FM · unison · parallel filter shaping
LH Resistor
LH Resistor is a flexible iOS synthesizer designed for detailed sound shaping. A selectable waveform forms the basis of the FM voice, which can expand from one voice to nine unison voices. Parallel filter outputs and layered modulation make it possible to build focused tones, broad leads, dense basses, and evolving textures.
FM Sound Design
A selectable source waveform forms the basis of the FM voice. Modulation ratio, fine ratio, and FM index can be adjusted independently, making it possible to move from clear and stable tones to increasingly complex harmonic textures.
FM index can be shaped by both an ADSR envelope and an LFO. A blend control balances these two sources, while a sub-LFO can vary the LFO rate for slower, more complex movement.
One-to-Nine-Voice Unison
The voice can be expanded from one to nine unison voices. Detune, phase offset, and phase variation control how tightly the voices move together, ranging from a focused single voice to a wider and more animated unison sound.
Parallel Low-, Band-, and High-Pass Shaping
Low-pass, band-pass, and high-pass outputs are available simultaneously. Each branch has its own level and ADSR envelope before the three outputs are mixed together, allowing separate parts of the spectrum to move and develop over time.
Layered LFO Modulation
A second LFO system can modulate pitch, FM modulation ratio, fine modulation ratio, and the output levels of the low-pass, band-pass, and high-pass branches. Its rate can also be varied by a sub-LFO, and modulation directions can be inverted to create related movements in the same or opposite directions.
Real-Time Performance Controls
Global octave and fine tuning, pitch bend, filter cutoff and resonance, individual filter-branch levels, modulation depth, and output level can all be adjusted in real time.
Effects and Presets
Chorus, stereo Delay, and Reverb add width, repetition, and space. Chorus provides several behaviors, Delay offers time and level control with a subtle stereo difference, and Reverb provides multiple room-size and damping combinations.
Preset saving and loading make complete sound configurations easy to recall, compare, and continue developing.
Core Features
Selectable-Waveform FM Voice
Uses a selectable waveform as the starting point for FM sound design.
FM Index Envelope and LFO
Combines an ADSR envelope, an LFO, and sub-LFO rate variation for FM index control.
One to Nine Unison Voices
Expands a single voice into as many as nine detuned voices.
Phase Offset and Variation
Controls the phase relationship and variation across the unison voices.
Parallel Filter Outputs
Provides simultaneous low-pass, band-pass, and high-pass outputs.
Independent Filter Envelopes
Shapes each filter output with its own ADSR and level.
Flexible LFO Routing
Routes modulation to pitch, FM ratios, and the three filter-output levels.
Sub-LFO Movement
Uses sub-LFOs to vary the rates of the main LFO systems.
Chorus, Stereo Delay, and Reverb
Adds width, repetition, depth, and spatial character.
Preset Management
Saves and loads complete sounds for recall and continued sound design.
LH Resistor FAQ
What is LH Resistor?
LH Resistor is an iOS synthesizer with selectable waveforms, FM sound design, one-to-nine-voice unison, parallel filter shaping, layered LFO modulation, built-in effects, and preset management.
How can the FM sound be shaped?
Modulation ratio, fine ratio, and FM index can be adjusted independently. FM index can also be controlled by a blend of an ADSR envelope and an LFO.
How does the filter section work?
Low-pass, band-pass, and high-pass outputs are available simultaneously. Each output has its own ADSR envelope and level before the three branches are mixed.
What can the second LFO modulate?
The second LFO can modulate pitch, FM modulation ratio, fine modulation ratio, and the output levels of the low-pass, band-pass, and high-pass branches.
How does unison work?
LH Resistor supports one to nine voices with detune, phase offset, and phase variation.
Which effects are included?
LH Resistor includes Chorus, stereo Delay, and Reverb.
Can presets be saved and loaded?
Yes. Complete sound configurations can be saved, loaded, compared, and developed further.
Does the current version support Audiobus, AUv3, or external audio routing?
The current version is focused on standalone use and does not include Audiobus, AUv3, or other external audio-routing integration.