Boss AC-3 User Manual

Owner’s Manual

DCAC

AC & BATTERY

POWERED

FET

Thank you, and congratulations on your choice of BOSS AC-3 Acoustic Simulator.

Before using this unit, carefully read the sections entitled: “USING THE UNIT SAFELY” and
“IMPORTANT NOTES” (separate sheet). These sections provide important information con­cerning the proper operation of the unit.

Additionally, in order to feel assured that you have gained a good grasp of every feature pro­vided by your new unit, this manual should be read in its entirety. The manual should be
saved and kept on hand as a convenient reference.

A battery is supplied with the unit. The life of this battery may be limited, however, since
its primary purpose was to enable testing.

Copyright © 2006 BOSS CORPORATION

All rights reserved. No part of this publication may be reproduced in any form without the
written permission of BOSS CORPORATION.

2

●

●

●

●

●

Main Features

Effects processor utilizes COSM technology to transform electric guitar input into beautiful
acoustic guitar sounds.

MODE knob allows you to select from a choice of four different acoustic guitar characters
(tones).

Features two types of output jacks, one for guitar amps and another for line out jacks, pro­viding you with outputs suited to the connected device.

“BODY” and “TOP” knobs can be used to adjust the acoustic guitar’s characteristic body
resonance and harmonics, allowing you to produce a wide variety of tones.

Includes high-quality reverb developed exclusively for the AC-3.

COSM (Composite Object Sound Modeling)

Composite Object Sound Modeling (COSM) is BOSS/Roland’s innovative and powerful sound
modeling technology.
COSM analyzes the many factors that make up the original sound, such as the electrical and
physical characteristics of the original, and then produces a digital model that can reproduce
the same sound.

3

Panel Descriptions

fig.01

12

3

4

1. AC Adaptor Jack

Accepts connection of an AC Adaptor (op­tionally available BOSS PSA-series). By using
an AC Adaptor, you can play without being
concerned about how much battery power
you have left.

* If there are batteries in the unit while an AC

adaptor is being used, normal operation will

7

continue should the line voltage be inter­rupted (power blackout or power cord discon­nection).

* Use only the specified AC adaptor (PSA-

series).

5

6

2. CHECK Indicator

This indicator shows whether an effect is
ON/OFF, and also doubles as the Battery
Check indicator. The indicator lights when
an effect is ON.

4

*

If this indicator goes dim or no longer lights
while an effect is ON, the battery is near
exhaustion and should be replaced immedi­ately. For instructions on changing the battery,
refer to

“Changing the Battery” (p. 16)

* The CHECK indicator shows whether the

effect is being applied or not. It does not
indicate whether the power to the device
is on or not.

.

3. LINE OUT Jack

This output jack is used for connecting to
mixers, recorders, and other devices that ac­cept line-level input.
When a cable is also connected to the G.AMP
OUT jack, the output is sent from the LINE
OUT jack when the effect is switched on,
while the output is muted when the effect is
switched off.
For details, see “Connections” (p. 8–p. 13).

Panel Descriptions

4. G.AMP (Guitar Amp) OUT Jack

This output jack is used for connecting to
guitar amps and other effects processors.
The effect sound or direct sound is output
from here depending on whether the effect is
switched on or off.
When a cable is simultaneously connected to
the LINE OUT jack, the output from the
G.AMP OUT jack is muted when the effect is
switched on, while the direct sound is output
when the effect is switched off.
For details, see “Connections” (p. 8–p. 13).

5. Pedal Switch

This switch turns the effects on/off.

5

Panel Descriptions

6. Thumbscrew

When this screw is loosened, the pedal will
open, allowing you to change the battery.

* For instructions on changing the battery,

refer to “Changing the Battery” (p. 16).

7. INPUT Jack

This jack accepts input signals (coming from
a guitar, some other musical instrument, or
another effects unit).

* The INPUT jack doubles as power switch.

Power to the unit is turned on when you plug
into the INPUT jack; the power is turned off
when the cable is unplugged. When not using
the effects unit, be sure to disconnect the plug
from the INPUT jack.

6

fig.02

10

11 12

8 9

8. REVERB Knob

This adjusts the amount of reverb applied to
the sound.

9. LEVEL Knob

This adjusts the volume of the effect sound.

Panel Descriptions

10 . BODY Knob

This adjusts the resonance of the sound pro­duced by the guitar body, altering the char­acteristic mellowness and breadth of the
acoustic guitar sound.

11 . TOP Knob

This adjusts the sense of attack and the har­monic content of the upper range.

12 . MODE Knob

Provides for selection of the tone. The knob can be used to select any of four tones.

STANDARD

JUMBO

ENHANCE

PIEZO

This tone is that of the popular Dreadnought acoustic guitar body style.

This setting provides a tone characteristic of an oversized guitar body,
a tone featuring a rich bass response along with a beautiful high end.

Providing a sharper attack than the standard tone, this tone does not
become masked by the sounds of other instruments, even in bands and
ensembles.

This setting provides the tone of a round-back acoustic guitar,
with subdued body resonance and a unique attack.

7

Connections

* Raise the amp volume only after turning on the

power to all connected devices.

* The use of an AC adaptor is recommended as the

unit’s power consumption is relatively high.
Should you prefer to use batteries, please use the
alkaline type.

* 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.

* If there are batteries in the unit while an AC

adaptor is being used, normal operation will
continue should the line voltage be interrupted
(power blackout or power cord disconnection).

NOTE (Placement)

Depending on the material and temperature of the surface on which you place the unit, its bottom cover (rubber) may
discolor or mar the surface. You can place a piece of felt or cloth under the bottom cover to prevent this from happening.
If you do so, please make sure that the unit will not slip or move accidentally.

8

* Once the connections have been completed, 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.

When powering up:

Turn on the power to your guitar amp last.

When powering down:

Turn off the power to your guitar amp first.

* Always make sure to have the volume level

turned down before switching on power. Even
with the volume all the way down, you may still
hear some sound when the power is switched on,
but this is normal, and does not indicate a
malfunction.

* When operating on battery power only, the

CHECK indicator will become dim when battery
power gets too low. Replace the battery as soon
as possible.

When Connecting to a Guitar Amp

fig.09

OUT 9V DC/200 mA

Guitar Amp Multiple Effects, etc.

Connections

AC Adaptor
BOSS PSA-series
(sold separately)

Electric Guitar

9

Connections

When Connecting to a PA System, Recorder, or Similar Equipment

fig.10

PA System

Recorder

10

AC Adaptor
BOSS PSA-series
(sold separately)

Electric Guitar

■

Connections

When Connecting Both to a Guitar Amp and PA System (or Recorder or Similar Equipment)

With Effect On

The CHECK indicator lights, the output from the AC-3: G.AMP OUT jack is muted, and the
effect sound is output from the LINE OUT jack.

fig.11

PA System

Recorder

Guitar Amp Multiple Effects, etc.

Effect sound

Mute

AC Adaptor
BOSS PSA-series
(sold separately)

Electric Guitar

11

■

Connections

With Effect Off

The CHECK indicator is off, the guitar sound (with effect off) is output from the AC-3: G.AMP
OUT jack, and the output from the LINE OUT jack is muted.

fig.11_02

AC Adaptor
BOSS PSA-series
(sold separately)

PA System

Mute

Recorder

Guitar Amp Multiple Effects, etc.

Guitar sound

(Direct sound)

Electric Guitar

12

Connections

The following shows the correspondence between output jack connection status and the sound
output.

Both LINE OUT
and G.AMP OUT
Connected

Only
LINE OUT
Connected

Only
G.AMP OUT
Connected

Output from LINE OUT

Effects On

Effect Sound

(Line)

Effect Sound

(Line)

- - - - - -

Effects Off Effects On Effects Off

Direct Sound - - - - - -

Output from G.AMP OUT

Mute Mute Direct Sound

Effect Sound

(for Guitar Amp)

Direct Sound

13

Operating the Unit

fig.03

fig.04

fig.05

1.

2.

3.

4.

When you have made the
necessary connections (p.
8–p. 12), set the knobs as
shown in the illustration.

14

Depress the pedal switch
to turn the effect on.
(Make sure that the
CHECK indicator lights.)

Select the mode with the
MODE knob.

Adjust the harmonic con­tent with the TOP knob.

* If the sound is distorted,

adjust by turning the TOP
knob to the left (counter­clockwise).

* Distortion can also be

suppressed by turning the
LEVEL knob to the left.

fig.06

fig.07

fig.08

5.

6.

Operating the Unit

7.

Adjust the breadth of the
sound with the BODY
knob.

Using the LEVEL knob,
adjust the balance of the
volume for when the
effects are on and when
off.

Adjust the amount of
reverb with the REVERB
knob.

15

Changing the Battery

1.

When the indicator goes dim or no longer
lights while an effect is on, it means that the
battery is nearly dead and must be replaced.
Replace the battery following the steps below.

*

The use of an AC adaptor is recommended as the
unit’s power consumption is relatively high. Should
you prefer to use batteries, please use the alkaline type.

fig.12

Thumbscrew

Battery Snap
Cord

Battery
Snap

9V Battery

Battery Housing

Pedal

Spring Base

Coil Spring

Guide Bush
Hole

16

Loosen the thumbscrew at the front of
the pedal, then lift the pedal upwards to
open the unit.

* The thumbscrew can be left in the pedal while

changing the battery.

2. Remove the old battery from the battery

housing, and remove the snap cord con­nected to it.

3. Connect the snap cord to the new battery,

and place the battery inside the battery
housing.

* Be sure to carefully observe the battery’s

polarity (+ versus –).

4. Slip the coil spring onto the spring base

on the back of the pedal, then close the
pedal.

* Carefully avoid getting the snap cord caught in the

pedal, coil spring and battery housing.

5. Finally, insert the thumbscrew into the

guide bush hole and fasten it securely.

Troubleshooting

Power won’t come on /
CHECK indicator doesn’t light:

● Is the specified adaptor (PSA-series;
sold separately) properly connected?

Check the connection once more (p. 8).

* Never use any AC adapter other than one

specified for use with the AC-3.

● Is the battery low or dead?

Replace with a new battery (p. 16).

* The battery that was supplied with the unit is

for temporary use, intended primarily for
testing its operation.

* The use of an AC adaptor is recommended as

the unit's power consumption is relatively
high. Should you prefer to use batteries,
please use the alkaline type.

To prevent unnecessary battery consumption,

*

be sure to disconnect the plug from the INPUT
jack when not using the effects unit (

p. 6

).

● Is your guitar properly connected to the
INPUT jack?

Check the connection once more (p. 8).

* The power is switched on only when a cable is

plugged in to the INPUT jack.

* The CHECK indicator shows whether the

effect is being applied or not. It does not
indicate whether the power to the device is on
or not.

Sound is distorted:

● Is the battery low?

As the battery is drained, the CHECK in­dicator dims, and the AC-3 may start to
function incorrectly. Replace with a new
battery (p. 16).

17

Setting Samples

Finger Picking
(Single coil, front pickup)

fig.13-1

Chord Stroke
(Single coil, front pickup)

fig.13-2

18

Solo Phrase
(Single coil, front pickup)

fig.13-3

Humbucking Setting
(Humbucking, front pickup)

fig.13-4

Setting Memo

fig.14

fig.14

fig.14

fig.14

19

Setting Memo

fig.14

fig.14

20

fig.14

fig.14

Specifications

AC-3: Acoustic Simulator

Nominal Input Level..................... -20 dBu

Input Impedance............................ 1 MΩ

Nominal Output Level.................. -20 dBu

Output Impedance ........................ 1 kΩ

Recommended Load Impedance

Controls........................................... Pedal switch, LEVEL knob, REVERB knob, BODY knob,

Indicators ........................................ CHECK indicator (Serves also as battery check indicator)

Connectors...................................... INPUT jack, LINE OUT jack, G.AMP OUT jack,

Power Supply................................. DC 9 V:

...... 10 kΩ or greater

TOP knob, MODE knob

AC adaptor jack (DC 9 V)

Dry battery/9 V type (6F22 (carbon), 6LR61 (alkaline))

AC Adaptor (PSA-series: optional)

,

21

Specifications

Current Draw ................................. 39 mA (DC 9 V)

* Expected battery life under continuous use:

Carbon: 3 hours, Alkaline: 10 hours
These figures will vary depending on the actual conditions of use.

Dimensions..................................... 73 (W) x 129 (D) x 59 (H) mm

2-7/8 (W) x 5-1/8 (D) x 2-3/8 (H) inches

Weight ............................................. 440 g /1 lb (including battery)

Accessories...................................... Owner’s Manual, Leaflet (“USING THE UNIT SAFELY,”

“IMPORTANT NOTES,” and “Information”),
Dry battery/9 V type (6LR61)

* The battery that was supplied with the unit is for temporary use-

intended primarily for testing its operation.
We also suggest replacing this with an alkaline dry cell.

Option ............................................. AC Adaptor (PSA-series)

*0 dBu = 0.775 Vrms

* In the interest of product improvement, the specifications and/or appearance of this unit are subject to change

without prior notice.

22

For EU Countries

This product complies with the requirements of European Directive 89/336/EEC.

For the USA

FEDERAL COMMUNICATIONS COMMISSION

RADIO FREQUENCY INTERFERENCE STATEMENT

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the
FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential
installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in
accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee
that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or
television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the
interference by one or more of the following measures:

– Reorient or relocate the receiving antenna.
– Increase the separation between the equipment and receiver.
– Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
– Consult the dealer or an experienced radio/TV technician for help.

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and
(2) This device must accept any interference received, including interference that may cause undesired operation.

Unauthorized changes or modification to this system can void the users authority to operate this equipment.
This equipment requires shielded interface cables in order to meet FCC class B Limit.

For Canada

NOTICE

This Class B digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations.

Cet appareil numérique de la classe B respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada.

AVIS

G6027114R1