Lab.gruppen LAB 1200C, LAB 1300C, LAB 1600, LAB 300, LAB 4000 User Manual
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fi 300
Power specifications: stereo 8 ohms 4 ohms 2 ohms
EIA at 1 kHz and 1% THD 100 W 150 W 160 W
◆ Cooling; Conventional (no fan)
◆ Protection; Short circuit, DC, high temperature, turn on, VHF and clip limiters
◆ Dimensions in mm (inch); 483 (19")W 244 (1.75")H 2280 (11")D
◆ Weight; 7.5 kg (17 lbs)
fi 500
Power specifications: stereo 8 ohms 4 ohms 2 ohms
EIA at 1 kHz and 1% THD 180 W 290 W 320 W
◆ Cooling; One proportional speed fan
◆ Protection; Short circuit, DC, high temperature, VHF and clip limiters
◆ THX version; LAB 500T
◆ Dimensions in mm (inch); 483 (19")W 288 (3.5")H 2265 (10.5")D
◆ Weight; 11 kg (24 lbs)
fi 1000
Power specifications: stereo 8 ohms 4 ohms 2 ohms
EIA at 1 kHz and 1% THD 380 W 600 W 700 W
◆ Cooling; Two proportional speed fans
◆ Protection; Short circuit, DC, high temperature, VHF and clip limiters
◆ THX version; LAB 1000T
◆ Dimensions in mm (inch); 483 (19")W 288 (3.5")H 2355 (14")D
◆ Weight; 18 kg (40 lbs)
fi 1200C
Power specifications: 4 channel MLS 8 ohms 4 ohms
EIA at 1 kHz and 1% THD 8 370 W 650 W*
4 200 W 380 W
◆ Cooling; Two proportional speed fans
◆ Protection; ALS™ short circuit protection, DC, high temperature, turn on,
VHF, over and under voltage and clip limiters
◆ Dimensions in mm (inch); 483 (19")W 288 (3.5")H 2335 (13.2")D
◆ Weight; 8.7 kg (19 lbs)
Efficient cooling system with turbulent air flow.
Lab.Gruppen force cooled amplifiers
have front to rear cooling. The main reason for this is because there is usually
cooler air outside the rack than inside or
behind (usually a closed rack with minimal venting because of cables).
Lab.gruppen
– the company and the products
Lab.gruppen currently produce
eight power amplifier models of which
five utilize switch mode power supplies
(SMPS) and three utilize conventional
power supplies. These models range
from 23150 W to 232400 W.
Whilst many competitors strive to
produce as many models as possible it
should be noted that since 1987 none of
our SMPS products have been “discontinued”. Products are often improved
allowing existing users to upgrade in
many cases.
An area of pride is safety compatibility – all of the products meet the
European safety approval IEC-65, and
the switch mode products meet the
European EMC rules. During the first
quarter of 1995 most products were
CE approved.
For installations in cinemas there are
two variants, which are THX approved.
Cooling system
Lab.Gruppen fan cooled amplifiers
utilize a special copper cooling system
called Intercooler
®
(copper conducts
heat twice as good as aluminium).
Output devices (always bi-polar) are
mounted directly on a compact heatsink that produces turbulent airflow for
maximum heat dissipation. The airflow
in front of the heatsink is maintained by
a pressure chamber and two proportional speed fans. A major advantage of
the Intercooler® is that there are only a
few degrees difference between all the
devices. Compare this to a conventional
cooling tunnel where there can be variances of up to 40 degrees between devices.
With such a difference, matching complementary devices makes no sense!
Current voltage characteristic of different power supply topologies.
1) Conventional power supply show voltage
drop due to internal resistance
2) Regulated power supply used by Lab.gruppen
3) Unregulated switch mode power supply with
current limiting.
the same characteristics
as a conventional supply. We have avoided
the pitfalls of push-pull
converters, by eliminating the need for limiting on the secondary
side of the switch transformer. This is achieved by using sense
windings, injecting a magnetic pulse
from the AC-line during a pulse time
segment, which is separated from the
output charge current pulse.
Protection circuits
Lab.Guppen power amplifiers have many advanced
protection features that
will protect both power
amplifier and speakers
connected to it, should
a fault condition arise.
Under normal
use these
features are
inaudible and
all protection
circuits are
independent.
◆ DC protection
There are two types of DC protection;
Fuses on the supply branches of each
channel (this is an IEC 65 requirement),
and a Crowbar protection that shorts
the output.
◆ Thermal protection
Protects the amplifier from overheating and causing damage to the
output stages. Indicators come on
before the signal is muted.
◆ Short circuit protection
Protects the amplifier by limiting the
power being driven into the short circuit.
Some amplifiers are equipped with
Lab.Gruppen ’s Adaptive Limiting system
(ALS™), which holds the output devices
in their safe operating areas yet permits
high peak currents.
◆ Clip limit protection
All amplifiers are equipped with clip
limiters, which can be enabled via the
amplifiers’ rear panels. They are not
simple DC detectors, but actually maintain a maximum distortion of 1%
reaching the loudspeakers. As a by-product, when the amplifier comes out of a
protect condition, the output level has a
slow rise time. The effect is like turning
the gain up slowly.
◆ VHF protection
Protects the loudspeaker against nonmusical signals, outside the audible area.
This protection is not a simple R.F. filter,
as found in other designs.
LAB.GRUPPEN POWER AMPLIFIERS
Lab.Gruppen was founded in 1979, and have since then been
designing and manufacturing power amplifiers and active cross-
overs/ speaker processors, utilizing ground breaking technologies.
Apart from high reliability and excellent sound quality, the power
amplifiers are characterized by good power to weight ratio and
size. The crossovers and speaker processors are noted for good
value for money as well as total flexibility.
It is however, the switch mode power amplifiers that have made
Lab.Gruppen world leaders in this field since 1987.
Lab.Gruppen products are currently exported to more than
twenty countries including the Americas, Africa and Asia.
Transformer core made of ferrite, used in the
Lab.gruppen switch mode amplifiers, compared with
conventional transformer made with iron core.
Switch mode power supply (SMPS)
Switch mode power supplies are the
modern solution to the problems of size
and weight. However, early examples of
SMPS used in power amplification were
not ground breaking, and literally
adopted the type of supply found in
many computers today.
The Lab.Gruppen SMPS is different
in that it is regulated. How is this
achieved? In contrast to other designs,
that use push pull converters, we have
managed to produce a SMPS that has
Upper curve shows the LAB 2002 power bandwidth in
4 ohms. US made conventional unit below.
Switch mode amplifiers
Apart from exellent sound quality, the
switch mode amplifiers possess high
power to weight ratio (480 W/kg in the
case of the LAB 4000 – the best in any
class), and a regulated power supply.
This product line consists of the
LAB 4000, LAB 2002, LAB 1600, LAB
1300C and the LAB 1200C.
The LAB 1200C is a four channel amplifier, which can be co nfigured in a variety
of ways, anything from 42350 W to
22600 W, at eight ohms!
The LAB 2002 and the LAB 4000
utilizes a switch mode output stage, which
makes it three times more efficient than
a conventional class AB amplifier.
Whilst the SMPS may sound complex
it is actually very straight forward with
high reliability. The net result is good
bass and fast response.
Because the supply is regulated, the
power amplifier will produce the same
power output even if the AC line falls by
more than 20% !
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