BOSS - EX-4 | Effects Expander

A New Dimension to Your Board

Take your creative vision to the next level with the EX-4, an innovative BOSS effects unit that expands the range of your pedalboard—without changing what already works. This compact inspiration machine complements your current setup with new sound-shaping options and real-time performance tools, encouraging you to explore fresh textures with the rig you already love.

Introduction Video

Highlights

Compact effects processor that expands the capabilities of any pedalboard
120 premium BOSS effects, including overdrives/distortions, mod effects, delays, reverbs, and more
Run up to four effects at once, including multiple instances of the same effect
Dedicated utility blocks, including foot volume, two noise suppressors, send/return, and divider/mixer
Fluid operation with an informative color display, intuitive knobs, and dedicated FX buttons
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
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
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, Minimal Size

Modern players carefully curate their pedalboard builds, and every slot must earn its place. The EX-4 more than carries its weight, delivering a vast library of historic BOSS effects in a modest footprint. It’s the ideal utility pedal for musicians who love to experiment with effects, and an essential tool for stage players who cover many songs/styles and studio musicians who need to build professional sounds when the clock is ticking.

Your Creative Launchpad

With up to four simultaneous effects and flexible connectivity to integrate with everything on your board, the EX-4 has what you need to elevate your core sound with a universe of tonal possibilities. The interface is designed for immediate results, providing a fluid platform to dial up inspiring tones without endless tweaking.

Effects to the Max

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 foot volume and other dedicated utility blocks that can be placed anywhere within an effect chain, plus a global EQ for overall sound shaping.

Build Sounds Fast with Gear Suite

The EX-4’s Gear Suite feature enables lightning-fast tone creation with ready-to-go sounds. Each effect type has multiple Gear Suite settings with professionally tuned parameters, all available with the turn of a knob. Better still, you can edit effect parameters and save your favorites for instant access to custom settings for every effect.

Free-Flowing Interface

A 2.4-inch color display gives you a clear, inviting view of the full signal chain, individual effect blocks, editing options, menus, and more. With dedicated FX buttons, you can turn effect blocks on/off with a single press and access editing parameters with a long press. Button colors dynamically change to match the display's effect colors, making navigation frustration-free.

Dual Footswitches with Split LEDs

Rugged dual-function footswitches can be custom-configured to suit your performance needs, with assignments that include effect block on/off, memory up/down, master bypass, tap tempo, individual parameter control, and more. A newly designed color LED system surrounds the footswitches, making it easy to identify the current footswitch functions as you perform.

Connect and Create

Four audio jacks support mono or stereo connectivity, with the option to use two jacks as an effect loop to place external pedals anywhere in the EX-4's effect chain for complex sound configurations. 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.

Product Gallery

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
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
Size and Weight
Width: 117 mm
4-5/8 inches
Depth: 138 mm
5-7/16 inches
Height: (without rubber feet)
63 mm
2-1/2 inches

(including rubber feet)
65 mm
2-9/16 inches
Weight: 800g
1 lb 13 oz
*0 dBu = 0.775 Vrms

Downloads

Support

If you have questions about operating your BOSS product, please check our Knowledge Base for answers to the most common questions.
You can also contact our Product Support department by phone or email.
In addition, we have a library of Owner’s Manuals and Support Documents that you can download and reference.