Boss EX-4 Effects Expander

Four Boss Pedals Living in One Box

The Boss EX-4 is a compact stereo multi-effects unit built to expand an existing pedalboard rather than replace the whole rig. It holds 120 effects and can run four at once, including multiple copies of the same sound for parallel delays or more unusual stacks.

Classics, Rarities and Quick Starting Points

Its library covers overdrive, distortion, modulation, delay and reverb, plus bass-focused effects and less common Boss favorites such as Slow Gear and Slicer. Gear Suite supplies ready-made settings for each effect type, giving players a usable starting point before they tweak and save their own version.

Stompbox Control or Complete Presets

Manual mode treats the four effect slots like individual pedals, while Memory mode changes whole presets and can preserve delay or reverb trails in supported setups. The EX-4 stores 128 user memories alongside 128 factory presets. A 2.4-inch color screen, four dedicated effect buttons and physical parameter knobs keep common edits on the hardware.

Flexible Routing Without an Amp Modeler

Serial, parallel and wet/dry paths are supported, along with a movable effects loop, two noise suppressors, volume control and global EQ. MIDI, USB-C and expression control round out the connections. At $329.99, it fills the space between a single-category Boss pedal and a larger processor built around amp models.