BOSS EX-4 Effects Expander

A New Dimension to Your Board

The EX-4 is a premium BOSS effects unit that instantly expands the range of any pedalboard, delivering a massive boost of creative firepower in one streamlined stompbox. Craft new sonic universes with up to four simultaneous effects from a vast library, accessed with a simple user interface, flexible footswitches, and a versatile array of connectivity.

FEATURES

• Ultra-compact effects processor that expands the capabilities of any pedalboard

• 120 premium BOSS effects, including overdrives/distortions, mod effects, delays, reverbs, and more

• Dedicated utility blocks, including foot volume, two noise suppressors, send/return, and divider/mixer

• Independent global EQ for overall sound shaping

• Gear Suite feature allows you to quickly configure each effect with the turn of a knob

• Control effects using dual multi-function footswitches with color LEDs

• Versatile mono/stereo I/O, flexible effect loop, and space-saving TRS MIDI jacks   

• Fluid operation with an informative color display, intuitive knobs, and dedicated FX buttons 

• Manual and Memory modes for stompbox-style or preset-based effect control

• 128 preset memories for guitar and bass, plus 128 user memories for saving custom sounds

• Run up to four effects at once, including multiple instances of the same effect

• Create complex effect configurations with advanced series, parallel, and wet/dry options

• Use the effect loop to build reorderable chains with external pedals

• Seamless memory changes with full carryover of delay and reverb effects possible with certain effect configurations

• Use the footswitches for basic effect and preset control, or access deeper assignment features for sophisticated custom operation

Expanded Range, Small Footprint
Modern players carefully curate their pedalboards, and every slot must earn its place. Offering a large selection of classic BOSS effects in a space-saving package, there’s no better utility pedal than the EX-4. It’s ideal for musicians who love to experiment with effects, and an essential toolbox for anyone who needs to cover many songs/styles or build professional sounds on the fly.

A Library of Premium BOSS Effects
Every major category is available among the 120 effect selections in the EX-4, including overdrive and distortion, modulation, delay, and reverb, as well as bass-tuned effects and unique BOSS favorites like Slow Gear and Slicer. You also get dedicated utility blocks that can be placed anywhere within an effect chain—including foot volume, two noise suppressors, send/return, and divider/mixer—plus a global EQ for overall sound shaping.

Speedy Sound Creation with Gear Suite
The EX-4’s Gear Suite feature makes it quick and easy to call up ready-to-go sounds. Each effect type comes with multiple pre-made Gear Suite settings with professionally tuned parameters, all available with the turn of a knob. It’s also possible to edit effect parameters and save favorites in user locations for instant access to personalized setups.

Fluid Interface with Dedicated FX Buttons
A full color 2.4-inch display provides clear viewing of the full effect signal chain, individual effect blocks, editing options, menus, and more. Quickly turn effect blocks on/off with a single press and access editing parameters with a long press. FX button colors match each effect's display colors for fast identification.
Dual Footswitches with Split LEDs

Rugged dual-function footswitches can be custom-configured system-wide or per memory, with assignments that include effect block on/off, memory up/down, master bypass, tap tempo, and more. A newly designed color LED system surrounds the footswitches, allowing you to clearly identify current footswitch functions while performing.  
Comprehensive Connectivity

Four audio jacks provide mono or stereo connectivity, with the option to use two jacks as an effect loop to place external pedals anywhere within the EX-4's effect chain. Two footswitches or an expression pedal can be connected for more real-time control, while space-saving TRS MIDI I/O unlocks deep integration with other MIDI pedals, switching systems, and external clocking devices.

SPECIFICATIONS

Sampling Frequency: 48 kHz

AD Conversion: 24 bits + AF method
*AF method (Adaptive Focus method) This is a proprietary method from Roland & BOSS that vastly improves the signal-to-noise (SN) ratio of the AD and DA converters.

DA Conversion: 32 bits
Processing: 32-bit floating point
Effects: 120 types
Maximum Number of Effects:

• 4(FX1-4) + 6(DIVIDER+MIXER, SEND RETURN, FOOT VOLUME, NOISE SUPPRESSOR1, NOISE SUPPRESSOR2, GLOBAL EQ)

Memories: 128 (User) + 128 (Preset)

Nominal Input Level
INPUT L/MONO jack, INPUT R(RETURN) jack: -10 dBu

Maximum Input Level
INPUT L/MONO jack, INPUT R(RETURN) jack: +7 dBu

Input Impedance
INPUT L/MONO jack, INPUT R(RETURN) jack: 1 M ohm

Nominal Output Level
OUTPUT L/MONO jack, OUTPUT R(SEND) jack: -10 dBu

Output Impedance
OUTPUT L/MONO jack, OUTPUT R(SEND) jack: 1 k ohm

Recommended Load Impedance
OUTPUT L/MONO jack, OUTPUT R(SEND) jack: 10 k ohms or greater

Controls:

• DOWN/1 switch, UP/2 switch, 

• MENU/EXIT button, GEAR SUITE button, FX1 button, FX2 button, FX3 button, FX4 button,

• SELECT knob, TYPE/VALUE knob, 1-3 knobs

Display: Color Graphic LCD (320 x 240 dots)

Connectors:

• INPUT L/MONO jack, INPUT R(RETURN) jack, OUTPUT L/MONO jack, OUTPUT R(SEND) jack, : 1/4-inch phone type

• MIDI IN jack, MIDI OUT jack : Miniature phone type

• CTL1([3]),2([4])/EXP jack: 1/4-inch TRS phone type

• USB port: USB Type-C(R)

• DC IN jack

Power Supply: AC adaptor (PSA-S series)
Current Draw: 300 mA

Dimensions (without rubber feet): 117 (W) x 138 (D) x 63 (H) mm / 4-5/8 (W) x 5-7/16 (D) x 2-1/2 (H) inches
Dimensions (including rubber feet): 117 (W) x 138 (D) x 65 (H) mm / 4-5/8 (W) x 5-7/16 (D) x 2-9/16 (H) inches
Weight: 800g / 1 lb 13 oz

Accessories:

• STARTUP GUIDE

• Leaflet "Read Me First"

• AC adaptor: PSA-S series

• Rubber foot x 4

Options (sold separately)
Footswitch: FS-5U, FS-5L, FS-6, FS-7
Expression Pedal: FV-500L, FV-500H, EV-30, Roland EV-5
TRS/MIDI connecting cable: BMIDI-5-35, BMIDI-1-35, BMIDI-2-35, BCC-1-3535, BCC-2-3535

*0 dBu = 0.775 Vrms

For more information, click here to visit the manufacturers website.