nissei VU meters · 5mm Aluminum face panel · Five Years Guarantee
Installation & Placement
Lab12 suara should be placed on a solid, flat surface. You should avoid
placing it near a heat source as this could compromise suara’s performance and
reliability. Carefully put the tubes in dedicated sockets. Make sure that
tubes are perfectly snapped into sockets. See bellow page. Due to high power
tubes design, suara’s chassis could be hot so you should never place another
hot component directly near this device. Make sure that the device has enough
space to ventilate. Tubes will be hot, this is normal. Be careful not to touch
the tubes during the operation to avoid any injuries. Take care of the glass
blasting anodized finish of front panel with a soft cloth. No need to use any
sprays or polishes. Never use cleaners containing abrasives, as this will
damage the surface.
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Lab12 suara 2 x 50W Class A Power Amplifier
Suara Tubes Positions
Insert the tubes carefully in each position. All of the tubes are marked with
the position number was placed during calibration and factory burn in of
suara. All in box tubes are perfectly matched during calibration to achieve a
perfect balanced operation.
V1 : KT150 / KT120 V2 : KT150 / KT120 V3 : KT150 / KT120 V4 : KT150 / KT120
Suara Top
V5 : 6n2p V6 : 6n1p V7 : 6n1p V8 : 6n2p
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Front Panel
Lab12 suara 2 x 50W Class A Power Amplifier
Suara Front panel
In the front panel you will see three indication LEDs and two VU meters. The
three LEDs (C) indicate that the device is powered on. To the left of the 3
LEDs you will see a retro analog VU meter (A). You can accurately monitor the
output level of left channel on dB scale. To the right of the 3 LEDs you will
see a retro analog VU meter (B). You can accurately monitor the output level
of right channel on dB scale.
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Rear Panel
Lab12 suara 2 x 50W Class A Power Amplifier
SUARA Rear panel
In rear panel you will find the connection inputs and outputs. To the right
side you will find an IEC AC input including a main fuse holder (E). A pair of
RCA and XLR connectors for each channel (C) are the inputs of signal from your
preamplifier. Speaker outputs for each channel (A & D) giving you the choice
of 4 or 8 ohm output for perfect matching with your speaker impedance. Bias
setting and check can easily be achieved from the back panel (B). Please find
the bias procedure on page 9.
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Lab12 suara 2 x 50W Class A Power Amplifier
Main connections
Connect a High-Grade Power cable to the IEC input and to your wall socket.
Make sure that your wall socket provides a good ground before connecting the
power cable. (Every suara is tuned and calibrated using the Lab12 Knack mk2
Power Cable. We strongly suggest using this cable).
Connect to your Preamplifier
Connect the preamplifier analog output to the analog line level input (RCA or
XLR cables) of your suara Power Amplifier. Make sure about the correct channel
connections. We suggest you use a good quality interconnect cable pair.
Connect your Speakers
Connect your speakers to the additional output of suara (connect speakers from
2 to 4 ohm at 4ohm positive bind, speakers from 6 to 16 ohm at 8ohm bind).
Make sure about the phase and polarity of speakers, always connect ’plus” (red) bind of suara to’plus” (red) bind of speaker and same with black.
Triode / Ultra Linear
You can choose the operation of suara between Triode or Ultra Linear pentode
mode, to tune the sound closest to your taste. This can be done with two
toggle switches on the top cover. Position both switches towards to
transformers for Triode mode or towards to tubes for Ultra Linear pentode
mode. Always do this selection with your amplifier turned off.
Notes:
Suara is fully compatible with the best octal tubes (6550, KT88, KT120,
KT150). You can use any of these four types of tubes with no problem. Please
always set correct bias immediately after any tube change, always use matched
pairs of tubes (contact lab12).
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Lab12 suara 2 x 50W Class A Power Amplifier
Bias Setting
Please contact a qualified person or your local dealer if you are not sure
about this procedure. You can easily set the bias of each tube from the back
panel of the amplifier. You must use a DC multimeter. Please set multimeter in
5VDC range. Turn on the amplifier (with connected speakers at outputs and
connected inputs without signal). Connect minus (black) terminal of multimeter
at any minus (black) speaker bind. Connect plus (red) terminal of multimeter
at test point of tube you need to bias. Use trimming screwdriver to set the
voltage at 950mVDC(KT150 setting) or 850mVDC(KT120 setting) from corresponding
trimmer. Follow the same procedure for each tube. Wrong bias will destroy your
tubes and possibly your amplifier. Always adjust new tubes bias current
immediately after turning on. Repeat bias procedure at least 3 times the first
5 hours of using.
For the safety of your equipment ! Make sure that all your equipment is turned
off before any connection. ! To avoid damaging your speakers you have to turn
on suara some seconds after turning on your preamplifier and turn it off some
seconds before turning off your preamplifier. ! Never turn on suara without
connected speakers or preamplifier on it. It is possible to damage tubes or
even output transformers.
Page 10 of 12
Lab12 suara 2 x 50W Class A Power Amplifier
Specifications
· Power: 230VAC 50Hz (115VAC 60Hz) · Power consumption: 350 VA max · Output
power: 50 Watt per channel (KT 150) · Frequency response: 20 Hz-25 KHz
(-0.9dB) · Input impedance: 100 Kohm · Recommended speakers: 4-8 ohm · Tube
complement: 4x dual triodes, 4x KT-150 Power Pentodes · Input sensitivity:
1.8V triode mode / 1.5V Ultra Linear mode · Inputs: 1x line unbalanced stereo
(RCA and XLR connectors) · Available Colors: Matt Black, Frozen Silver ·
Dimensions (WxHxD): 43x19x29 cm · Weight: 20.5Kg
Warranty
This device has 5 years warranty for all parts (or 90-Day Limited Warranty for
vacuum tubes) from the day of purchase.
We wish you to enjoy your new device exactly as we enjoyed it when we built it
for you!
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Lab12 suara 2 x 50W Class A Power Amplifier
K. Varnali 57A, Metamorfosi, 14452, Athens, Greece Tel: +30 210 2845173 Email:
contact@lab12.gr Web: www.lab12.gr
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