Cautionary Notes; Specications - Roland AC-90 Service Notes

Jul. 2007

Cautionary Notes

Before beginning the procedure, please read
through this document. The matters described may
differ according to the model.
No User Data
This product cannot save user data. Backing up user data during servicing is
not required.
Part Replacement
When replacing components near the power-supply circuit or a heat-
generating circuit (such as a circuit provided with a heat sink or including a
cement resistor), carry out the procedure according to the instructions with
respect to the part number, direction, and attachment position (mounting so as
to leave an air gap between the component and the circuit board, etc.).
Parts List
A component whose part code is ******** cannot be supplied as a service part
because one of the following reasons applies.
• Because it is supplied as an assembled part (under a different part code).
• Because a number of circuit boards are grouped together and supplied as
a single circuit board (under a different part code).
• Because supply is prohibited due to copyright restrictions.
• Because reissuance is restricted.
• Because the part is made to order (at current market price).
Circuit Diagram
In the circuit diagram, "NIU" is an abbreviation for "NOT IN USE." The circuit
board and circuit-board diagram show silkscreened indications, but no
components are mounted.
2

Specications

AC-90:Acoustic Chorus
● Rated Power Output
45W + 45W
● Nominal Input Level (1 kHz)
GUITAR Channel: -10 dBu
MIC/LINE Channel: -50/-10 dBu
AUX IN: -10 dBu
● Nominal Output Level (1 kHz)
DI/TUNER OUT: +4 dBu
LINE OUT: +4 dBu
SUB WOOFER OUT: +4 dBu
* 0 dBu = 0.775 Vrms
● Speakers
Woofer 20 cm (8 inches) x 2
Tweeter 8 cm x 5 cm (3 inches x 2 inches) x 2
● Controls
GUITAR Channe l
PICKUP Switch (PIEZO/MAGNETIC)
SHAPE Switch
VOLUME Knob
Equalizer Knobs (BASS, MIDDLE, TREBLE)
CHORUS Switch
MIC/LINE Channel
PHANTOM Switch
SELECT Switch (MIC/LINE)
VOLUME Knob
Equalizer Knobs (BASS, MIDDLE, TREBLE)
CHORUS Switch
CHORUS Knob
REVERB/DELAY Knob
ANTI-FEEDBACK
FREQUENCY Knob
START Button
MUTE Switch
MASTER Knob
POWER Switch
● Indicator
CHORUS (GUITAR Channel, MIC/LINE Channel)
ANTI-FEEDBACK
MUTE
POWER
● Connectors
GUITAR Input Jack (1/4 inch TRS phone type)
MIC/LINE Input Jack (XLR type, 1/4 inch TRS phone type)
AUX IN Jacks (RCA phono type, 1/4 inch phone type)
DI/TUNER OUT Jack (1/4 inch TRS phone type)
LINE OUT Jacks (XLR type, 1/4 inch phone type)
SUB WOOFER OUT Jack (1/4 inch phone type)
PHONES Jack (1/4 inch stereo phone type)
FOOT SWITCH Jack (1/4 inch TRS phone type)
● Power Supply AC
117 V, AC 230 V, AC 240 V (50/60 Hz)
● Power Consumption
30 W
● Dimensions
464 (W) x 303 (D) x 326 (H) mm
18-5/16 (W) x 11-15/16 (D) x 12-7/8 (H)
inches
● Weight
11.7 kg
25 lbs 13 oz
AC-90