Built for the stage,
not the studio

Arcsin Engineering makes mobile signal processing tools for musicians who perform live. Our hardware is compact. Our software is fast. Everything we build is designed to work under pressure — bad lighting, loud monitors, no time to debug.

Our first product, the LIMIT-1, is a mobile hardware multieffects unit with an iOS companion app. It combines JUCE-powered C++ audio processing with a SwiftUI interface, keeping latency below 10ms while giving performers full control from physical knobs and a touch screen.

We believe the best gear gets out of your way. No menus, no modes — just the sound you need when you need it.

Stage First
Every design decision is tested against one question: does this work at a gig? Gloves, low light, loud stage.
Zero Latency
Sub-10ms round-trip target. We don't compromise on audio responsiveness — it's the core of everything.
Hardware + Software
Physical knobs, digital intelligence. The best interface is the one you don't have to look at.
Open Build
Development happens in the open on GitHub. We document the process, not just the product.

Hybrid architecture

Each layer speaks its native language. Swift owns the UI. C++ owns the DSP. Objective-C++ translates between them — no compromises in either direction.

UI
SwiftUI
IR loader · Plugin chain · Knob carousel
Swift
Bridge
Objective-C++ (.mm)
AudioEngineWrapper · ParameterBridge · MIDIBridge
ObjC++
DSP
C++ / JUCE
AudioProcessorGraph · ConvolutionEngine · AUv3 Host
C++17

Stack

JUCE
C++ audio engine, IR convolution, AUv3 plugin hosting, cross-platform audio I/O
C++17
SwiftUI
All UI — knob carousel, IR loader, plugin chain manager, swipe navigation
Swift 5.9
MIDIKit
Core MIDI abstraction, hardware CC parsing, bidirectional parameter sync
Swift Package
SwiftData
Preset persistence, IR file references, plugin chain storage, iCloud sync
iOS 17+