Lab.gruppen LAB 4000 User Manual

USER MANUAL HEADLINES

Unpacking 2

Warnings 2

User responsibility 2

1. Speaker damage

2. Speaker output hazard.

3. Radio interference.

Introduction 3

1. Front panel

2. Rear panel

Installation 4

1. Mounting

2. Cooling

3. Operating voltage

4. Grounding

5. Power consumption

6. Denmark: National deviation

7. Switzerland: National deviation

8. Input connections

9. Connecting speakers

10. Impedance matching (MLS-switches)

Operation modes 8

1. Stereo

2. Tandem mono

3. Bridged mono

4. Stereo reverse

Operation 8

1. Operation precautions

2. Powering up -Soft start

3. Input attenuators

4. Gain switch

5. Indicators

LAB 4000

USER MANUAL

Rev. 3

Design features 10

• Cooling

• Light weight

• Regulated power supply

• Safety approvals

• EMC approvals

Specifications

•

EMC-declaration

Appendix A 12

•

Mains voltage selection

Maintenance 12

Troubleshooting 12

Warranty and disclaimers 13

• General

• International

Technical assistance and services 13

• International

• Factory services

Protections 9

1. Clip-limiter

2. Thermal protection

3. VHF protection

4. Short circuit protection

5. Adaptive Fuse Saver (AFS)

6. AC mains voltage protection

7. D.C. protection

Unpacking

Carefully open the shipping carton and check for any noticeable damage. Every LAB.GRUPPEN amplifier is tested and inspected before leaving the factory and should arrive in perfect condition. If found to be damaged, notify the shipping company immediately. Only the consignee may institute a claim with the carrier, for damage incurred during shipping. Be sure to save the carton and packing materials for the carrier's inspection. It is also advisable, to save the carton and packing material, even if the amplifier is undamaged. Should you ever need to ship the amplifier, use the original packing.

Warnings

Read this before you are operating your amplifier:

• Do not use this amplifier if the power cord is

broken or frayed.

• Always operate the unit with the chassis

ground wire connected to the electrical safety earth.

• Do not parallel or series connect an amplifier

output, with any other amplifier output. Do not connect the amplifier output to any other voltage source, such as battery, mains source, or power supply, regardless of whether the amplifier is turned on or off.

• Do not run the output of any amplifier back

into another channel's input.

• Do not block the air intake or exhaust ports.

Do not operate the amplifier near heat producing devices such as radiators, stoves etc.

• Do not spill water or other liquids into or on

the unit. Do not operate the amplifier if suspected or standing in liquid.

• Do not remove top or bottom covers. Removal

of the cover will expose hazardous voltages. There is no serviceable parts inside and removal may void warranty.

• Keep this manual for future reference.

User responsibility

1. Speaker damage Your amplifier is very powerful and can be

potentially dangerous to both loudspeakers and humans alike. Many loudspeakers can be easily damaged or destroyed by overpowering, especially with the high power available from a bridged amplifier. Always check the speakers continuous and peak power capabilities. Even if the gain is reduced by using the amplifier's front panel attenuator, it is still possible to reach full output power, if the input signal level is high enough.

2. Speaker output hazard Power amplifiers are capable of producing hazardous output voltages. To avoid electrical shock, do not touch any exposed speaker wiring, while the amplifier is operating. See page 6 about outputs for proper connection of speakers.

3. Radio interference

This product has been tested, and complies with the limits for the European Electro Magnetic Compatibility (EMC) directive. These limits are designed to provide reasonable protection against harmful interference between electrical equipment. This product uses radio frequency energy, and if not used or installed in accordance with the operating instructions, it may cause interference to other equipment, such as radio receivers. However, there is no guarantee for no interference even if the amplifier is EMC approved. If the amplifier cause interference, which can be easily determined by turning the amplifier on and off, the user can correct the interference by one or more of the following steps:

1. Increase the proximity between the equipment.

2. Connect the AC cord to an outlet on a different

circuit from that to which the affected unit is connected.

3. If a radio receiver is interfered (normally

amplitude modulation); reorient the antenna.

4. Check if the affected unit complies with the

EMC limits for immunity, (CE-labelled).

If not, address the problem with the manufacturer or supplier. All electrical products sold in the EC must be approved for immunity against electromagnetic fields, high voltage flashes, and radio interference.

Introduction

Thank you for purchasing a LAB.GRUPPEN power amplifier. The amplifier you have chosen is the culmination of many years of Research and Development. This amplifier makes amplification more controllable instead of the traditional "Boring black box" you have become accustomed to. Please take some time and read this manual to familiarize yourself with the advanced features of this amplifier.

The front panel

634 56 8 9

CH. A

-10

-12

-16

-20

-40

-80 dB

Figure 1. Front panel

1. Carry/protection han dle Both handles can be used to carry the amplifier, they

als o act as protect ion for the front panel. If so desired they can be remove d (by removing the screws behind the front panel) for fixed installations, or racks where the front covers are to shal low.

2. Input level attenuators These controls are used to alter the signal level

entering the amplifier. They are calibrated in dB to help set up active loudspeaker systems or cut down unwanted noise from the input signal. (See page 9).

3. Over temp erature protect indicator This indicator is lit if the amplifier tries to operate

above its maximum operating temperature(90oC). The indicator first comes on as a warning to either turn down the input level or check the cooling arrangements after which point the amplifier will mute the input signal. When the cooling fans have returned the output heat sinks to the normal operating temperature the input signal is unmuted.

4. VHF protect indicator

This indicator lights when constant signals, above 12 kHz at full power, are present at t he output terminal s. When this happens the input signal is muted and the process cycles until the VHF signal is no longer present. (See page 9).

VHF

TEMP

CLIP

-5

-10

-15

-20

CH. B

-25

-10

-7

-5

-3

-1

-12

-7

-16

-5

-20

-3

-40

-1

-80

4000 CONVERTIBLE POWER AMPLIFIER

5. Clip/limit indicator

This indicator tells when the amplifier output is clipping or limiting. The two different states can be told apart:

• When the clip limiter is engaged it flickers

briefly. (See page 10).

• When the clip limiter is not engaged it lights for

a longer period.

6. Fan grill filter. A foam filter is located behind the front panel to

prevent dust entering the amplifier.

7. Power actuator

This is used to start th e amplifier. (See page 5 and 8)

8. AC ind icator

Indicate if AC voltage is present .

9. AFS indicator

Indicate if the adaptive fuse saver is activated.

AFS

722

The rear panel

OUTPUT CH.B

MLS

Switch

-2

1+ CH.B+

1- CH.B-

-4

-5

Clip LimiterClip Limiter

Off

Made in Sweden

4 5 6 8 5

CH. B

XLR

1/4“

Pin 1 Gnd Sleeve 2 Pos Tip

3 Neg Ring

INPUT

Rever se Pol. B

Norm al Pol. B

Mono Bridge

230V AC 40-440Hz

Power consumption: 2300 wattsMust be grounded

Link A+B

Gain 29 dB

Gain 41 dB

Stereo

4 1

CH. A

On Off

Clip Limiter

4000

Patent pend

Clip Limiter

Ser. N:o Removed!

OUTPUT CH.A

MLS

Switch

-2

-4

1+ CH.A+

-5

1- CH.A-

3 9 3 2

Figure 2. Rear panel

1. Speaker connector This type of speaker connector may be unfamiliar to

some users. A full description is found in the operation section. (See page 7).

2. MLS™ switches These switches are used to select the maximum

output power . (See page 7).

3. Clip limiter switch. Turns the clip limiter on and off. (See page 9).

4. Input jack Altern a tive to using input XLR or for linking inputs

with other amplifiers. (See page 6).

Installation

1. Mounting

The amplifier is two rack units high (2U) and will mount in a standard EIA 19 inch rack. Amplifiers may be stacked directly on top of each other. There is no need for spacing between units. If it is the intention to fill a rack with amplifiers, we recommend racking is started from the bottom of the rack. It is also recommended that rear supports are used for amplifiers mounted in the middle of the rack, especially if used as part of a portable system.

2. Cooling

Your amplifier uses forced air cooling system to maintain a low and even operating temperature. All LAB.GRUPPEN amplifier, which are fan ventilated, have front to rear cooling. There are several reasons for this, one is that there's usually cooler air outside the rack than inside and therefore the amplifiers can run at higher continuos power levels without thermal problems. Never try to reverse the air flow, as the Intercooler® need a

pressure chamber between the fans and heat sink, and this only works in one direction of the air flow (see Design features on page 8).

5. Input signal XLR (See page 6).

6. Phase reverse swi tch for chan nel B

For reversing the input signal phase of channel B to

allow bridged operation. (See page 8).

7. Link switch

Allows a single input to drive both channels

simultaneously. (See page 8).

8. Gain select switch

Allows amplifier gain to be switched between 29dB

and its normal gain at 0.775mV input sensitivity. (See page 9).

9. AC line cord (See page 5)

Should a heat sink get too hot, its sensing circuit will mute the hot channel. If the power supply overheats, another sensing circuit will mute all output channels, until it cools down to a safe operating temperature. Make sure that there is an adequate air supply in front of the amplifier and that the rear of the amplifier has sufficient space to allows the exhaust to escape. If the amplifier is rack mounted, do not use covers or doors on the front or rear of the rack. For fixed installations with a central cooling system, usually found in fixed installations with a dedicated rack room, it may be necessary to calculate the maximum heat emission. Refer to Power consumption on page 5.

3. Operating voltage

A label just below the mains cable on the rear of the amplifier indicates the AC mains voltage, for which the amplifier is wired. Connect the power cable only to the AC source referred to on the label. The warranty will not cover damage caused by connecting to the wrong type of AC mains. For converting a 230 volt amplifier to 115 volt or vice-versa, see Appendix A.

+ 9 hidden pages

Lab.gruppen LAB 4000 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual