Ideal for gigging guitarists and singer/songwriters, the versatile AC-40 delivers top-quality stereo acoustic amplification in an affordable, mobile package. The latest addition to Roland’s trusted Acoustic Chorus family features clean, loud, and natural sound reproduction for acoustic instruments, with a dual-channel configuration that supports both a guitar and a microphone. Onboard stereo effects include a high-quality digital reverb and Roland’s famous chorus, while the anti-feedback function automatically controls problematic acoustic feedback, allowing you to play and sing with no worries. Lightweight, rugged, and performance-ready, the AC-40 is the perfect solution for acoustic musicians on the move.



  • Powerful and lightweight stereo amplifier with natural acoustic tone
  • Dual custom-designed 6.5-inch speakers deliver impressive sound levels with superior projection
  • Stereo chorus and reverb effects for rich, spacious sound
  • Dual channels: GUITAR (1/4-inch input) and MIC/LINE (XLR/TRS input), each with three-band EQ and independent effects controls
  • AUX IN with level control for connecting music players
  • Mono/stereo LINE OUT for interfacing with house sound systems and recording devices
  • Automatic anti-feedback function

Natural Acoustic Tone, Enhanced with Stereo Effects

The AC-40 carries on the tradition of Roland’s acclaimed Acoustic Chorus series, delivering pure and natural sound amplification for acoustic guitars, vocal mics, and other acoustic instruments. Like the entire AC line, it features true stereo output with dual speakers plus built-in stereo chorus and reverb effects, providing studio-quality depth and dimension that’s not possible with mono amps.

Dual-Channel Flexibility

With its two independent channels, the AC-40 gives you pro versatility for any performing setup. There’s a dedicated GUITAR channel with a standard 1/4-inch input, plus a MIC/LINE channel with an XLR/TRS combo input for connecting a microphone or a line-level device. Plug in a guitar and a mic for self-contained playing and singing, or use the channels to mix two types of pickups (or a pickup and a mic) in more sophisticated guitar rigs. Each channel has its own three-band EQ for sound shaping plus independent chorus and reverb controls, giving you complete command over your sound.

Essential Performance Extras

The AC-40’s rear panel offers a number of connectivity options for a variety of situations. Connect an external music player to the stereo AUX IN for backing tracks and practice, and use the dedicated level control to balance the sound. Mono/stereo LINE OUT jacks give you the ability to connect to PA systems when performing in larger venues, or to recording devices to capture natural sound along with the amp’s rich stereo effects. Plugging into the PHONES jack mutes the internal speakers, letting you practice without disturbing others. A jack is also provided for turning the reverb and chorus effects on/off with optional footswitches.

Big Sound, Compact Size

Ultra-compact and weighing under 12 pounds (5.3 kg), the AC-40 is a breeze to carry wherever you want to play. Though small in size, it has a big sound that easily carries your performance in venues such as intimate nightclubs, restaurants, and coffee houses. Thanks to the integrated tilt-back stand, it’s simple to angle the amp for more projection when placed on the floor or another flat surface. The AC-40 is also ideal as a personal monitor when performing on larger stages.


As every live performer knows, acoustic feedback can sometimes be a problem on stage, especially in situations when you need to push the volume or when you’re playing in confined spaces. The AC-40’s anti-feedback function has got you covered, automatically suppressing feedback before it causes trouble. With the simple flip of a switch, you have the freedom to relax and concentrate on performing without worrying about unexpected sound hassles.


                    Rated Power Output

                    35 W (17.5 W + 17.5 W)

                    Nominal Input Level (1 kHz)

                    GUITAR CHANNEL: -10 dBu
                    MIC/LINE CHANNEL: -50 dBu/-20 dBu
                    AUX IN: -10 dBu

                    Nominal Output Level (1 kHz)

                    LINE OUT: -10 dBu


                    16 cm (6.5 inches) x 2


                    [GUITAR CHANNEL]
                    VOLUME knob
                    BASS knob
                    MIDDLE knob
                    TREBLE knob
                    CHORUS switch (OFF, SPACE, WIDE)
                    REVERB knob

                    [MIC/LINE CHANNEL]
                    VOLUME knob
                    BASS knob
                    MIDDLE knob
                    TREBLE knob
                    CHORUS switch (OFF, SPACE, WIDE)
                    REVERB knob

                    ON/OFF switch

                    [AUX IN]
                    LEVEL knob

                    MASTER knob
                    POWER switch




                    GUITAR CHANNEL INPUT jack: 1/4″ phone type
                    MIC/LINE CHANNEL INPUT jack: XLR type, 1/4″ TRS phone type
                    AUX IN jack: Stereo miniature phone type
                    LINE OUT (L/MONO, R) jacks: 1/4″ phone type
                    PHONES jack: Stereo miniature phone type
                    FOOT SW jack: 1/4″ TRS phone type
                    DC IN jack

                    Power Supply

                    AC Adaptor

                    Current Draw

                    480 mA


                    Owner’s Manual
                    AC Adaptor
                    Power Cord

                    Options (sold separately)

                    Footswitch: BOSS FS-5U, Dual Footswitch: BOSS FS-6, BOSS FS-7
                    Connection Cable: PCS-31L

                    SIZE AND WEIGHT


                    362 mm
                    14-5/16 inches


                    241 mm
                    9-1/2 inches


                    265 mm
                    10-7/16 inches


                    5.3 kg
                    11 lbs. 11 oz.

                    PERFECT SOUND

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