QA400

QA Series Power Amplifiers

172.020UK

Introduction

Professional dual channel power amplifiers delivering high quality, dependable performance at an accessible price. Design of these workhorse amplifiers has been focused upon high power delivery without over-complicated features adding excessive costs. Yet still, these units are furnished with multiple connection possibilities and self protection circuitry to ensure that they will deliver, whatever the application.

Features

19” Rackmount (2U)
High power delivery
Multiple input and output connection types
Balanced and unbalanced inputs
Overheat/overload protection

Front panel:

VENTILATION GRILLE - Do not cover or restrict airflow.
CHANNEL A+B LEVEL - Attenuate output levels.
INDICATOR LEDS - Show signal present, clipping or protect mode.
POWER SWITCH - Switches mains power on/off.

Rear panel:

COOLING FAN - Do not cover or restrict airflow.
IEC MAINS INLET - Check voltage and connect to mains with supplied lead.
MAINS FUSE - to replace fuse, disconnect mains & open with screwdriver.
OUTPUT SECTION – Connect speakers using speaker sockets, jack or binding posts.
INPUT SECTION – Connect mixer or other audio source via combo XLR/jack or RCA L+R.

Connection

Operation

Check mains for correct voltage as indicated near to the IEC mains inlet on the rear panel. Connect to mains supply using the IEC cable provided.
Connect the outputs A+B to speakers via speaker connectors, jack or binding posts, ensuring that the minimum impedance is no lower than 4Ω per channel.
When using 8Ω speakers, connect the speakers in pairs to each other and then connect one of each pair to an amplifier channel output.
Connect the mixer or audio source to either the combo or RCA input sockets.
With channel A+B levels down, switch the power on.
Gradually increase channel levels and check for sound from speakers.
If there is no sound, turn down channel levels, switch off and disconnect mains and check connections – if front panel PROTECT LEDs are lit, refer to qualified service personnel.

Maintenance

No user serviceable parts inside, refer all servicing issues to qualified service personnel.

Clean case with a lint-free dry or slightly damp cloth, keep ventilation grille and fans clear of debris

Troubleshoot

No Output

Check mains power is on and fuse is OK
Check leads and connections
Check PROTECT LEDs are not lit
Check speakers are working on another amplifier

Distrorted Output

Reduce the input signal level. Ensure that the amplifier output level is within the maximum rating of the connected speakers and gradually increase the input signal, ensuring that the signal is clean and free from distortion.

If protect mode is active, refer to qualified service personnel.

Specification

Specification	Value
Weight	6.8kg
Dimensions	88 x 482 x 270mm
Power rms @ 8 Ohms	2 x 70W
Power rms @ 4 Ohms	2 x 100W
Power max. @ 4 Ohms	2 x 200W
Fuse rating	T5A (240V) / T10A (110V)
Power supply	110/240Vac, 50/60Hz (IEC)
THD	0.25%
SNR	90dB
Inputs	Combo (6.3mm jack + XLR) and RCA
Outputs	SPK, 6.3mm jack and 4mm binding posts

Precautions

	CAUTION
	RISK OF ELECTRIC SHOCK DO NOT OPEN
CAUTION : TO REDUCE THE RISK OF ELECTRIC SHOCK, DO NOT REMOVE COVER (OR BACK) NO USER-SERVICEABLE PARTS INSIDE REFER SERVICING TO QUALIFIED SERVICE PERSONNEL

This symbol indicates that dangerous voltage constituting a risk of electric shock is present within this unit

This symbol indicates that there are important operating and maintenance instructions in the literature accompanying this unit

Safety Notice

Prior to use, read through this safety guide.
Pay attention to safety warnings.
Observe all operating requirements.
For any items designed for indoor use only, do not operate near water or in humid environments.
For cleaning, only use a lint-free, dry cloth.
Install according to the specifications.
Place away from heat sources or heating appliances.
During placement, ensure adequate support for the product and access to controls and connectors.
Do not obstruct any cooling vents or openings and allow adequate space for air flow.
Use only power connections supplied with the product or suitable equivalents.
Do not modify the equipment in any way.
For any mains powered appliances, ensure that the mains voltage is as described in the specifications.
Keep powered products and batteries away from the reach of children.
In case of malfunction, water ingress or other damage, consult qualified service personnel.
Avoid pressure or impact to the housing that may result in damage when transporting or installing this product.
For any Earthed mains product, ensure that the power supply has a protective Earth connection.
Keep all packaging materials out of reach of children.

Disposal : The "Crossed Wheelie Bin" symbol on the product means that the product is classed as Electrical or Electronic equipment and should not be disposed with other household or commercial waste at the end of its useful life. The goods must be disposed of according to your local council guidelines.