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Roland Alpha Juno 1




Roland Alpha Juno 1


audio demo trend price : 200€
manual demo demo video comments


Roland Alpha Juno 1 (1985)


The last of the Classical Juno series, mostly aimed at low-cost target.

Some interesting hybrid analog & digital characteristics with Midi interface and memory.


alpha juno waveforms

juno sawtooth

info KEYBOARD 49 keys with no velocity nor aftertouch.
The main panel has 38 membrane buttons + single jog wheel Alpha Dial for data entries: just a few knob for edit... definitively NOT an easy job! however there are 4 shortcuts functions TONE MODIFY for direct access to some parameters like EG attack, brilliance VCF-cutoff, modulation depth and rate.
On the left side board has a Joystick that works as pitch bender and modulation, just nearby some functions buttons : octave transpose, portamento and chord mode memory (outputs also MIDI notes).
Rear panel terminal connectors: Midi and tape interface, stereo output, headphones jack and 3 pedals inputs for Volume pedal for expression (volume, aftertouch and dynamics), 2 footswitches for HOLD and other assignable functions (patchUP, portamento and chord memory).

acPower supply is internal

edit VOICE based on a main CPU Intel 8032AH manages 6 voices.
Each voice has a single DCO with variable octave range from 4' to 32' based on custom Roland IC MB87123P-G which is able to layer and mix various waveforms. The result is a bit quite weird raw sound with some digital background, but not necessary a bad point.


edit Let's deep the waveforms sections:
- Pulse: 3 different shapes, the last one has variable width.
- Saw: 5 different shapes with variable width
- Sub-oscillator: pulse or saw waveforms with 1 or 2 octave lower range
- White noise: just mix volume paramter.

adsr LFO a single modulator assignable to VCA and VCF- each destination has individual Depth but they share same rate frequency. Just one parameter for modulation engage delay time.


adsr ENVELOPE there is a single-shared EG for amplitude and filter with possbile polarity inversion.
EG counts 4 stages segments + 3 time levels AABBDSR with key follow (keytracking) function for amplitude compensation over octaves.

filter FILTER is a multimode analog resonant filter with CPU quantised values based on 6* IR3R05 same found Jx10 jx8 or Mks70.
The Alpha filter structure is a 4 poles lowpass + high-pass but only 4 fixed rates values.
korg ex800

edit EDIT main panel is poor! but there the Midi Exclusive system implementation is rich, in fact
it can be edited by computer software or using the optional programmer model Pg-300, but this arare piece of extra could reach even higher price than the synth itself.

section features an analog stereo chorus based on traditional MN3101 - MN3009 (like Juno 60 or Jx3p) with adjustable rate in a old Roland fashioned way: the chorused sound floats around your speakers using stereo outputs.

midi MIDI basic Control Changes parameters,

memory MEMORY holds up to 64 ROM sounds + 64 RAM ones.
No way to expand memory in any internal or external media.
All internal settings are memory backup on a lithium CR-2032 soldered to the mainboard.
memory Updated alpha Juno II have cartridge facility called M64-C (the same found on tr-707, jx10, mks-80).
Roland Ju1 mainboard
soldered lithium CR-2032 battery


mks50 pg300

- Alpha Juno 2 - is bigger with 5 octave keyboard Velocity and aftertouch sensitive keyboard.
- HS-10 - an alpha juno1 with different case.
- MKS-50 1 rack unit with some enhancements like Detuning, Portamento and a double RAM memory.
- PG-300 programmer compatible with all the JUNO series.

alesis d4 audio demo


* along with drum machine Roland Tr606


Roland Alpha Juno 1 Roland Alpha Juno Techno Demo Track Alpha Juno 1 Hoover
Roland Alpha Juno 1 Roland Alpha Juno Techno Demo Track Alpha Juno 1 Hoover

original scan








roland epom alpha juno motherboard alpha juno motherboard


- cute, easy to carry
- still a Juno
- strange DCOs



- editing
- EG / LFO
- no arpeggiator

stange machine!


"a near classic ! Still a little good analog with good basses .The oscillators have something weird and digital. Try it before buying, it can be an original cheap source of analog sounds. "

alpha juno logo



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all snapshots, sounds, texts copyright Polynominal.com / Eric Pochesci

roland alpha juno1 4.5 out of 5 based on 23 ratings. price €200