Alesis RA150 Manuel D’Utilisation

RA150/300/500 Reference Manual

Introduction ...................................................... 2

How to Use This Manual........................... 2

Instructions de Sécurité Importantes (French) ...... 4
Beim Benutzen dieses Produktes beachten Sie
bitte die folgenden Sicherheitshinweise:
(German) .......................................................... 5
CE Declaration of Conformity............................. 6

Principal Features .............................................. 7

The Chassis .............................................. 7
Inputs and Outputs................................... 7
Amplifier topology ................................... 7
Protection Circuitry .................................. 7

About this manual ............................................. 8

Unpacking and Inspection.................................. 9
Power Considerations ........................................ 9

The AC Cord and Grounding .................... 9
120 Volt/230 Volt Operation.................... 10
Fuse....................................................... 10
Electrical Service to the RA150/300/500... 10

Operating Environment ................................... 11

Temperature Considerations in Rack
Mounting............................................... 11
Other Rack Mounting Tips ...................... 11
Mounting on a Shelf or in a Non-Rack
Enclosure ............................................... 12
Avoiding Electromagnetic Interference .... 12

Inputs ............................................................. 13

Input Jack Characteristics ........................ 13
Cables.................................................... 15
Cable Wiring Tips................................... 15
Balanced or Unbalanced? ........................ 16

Outputs .......................................................... 18

What's the Load Impedance? ................... 18

Connectors..............................................18
Speaker Cables........................................18
Connecting Speaker Cables to Binding
Posts.......................................................19
The Importance of Speaker Polarity ..........20
Output Connections for Bridged
Operation ...............................................20

Front Panel Controls.........................................21

Volume Controls .....................................21
On-Off Switch .........................................21
Mute Switch............................................21
Protect/Clip Indicators............................22
Meters (RA300 and RA500 only)...............22

Back Panel Controls..........................................22

AC Voltage Switch ..................................22
Stereo/Bridged Mono Switch...................22

Checking For Proper Polarity ............................22
Using the RA150 as a Headphone Amplifier.......23
Choosing the Correct Speakers..........................23
About Ground Loops........................................24
System Setup and Testing .................................25

Setting the Gain Properly.........................25
Output Relays/Thermal Cycling ..............26

Troubleshooting Index......................................27
Care and Maintenance ......................................28

Cleaning .................................................28
Refer All Servicing to Alesis .....................28
Obtaining Repair Service .........................29
Customers outside the USA and
Canada: ..................................................29