Analog-style polyphonic synthesizer for iPad
LH Rubbing
LH Rubbing is a polyphonic iPad synthesizer designed around a distinctly analog-style sound. Its warm, rounded, responsive character gives notes a sense of movement and physical presence, while Keyboard Rubbing and touch-based control make vibrato part of the act of playing.
Analog-Style Sound
LH Rubbing focuses on the warmth, movement, and immediacy associated with analog synthesizers. The sound can feel rounded, vivid, and slightly organic, giving sustained notes and evolving tones a strong sense of character.
App Store Editorial Recognition
First released in 2013, LH Rubbing was Liu Hao’s first iOS software synthesizer and received App Store editorial recommendation after its release.
Keyboard Rubbing and Touch Performance
Keyboard Rubbing is the instrument’s distinctive performance feature. Rubbing across the touch keyboard introduces vibrato, while the same gesture controls vibrato rate and depth. The touch interface makes expression part of the movement of the player’s hand rather than a separate adjustment.
Oscillators and Multimode Filter
LH Rubbing provides three waveform oscillators. Each oscillator can generate triangle, square, or sawtooth waves, and a separate noise oscillator adds another source for richer or more textured sounds.
The embedded multimode filter offers low-pass, high-pass, and band-pass modes. Filter cutoff frequency and resonance can be shaped through modulation and the ADSR envelope generator.
Dual-LFO and ADSR Modulation
Two LFOs provide layered modulation. LFO routing can affect oscillator pitch, pulse width, filter cutoff, filter resonance, and oscillator output mixing. The second LFO can also modify the frequency and amplitude of the first LFO, creating more complex movement.
The ADSR envelope generator can control pitch, filter cutoff frequency, and filter resonance, extending the envelope beyond conventional amplitude shaping.
Core Features
Analog-Style Polyphonic Sound
Combines oscillators, noise, filtering, modulation, and envelopes for a warm analog-style character.
Three Waveform Oscillators
Each oscillator can generate triangle, square, or sawtooth waves.
Noise Oscillator
Adds a separate noise source for textured and more complex timbres.
Dual LFO Modulation
Uses two LFOs for oscillator, pulse-width, filter, resonance, and output-mix modulation.
LFO-to-LFO Modulation
Lets the second LFO modify the frequency and amplitude of the first LFO.
Three-Mode Filter
Provides low-pass, high-pass, and band-pass filtering.
Extended ADSR Routing
Applies the ADSR envelope to pitch, filter cutoff frequency, and filter resonance.
Keyboard Rubbing
Turns rubbing gestures on the touch keyboard into vibrato with controllable rate and depth.
Touch-Based Performance
Uses direct touch interaction for expressive control while playing.
LH Rubbing FAQ
What is LH Rubbing?
LH Rubbing is a polyphonic synthesizer for iPad with an analog-style sound and a touch-based Keyboard Rubbing performance interface.
Why is it called LH Rubbing?
The name refers to Keyboard Rubbing, a performance interaction in which rubbing across the touch keyboard introduces vibrato and controls its rate and depth.
Which oscillator waveforms are available?
Each of the three waveform oscillators can generate triangle, square, or sawtooth waves, and the synthesizer also includes a separate noise oscillator.
What can the LFOs modulate?
The LFOs can modulate oscillator pitch, pulse width, filter cutoff frequency, filter resonance, and oscillator output mixing. The second LFO can also change the frequency and amplitude of the first LFO.
Which filter modes are included?
LH Rubbing includes low-pass, high-pass, and band-pass filter modes.
Did LH Rubbing receive App Store editorial recognition?
Yes. LH Rubbing received App Store editorial recommendation after its release.