Roland ac-90 Owner's Manual

291b

301

• Do not connect this unit to same electrical outlet that is being 

used by an electrical appliance that is controlled by an inverter 
(such as a refrigerator, washing machine, microwave oven, or air 
conditioner), or that contains a motor. Depending on the way in 
which the electrical appliance is used, power supply noise may 
cause this unit to malfunction or may produce audible noise. If it 
is not practical to use a separate electrical outlet, connect a power 
supply noise filter between this unit and the electrical outlet.

307

• Before connecting this unit to other devices, turn off the power to 

all units. This will help prevent malfunctions and/or damage to 
speakers or other devices.

308

• Although the LEDs are switched off when the POWER switch is 

switched off, this does not mean that the unit has been completely 
disconnected from the source of power. If you need to turn off the 
power completely, first turn off the POWER switch, then unplug 
the power cord from the power outlet. For this reason, the outlet 
into which you choose to connect the power cord’s plug should 
be one that is within easy reach and readily accessible.

351

• Using the unit near power amplifiers (or other equipment 

containing large power transformers) may induce hum. To 
alleviate the problem, change the orientation of this unit; or move 
it farther away from the source of interference.

352a

• This device may interfere with radio and television reception. Do 

not use this device in the vicinity of such receivers.

352b

• Noise may be produced if wireless communications devices, such 

as cell phones, are operated in the vicinity of this unit. Such noise 
could occur when receiving or initiating a call, or while 
conversing. Should you experience such problems, you should 
relocate such wireless devices so they are at a greater distance 
from this unit, or switch them off.

354b

• Do not expose the unit to direct sunlight, place it near devices 

that radiate heat, leave it inside an enclosed vehicle, or otherwise 
subject it to temperature extremes. Also, do not allow lighting 
devices that normally are used while their light source is very 
close to the unit (such as a piano light), or powerful spotlights to 
shine upon the same area of the unit for extended periods of time. 
Excessive heat can deform or discolor the unit.

355b

• When moved from one location to another where the temperature 

and/or humidity is very different, water droplets (condensation) 
may form inside the unit. Damage or malfunction may result if 
you attempt to use the unit in this condition. Therefore, before 
using the unit, you must allow it to stand for several hours, until 
the condensation has completely evaporated.

356

• Do not allow rubber, vinyl, or similar materials to remain on the 

unit for long periods of time. Such objects can discolor or 
otherwise harmfully affect the finish.

359

• Do not paste stickers, decals, or the like to this instrument. 

Peeling such matter off the instrument may damage the exterior 
finish.

360

• Depending on the material and temperature of the surface on 

which you place the unit, its rubber feet may discolor or mar the 
surface.
You can place a piece of felt or cloth under the rubber feet to 
prevent this from happening. If you do so, please make sure that 
the unit will not slip or move accidentally.

Add

• Do not allow objects to remain on top of the unit while it is in 

operation.

• Do not sit or lean on top of the unit.

401a

• For everyday cleaning wipe the unit with a soft, dry cloth or one 

that has been slightly dampened with water. To remove stubborn 
dirt, use a cloth impregnated with a mild, non-abrasive detergent. 
Afterwards, be sure to wipe the unit thoroughly with a soft, dry 
cloth.

402

• Never use benzine, thinners, alcohol or solvents of any kind, to 

avoid the possibility of discoloration and/or deformation.

553

• Use a reasonable amount of care when using the unit’s buttons, 

sliders, or other controls; and when using its jacks and 
connectors. Rough handling can lead to malfunctions.

556

• When connecting / disconnecting all cables, grasp the connector 

itself—never pull on the cable. This way you will avoid causing 
shorts, or damage to the cable’s internal elements.

557

• A small amount of heat will radiate from the unit during normal 

operation.

558a

• To avoid disturbing your neighbors, try to keep the unit’s volume 

at reasonable levels. You may prefer to use headphones, so you 
do not need to be concerned about those around you (especially 
when it is late at night).

559a

• When you need to transport the unit, package it in the box 

(including padding) that it came in, if possible. Otherwise, you 
will need to use equivalent packaging materials.

562

• Some connection cables contain resistors. Do not use cables that 

incorporate resistors for connecting to this unit. The use of such 
cables can cause the sound level to be extremely low, or impos-
sible to hear. For information on cable specifications, contact the 
manufacturer of the cable.

921

• To prevent malfunction and/or damage to speakers or other 

devices, always turn down the volume, and turn off the power on 
all devices before making any connections.

922

• This instrument is equipped with balanced XLR/TRS type jacks. 

Wiring diagrams for these jacks are shown below. Make connec-
tions after first checking the wiring diagrams of other equipment 
you intend to connect.

fig.XLR/TRSJack.eps

941

• Once the connections have been completed (p. 11), turn on power 

to your various devices in the order specified. By turning on 
devices in the wrong order, you risk causing malfunction and/or 
damage to speakers and other devices.

Turn on the power to the AC-90 last.

Turn off the power to the AC-90 first.

Add

• Wrap the AC cord around the cord hook when trans-porting or 

storing the unit.

AC-90_egfispd.book  Page 5  Tuesday, August 14, 2007  10:09 AM