Roland Alpha-Juno 1 (1985)

Roland Alpha-Juno 1

 
UNDER THE HOOD
Inside Roland AlphaJuno

Inside Roland AlphaJuno

Inside Roland AlphaJuno

Inside Roland AlphaJuno

Inside Roland AlphaJuno

Inside Roland AlphaJuno

Inside Roland AlphaJuno

Inside Roland AlphaJuno

 
MAIN DSP, ELECTRONICS, CHIPS PDF DOCUMENTS
IR3R05
MB87123P-G
MN3009
MN3101
M5241
NEC C4570C
Intel 8032AH (1)
Intel 8032AH (2)
 
IMPRESSION

Aaah the so so famous Roland « Junos » . Thousands and thousands of testimonials had been written on this long series of synthesizers, including the Juno6, Juno60 and the most famous: Juno-106. Around 1985, Roland decided to create two new Juno models : the Alpha-juno1 and 2. Unfortunatly the look of those synthesizers are very « cheap » and almost like plastic toys compared to the Juno6/60/106 line … For me, this all explain the bad reputation given to this synthesizer.

This « supposed » bad sound quality is a vast lie, and even if you have to loose an arm and a leg by reading this, I will go straight to the point, telling you that the Alpha-Juno1 and 2 are far better engineered than the Juno6/60/106 serie. Let’s forget the cheap plastic « look » and the lack of controls on the front panel of this synth. In 1985, almost all synthesizer manufacturers took the fold to offer a panel with only a few buttons and an LCD screen as a programming interface (officialy to reduce the cost). Yamaha and its series « DX » just started this new fashion years ago.

But I’d like to come back to the essential: the sound engine of the synthesizer. Whereas the Juno6/60/106 offers only one oscillator per note played with only two waveforms available (sawtooth,  adjustable rectangle length (either fixed or variable by using the LFO)… with Alpha-Juno, we have 14 waveforms offering different variations of sawtooth and square (impacting the harmonics). On this synth, there is also only one single oscillator to play a note, but this oscillator can generate up to three waveforms simultaneously. And the combination of three families of waveforms among the 14 available makes it possible to create an infinitely more promising and vast harmonic content than the very basic oscillators from the Juno6/60/106 series.



Then we have a filter (24dB / oct) which does not have to be ashamed of the comparison with the illustrious jupiter. The chorus effect is also present and, like all the Juno series, it generates lots of noise from its use but nevertheless this noise is definitely less present. As a bonus, the chorus has finally few parameters available. The envelope is more elaborate. Instead of the traditional ADSR, we now have 8 segments envelope. This makes it possible to vary the sound in a more complex way than a simple upward or downward slope. The polyphony is still six notes.
The oscillator circuit is an MB87123P-G. The filter and the management of the VCA is a Roland home made circuit, the IR3R05 (see photos of the internal view of the synth). This chip can be found in the MKS80 (Jupiter-8 in a rack). The VCA chip is a M5241. The chorus circuit is a MN3009.
I had a Juno-106 which I never really liked too thin and too smooth for my taste, but however I still own the first Juno, the Juno-6 … which offers a sound one Not much less smooth than the 106, but which nevertheless is far less rich than that which can emerge from the Alpha-Juno.

A summary table of the main circuits of the Alpha-Juno :

  • DCO : 6x IC MB87123P-G
  • VCF/VCA : 6x IR3R05
  • AMP : 1x M5241 / 6x C4570C
  • CHORUS : 2x MN3009 + 2x MN3101
  • CPU : 1x Intel 8032AH

For years, I’ve tried to read constructive arguments that would make it possible to understand how the Alpha-Juno are assumed to be « inferior » to the Juno6/60/106 … But I’ve never read anything but gaps that have no arguments. To these people I would propose to download this small text file that includes all the parameters to create a sound that I use very often. It’s the most bold, thickest, most impressive analog sound I’ve ever heard on a synth of this kind. Then I invite you to try to program the same sound on your Juno6/60/106 and send me your results.
Click this link to download the"FAT SYNTH1" sound settings

The Alpha-Juno is for me one of the best analog synthesizer I’ve ever used. Yes there is only one single oscillator but combines 3 waveforms simultaneously, which makes it possible to create sounds really complex and powerful! The sound is extremely warm, thanks also to an excellent filter. Do not rely on its plastic « toy » look « !
What comes out of this fabulous machine is a HUGE sound !