A1 Four

Multi-Effects Processor for Acoustic Instruments
The Zoom A1 FOUR is designed specifically for acoustic guitars, wind, and string instruments, offering tailored effects that preserve natural tone while expanding creative options.

Over 80 Built-In Effects
Includes distortion, chorus, wah, and more, plus over 35 effects newly engineered for acoustic instruments like saxophone, violin, harmonica, trumpet, and upright bass.

5 Effects at Once
Chain up to 5 effects in any order to shape your sound exactly how you want.

Acoustic Guitar Modeling
Use IR-based modeling to recreate the sound character of iconic guitar body shapes with adjustable parameters for gain, bass, mid, and treble.

Instrument-Specific Presets
Choose from ready-to-use patches tailored for acoustic guitar, sax, trumpet, violin, harmonica, and more.

Built-In Looper
Record up to 30 seconds of CD-quality audio to layer and build dynamic arrangements on the fly.

Rhythm and Drums Included
Play along with 68 built-in rhythm patterns, including jazz, samba, and reggae styles.

Anti-Feedback Filter
Automatically detects and cuts feedback frequencies to keep your tone clean in live settings.

Stomp and Memory Modes
Switch between individual effect control or preset patch changes with your foot.

USB and Software Integration
Connect to Zoom Guitar Lab via USB to edit effects, download patches, and expand your library.

Mic Support with MAA-1 Adapter
Included MAA-1 mic adapter allows use with dynamic or condenser mics and adds gain control and phantom power.

Battery or USB Powered
Runs on 4 AA batteries (up to 18 hours) or USB for flexible power options.

Compact and Lightweight
Portable design fits easily into any setup, weighing just 340g (excluding batteries).

General Specifications
Device Type: Multi-Effects Processor for Acoustic Instruments
Compatible Instruments: Acoustic Guitar, Saxophone, Trumpet, Violin, Harmonica, Acoustic Bass, and more
Number of Built-In Effects: Over 80
Maximum Simultaneous Effects: 5
Patch Memory: 50 User Patches
Looper: Yes, up to 30 seconds / 64 beats (CD-quality audio)
Drum Machine: 68 Built-In Rhythm Patterns
Tuner: Onboard Chromatic Tuner (supports standard, open, and drop tunings)
Display: 128 × 32 Dot Matrix LCD
Control Modes: MEMORY Mode, STOMP Mode

Effect Processing
Sampling Frequency: 44.1 kHz
A/D Conversion: 24-bit, 128× Oversampling
D/A Conversion: 24-bit, 128× Oversampling
Signal Processing: 32-bit
IR Modeling: Acoustic Guitar Body Models with Adjustable Parameters (Gain, Bass, Mid, Treble)
Pickup Selector: Piezo / Magnetic with EQ Matching
Anti-Feedback Filter: Built-In
Guitar Lab Software: Supported (Effect and Patch Management via USB)
Unique Instrument Effects:
– Sax: SaxChorus, Revoiced Wah with LPF
– Trumpet: Tp MD70 Preset, Custom Wah Voicing
– Violin: Vn DIST Effect with Shifted Clipping and EQ
– Harmonica: Hm StevieW and Hm Juke Presets, Bullet Mic Simulation
– Upright Bass: Custom EQ, Octave, and Piezo Simulation Options

Input/Output
Instrument Input: Standard Mono Phone Jack
Input Level: -20 dBu
Input Impedance: 470 kΩ
Aux Input: Stereo Mini Jack
Aux Input Level: -10 dBu
Aux Input Impedance: 1 kΩ
Output: Standard Stereo Phone Jack (Line/Headphone Combined)
Maximum Line Output Level: +2 dBu (10 kΩ or more output impedance)
Headphone Output: 17 mW + 17 mW (32 Ω Load)
Input Signal-to-Noise Ratio: 120 dB
Residual Noise (Noise Floor): -97 dBu

Power
Power Options:
– 4 AA Batteries (Alkaline, up to 18 hours with LCD backlight off)
– USB Bus Power (USB Micro-B, power-only cable disables data functions)
– Optional AC Adapter: 9V DC 500 mA, Center Negative (ZOOM AD-16)

USB
USB Functions: USB MIDI, Power Supply, Firmware Updates, Guitar Lab Connectivity
USB Connector: USB Micro-B

Dimensions & Weight
External Dimensions (A1 FOUR): 156 mm (D) × 130 mm (W) × 42 mm (H)
Weight (A1 FOUR): 340 g (excluding batteries)

Included Accessories
Multi-Effects Processor: A1 FOUR
Mic Adapter: MAA-1
Quick Guide: 1x
Patch List: 1x