Stereo modulation pedal 
with classic Chorus, Flanger, and Tremolo effects, tap tempo, and selectable true or buffered bypass operation via mobile app

With Astra Modulation Machine, Universal Audio's engineers traveled down a rabbit hole of analog modulation effects, emerging with the most authentic sounding bucket-brigade chorus/vibrato, studio flanger/doubler, and tube-driven tremolo ever put into a stompbox. Built upon powerful UAFX dual-engine processing for unmatched levels of quirky analog realism, Astra delivers richly addictive vintage modulation sounds built to inspire for decades to come. Astra gives users the most complete circuit emulation of the legendary gray bucket-brigade chorus stompbox. Harnessing a perfectly-emulated circuit — including its preamp section for authentically rich, saturated sounds — users can paint their tones with the thick, luxuriant chorus and wavy vibrato of a famed ‘70s modulation effect. Classic rackmount studio flanger/doubler is famous for stunning whoosh effects, organic thickening, and a parade of wild sounds that go beyond typical flanger boxes. Astra's Flanger/Dblr effect is the only end-to-end circuit emulation of this ultra-rare unit, capturing all of its original qualities and putting dense, complex flanging/doubling right at your feet. Trem 65 is a faithful emulation of the optical tube-driven tremolo of '60s American amplifiers. From shimmering ripples to choppy mayhem, UA captured every detail, down to the complex interactions between the light source photoresistor and 12AT7 driver tube. Plus, users can explore further and create their own trem textures with variable sine and square wave settings. Astra's UAFX engine powers separate stereo instances of each modulation effect, thanks to its unique dual-engine processing. It's like having two bucket-brigade hardware units running simultaneously, giving users a full stereo spread of complex, jaw-dropping textures. With modern, high-powered features like studiograde conversion, dual processing engines, Live/Preset modes, plus selectable true or buffered bypass and tap tempo footswitch mode via the UAFX Control app.

Chorus Brigade: Iconic Japanese Modulation

Upon its release in 1976, this legendary gray bucket-brigade stompbox changed the sound of music with its thick, luxuriant chorus and wavy vibrato. Astra's Brigade Chorus mode gives you the most complete circuit emulation of this landmark unit — including its preamp section for authentically thick, saturated sounds — letting you paint with subtle ripples of analog texture and tone, adding chewiness, shimmer, and motion to everything you play.

Flanger/Doubler: A Rackmount Studio Classic

Packed with late-'70s bucket-brigade tech, this classic rackmount studio flanger/doubler is famous for stunning whoosh effects, organic thickening, and a parade of wild sounds that go way beyond typical flanger boxes. Astra's Flanger/Dblr effect is the only end‑to‑end circuit emulation of this ultra‑rare unit, capturing its original features to a "T" and putting impossibly dense, complex flanging/doubling right at your feet.

Trem 65: Authentic Tube Amp "Shake"

Few things compare to the optical tube-driven tremolo of '60s American amplifiers. Deep, undulating, and the very essence of vibe, Trem 65 is a faithful emulation of this classic circuit. From shimmering ripples to choppy mayhem, every dynamic detail is captured in UA style, down to the complex interactions between the light source photoresistor and 12AT7 driver tube. Plus, you can explore further and create your own trem textures with variable sine and square wave settings.

Dual Stereo Modulation Engines for Endless Creativity

Astra's UAFX engine powers separate stereo instances of each modulation effect, thanks to its unique dual‑engine processing. It's like having two bucket-brigade hardware units running simultaneously — or even dual tremolo circuits — giving you a full stereo spread of complex, jaw‑dropping textures.

A State-of-the-Art Stompbox

With modern, high‑powered features like studio‑grade conversion, dual‑processing engines, additional downloadable effects at registration, Live/Preset modes, true/buffered bypass,* and silent switching, Astra Modulation Machine has your colors — now go forth, and paint your masterpiece.

• Flagship, no-compromise stompbox offering the most authentic bucket-brigade and tube-driven tremolo effects ever captured in an effects pedal
• End-to-end emulation of iconic Japanese chorus/vibrato pedal
• Complete circuit capture of legendary '70s rackmount studio flanger/doubler
• Stem-to-stern model of tube-driven optical tremolo from classic '60s American amps
• Store and recall your favorite preset, silent switching, and true/buffered bypass
• Free Phaser X90 and Dharma Trem '61 effects, downloadable at registration

Technical Specifications

• Dimensions: 2.56" H x 3.62" W x 5.55" D
• Weight: 1.24 lbs
• Inputs: 2 x 1/4"
• Outputs: 2 x 1/4"
• Power Source: 9V DC 400mA power supply (sold separately)
• USB: 1 x USB-C (Firmware updates)
• Effects: Chorus, Flanger, Tremolo
• Processing Type: Digital