Arcsin Engineering — Hardware & Software

Our
Products

Purpose-built hardware and software for performing musicians. Every product designed around one constraint: it has to work on stage.

In Development
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LIMIT-1
Arcsin Engineering
Featured product
LIMIT-1
Mobile Multieffects Unit

A hardware multieffects processor paired with an iOS companion app. Load impulse responses, chain AUv3 plugins, and control every parameter from 8 physical knobs — built for the stage, not the studio.

The iOS app bridges native SwiftUI with a C++ audio engine via Objective-C++, keeping UI and DSP in their natural environments with sub-10ms round-trip latency.

Latency
<10ms
Controls
8 Knobs
Platform
iOS / macOS
Engine
JUCE / C++
View dev log → GitHub
Technical specs

LIMIT-1 specifications

Audio Engine
JUCE / C++17 — AudioProcessorGraph with ConvolutionEngine
UI Framework
SwiftUI — knob carousel, IR loader, plugin chain manager
Bridge Layer
Objective-C++ (.mm) — AudioEngineWrapper, ParameterBridge, MIDIBridge
Plugin Format
AUv3 — XPC process isolation, live chain reordering
IR Loading
.wav impulse responses, background thread init, gain normalisation
MIDI
Core MIDI via MIDIKit — bidirectional CC sync, feedback loop prevention
Persistence
SwiftData — presets, IR references, plugin chains, iCloud sync
Platforms
iOS → macOS (Catalyst) → Windows (JUCE backend)
Target latency
<10ms round-trip audio
Knob targets
88pt minimum — designed for gloves and low-light stage use
Status
In active development — milestone 02 / 09 complete
On the roadmap

What's next

Concept
LIMIT-1 Desktop
macOS / Windows

Full macOS app via Catalyst and a native Windows build on the same JUCE audio engine. The C++ DSP layer is already platform-agnostic — only the UI shell adapts per target.

Research
IR Library
Cabinet Impulse Responses

A curated collection of cabinet impulse responses optimised for live use — low-latency, normalised, and tagged by speaker type, mic position, and genre.

Concept
LIMIT-2
Next Generation

8-knob hardware revision with USB-C audio I/O, expanded parameter mapping, and a larger form factor designed for studio-to-stage portability.