Erica Synths Bullfrog XL Analog Desktop Synthesizer - USA Plug

Some synthesizers are designed to hide their complexity—Bullfrog XL puts it front and center, albeit with a creative twist. Created by Erica Synths in collaboration with renowned electronic DJ/musician Richie Hawtin, Bullfrog XL is a fully analog desktop synthesizer that combines a complete subtractive synthesis voice with modular-style utilities and visual learning tools. Scaled up to three times the size of the original Bullfrog, the XL format improves ergonomics, visibility and patching clarity while preserving a pure analog signal path. With built-in speakers, a dual-channel oscilloscope and an expandable voice-card system, Bullfrog XL serves as both a serious creative instrument and a hands-on platform for understanding how sound is shaped from voltage to waveform.

Classic Subtractive Synthesis With Modular Utility Depth

Bullfrog XL leverages a traditional analog synthesis architecture built around a precision VCO, resonant low-pass VCF and VCA, all designed to clearly demonstrate each stage of sound creation. The oscillator offers continuous waveform shaping from sine to shark-fin, pulse output with PWM and stable pitch tracking across a wide range. Supporting modules—including dual looping ASR envelope generators, a sample-and-hold circuit with clock, slew processor, noise generator and clock divider—bring modular-style depth without requiring an external Eurorack system. These elements allow Bullfrog XL to move easily from clean melodic tones to evolving textures, percussive sounds and controlled randomness.

Visual Sound Design With Integrated Oscilloscope

What truly defines Bullfrog XL is its built-in dual-channel oscilloscope, which turns abstract synthesis concepts into visible, real-time feedback. Users can monitor waveforms, envelopes, modulation signals and control voltages directly on the instrument, adjusting time and amplitude scaling, trigger modes and math functions to explore signal relationships. The oscilloscope makes it easy to understand how modulation affects pitch, filter movement and amplitude, reinforcing the connection between patching choices and sonic results. This visual approach transforms Bullfrog XL into a powerful educational tool while remaining fully usable as a performance instrument.

Expandable Voice Cards and Creative Integration

Bullfrog XL is designed to grow with its user through a dedicated voice card expansion slot, which allows additional synthesis, sequencing, filtering or sampling capabilities to be introduced into the system. Included and optional voice cards integrate seamlessly into the analog signal flow, expanding Bullfrog XL beyond its core subtractive engine. Large-format patch points, MIDI connectivity, built-in speakers and a durable desktop enclosure make it equally suited for studios, classrooms and experimental performance setups. For producers, educators and sound explorers seeking an analog synthesizer that rewards curiosity and hands-on learning, Erica Synths' Bullfrog XL offers a uniquely transparent and musical path into synthesis.