The Roland Alpha Juno series, introduced in 1985, includes two analog polyphonic synthesizers: Alpha Juno 1 and 2.

Produced until 1987, they were priced at US$895/ UK£575 for the Alpha JunoJ-1 and US$1,295/ UK£799 for the Alpha Juno-2. They share the same sound engine but differ in performance features. Unlike their predecessor, the Juno-106, they use soft touch buttons and a single dial for programming instead of many potentiometers. That renders quite uncomfortable programming the synth. The optional Roland PG-300 programmer made every MIDI parameter editable with a dedicated slider or switch.

Technical specifications include 6-voice polyphony, monotimbral operation, and 1 DCO per voice with pulse, saw, square, and noise waveforms, plus a sub-oscillator. They feature a triangle LFO, analog 24dB/oct resonant low-pass filter, and multistage envelope generator with Level/ Time parameters (L1, L2, L3 available for each of T1/T2/T3/T4 or ADSR). Both models have 128 patch storage (64 user, 64 preset) and a chorus effect.

The Alpha Junos use an "Alpha dial" for editing, with some parameters having dedicated selector buttons. They offer expanded oscillator choices compared to the Juno-106, including multiple pulse and sawtooth waves, and a sub-oscillator. The synthesizers feature a multi-stage envelope design with eight parameters and a Yamaha DX7-style envelope chart on the control panel.

The Alpha Junos include a programmable chorus effect, improving upon the Juno-106's fixed dual-rate chorus. The Alpha Juno-2 offers aftertouch and velocity expression (5-octave, 61 keys), absent in the Alpha Juno-1 (4-octave, 49 keys). Both support MIDI for external control.

Roland released the HS-10 as the equivalent of the Alpha Juno-1, and the HS-80 as the home market version of the Juno-2.

The Alpha Juno-1 has a plastic body sitting on a metal frame, while the Juno-2 has metal body (except plastic sides) and is much heavier because of semi-weighted keys.

Upon the release, the Alpha Juno was not achived that much of popularity, but years later, a factory preset, dubbed the "hoover sound", became popular in jungle and rave music. After 30 years, the Alpha Juno slowly but surely attracts more and more vintage analog gear enthusiasts. This happens not only because it sounds so good, but also due to its outstanding reliability - you would have no major issues except failing aftertouch and, sometimes, internal battery to replace or keybed contacts to clean.