Lab.gruppen LAB 4000 User Manual

USER MANUAL HEADLINES

		LAB 4000
		USER MANUAL
Unpacking	2	Rev. 3
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)

Design features

10

•Cooling

•Light weight

•Regulated power supply

•Safety approvals

•EMC approvals

Specifications

11

•EMC-declaration

Appendix A

12

•Mains voltage selection

Operation modes		8	Maintenance		12
1.	Stereo		Troubleshooting		12
2.	Tandem mono
3.	Bridged mono
4.	Stereo reverse		Warranty and disclaimers		13
Operation		8	•	General
			•	International
1.	Operation precautions
2.	Powering up -Soft start		Technical assistance and services		13
3.	Input attenuators
4.	Gain switch		•	International
5.	Indicators		•	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

1

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.

2

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
6			3	4		5		6	8	9
					VHF
					TEMP					AFS
					CLIP					AC
					-5
					-10
					-15
		CH. A			-20		CH. B
					-25
	-12	-10	-7		ON	-12	-10	-7
	-16			-5		-16		-5
	-20			-3		-20		-3
	-40			-1		-40		-1
	-80	dB	0			-80	dB	0
					4000			CONVERTIBLE POWER AMPLIFIER
1		2					2			7

Figure 1. Front panel

1.Carry/protection handle

Both handles can be used to carry the amplifier, they also act as protection for the front panel. If so desired they can be removed (by removing the screws behind the front panel) for fixed installations, or racks where the front covers are to shallow.

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 temperature 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 the output terminals. When this happens the input signal is muted and the process cycles until the VHF signal is no longer present. (See page 9).

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 the amplifier. (See page 5 and 8)

8.AC indicator

Indicate if AC voltage is present .

9.AFS indicator

Indicate if the adaptive fuse saver is activated.

3

The rear panel

1

4

5

6

7

8

5

4

1

INPUT

CH. A

OUTPUT

.B

CH. B

B

.l B

OUTPUT CH.A

M LS

S w itc h

N o rm al P o .l

R ev er se P o

S t e re o L ni k A + B

Ga ni 4 1 dB

Ga ni 2 9 dB

M LS

S w itc h

d B

d B

0

Mono Bridge

0

-2

- 2

1+ CH.B+

-4

XLR

1 / 4 “

- 4

1+ CH.A+

-5

On

Off

On

Off

- 5

1- CH.B-

Pin 1

Gnd

Sleeve

1-

CH.A-

Clip Limiter

Clip Limiter

2

Pos

Tip

Made in Sweden

3

Neg

Ring

230V AC

40-440Hz

4000

Patent pend

Ser. N:o

Removed!

Must be grounded

Power consumption: 2300 watts

2

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

Alternative to using input XLR or for linking inputs with other amplifiers. (See page 6).

5.Input signal XLR (See page 6).

6.Phase reverse switch for channel 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)

Installation

Should a heat sink get too hot, its

sensing

circuit

1.

Mounting

will

mute

the hot channel. If the power

supply

overheats, another sensing circuit will mute all

The amplifier is two rack units high (2U) and will

output channels, until it cools down to a safe

mount in a standard EIA 19 inch rack. Amplifiers

operating temperature.

may be stacked directly on top of each other. There

Make sure that there is an adequate air supply

in

is no need for spacing between units. If it

is

the

front of the amplifier and that the rear of the

intention

to

fill

a

rack

with

amplifiers,

we

amplifier has sufficient space to allows the exhaust

recommend racking is

started from the bottom of

to escape. If the amplifier is rack mounted, do not

the rack. It is also recommended that rear supports

use covers or doors on the front or rear of the rack.

are used for amplifiers mounted in

the middle of

For

fixed

installations

with

a

central

cooling

the

rack, especially

if

used

as

part of

a portable

system, usually found in fixed installations with a

system.

dedicated rack room, it may be necessary

to

2.

Cooling

calculate the maximum

heat

emission.

Refer

to

Power consumption on page 5.

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

3.

Operating voltage

several reasons for this, one is

that

there's

usually

A label just below the mains cable on the rear of

cooler air outside the rack than inside and therefore

the amplifier indicates the AC mains voltage, for

the

amplifiers can run at

higher continuos

power

which the amplifier is wired. Connect the power

levels without

thermal

problems.

Never

try

to

cable only to the AC source referred to on the label.

	reverse the air flow, as the Intercooler® need a	The warranty will not cover damage caused by
		connecting to the wrong type of AC mains.
	pressure chamber between the fans and heat sink,	For converting a 230 volt amplifier to 115 volt or
		vice-versa, see Appendix A.
	and this only works in one direction of the air flow
	(see Design features on page 8).

4