Boss EX-4 Effects Expander Multi-FX Pedal

The Boss EX-4 Effects Expander is a compact multi-FX unit designed to supercharge your pedalboard without taking up much space. Run up to four effects at once from a huge library of classic Boss sounds, giving you access to everything from everyday essentials to more adventurous textures. It's a doddle to use too, thanks to an intuitive interface that's quick to get your head around.

Big tones, small footprint

If you're constantly battling for space on your board, the EX-4 could be the ultimate utility pedal to streamline your setup. It packs a massive collection of effects into a dinky enclosure, making it perfect for cover band players, session musicians or anyone who needs maximum flexibility without carrying a suitcase full of stompboxes.

120 classic Boss effects

With 120 effects onboard, you've got everything from overdrive, modulation, delay and reverb to niche Boss favourites like Slow Gear and Slicer — plus a selection of bass-tuned FX. You also get a range of utility blocks that can be placed anywhere in the signal chain, including foot volume, dual noise suppressors, send/return, divider/mixer and a global EQ for fine-tuning your overall sound.

Build great sounds fast with Gear Suite

The EX-4's Gear Suite feature makes it quick and easy to call up inspiring sounds in seconds. Each effect type includes a multiple professionally dialled-in settings that are ready to use straight away, all available with the turn of a knob. Once you've found your perfect setup, you can tweak parameters and save your favourite sounds for instant recall later.

Built for the stage

A bright colour display, dedicated FX buttons and customisable dual-function footswitches make the EX-4 really straightforward to use, whether you're rehearsing at home or playing a packed-out venue. Add stereo operation, an assignable effects loop, expression pedal support and MIDI connectivity, and you've got a seriously powerful effects hub that can slot seamlessly into almost any rig.

• Ultra-compact effects processor: Designed to expand the capabilities of any pedalboard without taking up much space.
• 120 premium Boss FX: Including overdrives, distortions, modulation effects, delays, reverbs and more.
• Dedicated utility blocks: Such as foot volume, two noise suppressors, send/return and a divider/mixer — all of which can be placed anywhere within an effect chain.
• Gear Suite feature: Lets you quickly configure each effect with the turn of a knob.
• Easy on-the-fly control: You can manipulate effects using dual multi-function footswitches with colour LEDs. Use them for basic effect and preset control or access deeper assignment features for sophisticated custom operation.
• Slots into any rig: Thanks to versatile mono/stereo I/O, a flexible built-in effect loop and space-saving TRS MIDI jacks.
• Fluid operation: With its informative 2.4-inch colour display, intuitive knobs and dedicated FX buttons, you’ll be getting the most out of the EX-4 in no time!
• Manual and Memory modes: For stompbox-style or preset-based effect control.
• Plenty of storage: Includes 128 preset memories for guitar and bass, plus 128 user memories for saving custom sounds.
• Run up to four effects at once: Build big chains, including multiple instances of the same effect.
• Create complex effect configurations: With advanced series, parallel and wet/dry options.
• Built-in effect loop: Use this to build reorderable chains with your favourite external pedals.
• Seamless memory changes: With full carryover of delay and reverb effects possible with certain effect configurations.

General

• Sampling Frequency: 48 kHz
• AD Conversion: 24 bits + AF method
• 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 Suppressor 1, Noise Suppressor 2, Global EQ)
• Memories: 128 (User) + 128 (Preset)
• 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: Colour Graphic LCD (320 x 240 dots)

Connectors

• Input L/Mono jack, Input R (Return) jack, Ouput L/Mono jack, Output R (Send) jack
• MIDI In jack, MIDI Out jack
• CTL1([3]), 2([4])/EXP jack
• USB port (USB Type-C)
• DC IN jack

Power requirements

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

Dimensions & weight

• Dimensions (W x D x H) 117 x 138 x 63 mm / 4.625 x 5.4375 x 2.5 inches
• Weight: 800 g / 1 lb 13 oz

Included items

• Startup guide
• "Read Me First" leaflet
• 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