The Flow Vintage Tremolo brings three distinct flavours of tube-driven modulation to your pedalboard, evolved from the acclaimed Astra Modulation Machine into a compact, sophisticated package. This pedal captures the chewy throb of early '60s American “brown” amps while adding a syrupy blend of volume fluctuation and phase shifting that goes well beyond the original circuit capabilities, making it perfect for vintage soul, surf, and even Uni-Vibe textures.
At its heart lies an exhaustive end-to-end emulation of a classic 1965 American tube amp's optical tremolo circuit, recreating the pulsating shimmer of the most famous “vibrato” ever created. UA's custom virtual optical photocell technology delivers the rippling beauty of square waveforms, opening up rhythmic tremolo effects that enhance everything from modern pop and R&B to blues and indie rock.
The warm, complex sounds of a tube preamp from early and mid-'60s American combos ensure your tremolo effects are more present, three-dimensional, and musical. Built for reliable performance, the Flow Vintage Tremolo features switchable true/trails bypass, tap tempo, and “make up gain” Volume control to keep your tremolo effects heard loud and proud for years to come.
- Authentic emulations of three tube-driven tremolo effects, captured in a compact stompbox
- Perfectly captured tube preamp for fat, three-dimensional tremolo tones
- Three tremolo modes: Dharma (harmonic tremolo), 65 (round, sine wave), and Square (choppier, square wave)
- Onboard tap tempo for syncing trem effects
- Volume control and true/buffered bypass
- Timeless UA design and craftsmanship, built for decades of dependable performance
- Power requirements: Isolated 9VDC, centre-negative, 250mA minimum (sold separately)
- Inputs: 1 x 1/4” TS unbalanced
- Outputs: 1 x 1/4” TS unbalanced
- USB Type-C for updates via computer
- Height: 5.81 cm, 2.29 inches
- Width: 6.55 cm, 2.58 inches
- Depth: 12.07 cm, 4.75 inches
- Weight: 0.659 lbs (0.299 kg)



