Playing around with the Minisonic II Analogue Synthesizer

[janxenjanxen]

toys toys toys ;-)

[fritagogo1]

Ooops Electronic Wave Research with Mini Sonic ! 1973 !  Ok !

[thickinthead]

Thanks for putting this up. I also built one of these back in '74. The oscillators were temperature compensated by using stuck-together emitter coupled trannies (didn't the original use a crystal oven?), but mine still drifted wildly. The close tolerance resistor chain for the keyboard just wasn't close enough to make an even-tempered scale, and the ring modulator didn't modulate. Still, it taught me a lot about basic synths and was fun (bloody expensive fun!) to build.

[ricardlupus]

I started out building one of these, the original version from Practical Electronics magazine. Great starting point if you were on a tight budget, as I was as a young teenager. The original oscillators were completely uncompensated, so consequently drifted wildly with temperature. The Minisonic II was better, but I still had problems getting them to track properly. And I never got the envelope generators to work at all. Filter was nice, had a hint of organic Moog quality, being a ladder design.

[DarkGlassly]

Nice to see it here - I made one myself at the time. Still have it buried away somewhere. It suffered from a few design flaws, but good to play around with and modify.

[cogshiftingman]

@DarkGlassly Thanks for the comment. If you decide to sell your original, please let me know - I'd like to have one as a comparison.

[DarkGlassly]

@cogshiftingman Think I'll be hanging onto it for a little longer. Your video has inspired me to dig it out and have a play, so I may do a demo video myself when I have time. I did make improvements to it, adding an ADSR generator, new pitch detector and switchable waveforms, but of course it still has some of the original problems such as drifting VCOs and slight pitch change induced by the ultrasonic key switching technique it used.

[cogshiftingman]

@DarkGlassly I look forward to the demo! I spent ages setting up the VCOs on mine. I was hampered by having to use a bonded transistor pair for one of them rather than the original dual transistor. The key switch/hold using HF is neat - I didn't have any problem with that part.

[DarkGlassly]

@cogshiftingman The "pitch droop" was a variable problem, occurring when the key was released, I was never able to resolve it. Just seen your web site page about the Minisonic - excellent! I replaced most of the 741 ICs with LF351, which improved the sound quality with its much higher slew rate and lower noise. I did have the 128-note sequencer for the synth up until a few years ago, which I threw away.

[timjmoran]

wow.. what a cool looking synth!! Is this a contemporary synth? Or vintage?

Made in the US? Looks kinda vintage to me....

[cogshiftingman]

@timjmoran Thanks - I made it myself: electronics are from a 1973 design. Cabinet design my own.

[KINZOisHERE]

you could do amazing fat nasty dubstep with that machine :)

[AdrienChaos]

Hey man all I am saying is that i don't understand the point of something that just makes one noise that can be messed with.. I don't think its a synthesizer its just a humming box with a keyboard attached to it..

[cogshiftingman]

@AdrienChaos The Minisonic II contains two VCOs, a VCF, a Noise Generator, two Envelope Shapers, a Ring Modulator, phase locking and dual pan/fade amplifiers. By all definitions, it is a functional analogue sound synthesizer. If you want to read more about it, Google "Minisonic2 Analogue Sound Synthesizer".

[AdrienChaos]

@cogshiftingman That's great but still, to the normal person who doesn;t understand synthesizers, well, even to me I still don't get the point///

[cogshiftingman]

@AdrienChaos There is no point, really - it's just for fun. In the video I was just concentrating on showing some of the VCF and Ring Modulator effects, rather than playing anything tuneful :-) Perhaps that's why it sounds pointless to you?

[AdrienChaos]

@cogshiftingman ahhh... Ok I see now so its demonstrating the effects,,, Can the synth play anything tuneful?

[hellsmaw84]

@AdrienChaos working with a synth or a DIY synth is that of the imagination. you make the beat and you make the melody. the best route is to make/buy multi channel gate sequencers. the Doepfer 3/16 (3 16 individual gate sequencers in one package), MFOS 16 step gate sequencer (POSSIBLE OBSOLETE/NO SELL BOARDS!), and many other DIY/buy sequencers are nice. but above all, learn electronics and learn about oscillators! that or just go out and buy an expensive keyboard with all the features in it ;)

[thephaseshifter]

very organic sound

[bolijack]

My kids are making far better noises, and no machine :-((

[cogshiftingman]

@bolijack Great - you must be relieved.

[NamesROverated]

@bolijack You should probably get that checked

[anoteoftruth]

Oh man would I ever love to have one of these!!!! Great vid!

[dirtbiker888]

cool. did you build that? I still have a half built original minisonic from the 1970's which I'm trying to finally test and complete in 2010!

[cogshiftingman]

Yes, I did. I have a web page describing the build. I'm also in touch with the guy who designed the Minisonic, G.D.Shaw. I'd be interested to hear more about your Minisonic.

[dirtbiker888]

Yes, I have the original PCBs, etc. and had given up on building it as I didn't have the proper test equipment, etc. (After all, I was not even a teenager then!) Bit off more than I can chew, but now that I've resurrected it, I've been testing the modules separately and seem to be making some headway. Uncovered a ton of misconnections, etc. It has all the original hard to find parts such as the noise diode, Z1J, etc. I actually bumped into your website as well.

[retrocareermelted]

I love turning the bass up loud on synths

[RuXTaR]

I have yet to find a video of someone playing it! is that all it does? noise?!

[cogshiftingman]

Noises is all it makes when I play it. No doubt a skilled pianist like yourself could play a tune on it.

The only videos you will find of this are here: it is a unique instrument - nobody else has one. So if you are looking for a performance of the Toccata and Fugue in D Minor, you are SOL :-)

[Sykopuppet]

where do you buy the synthesizers at

?

[rondroyd]

yo i can get onne whit problem ya have any info on the net some where i can check

looks nicey

[DreHectik]

very nice sound, from a very nice machine.  controled by a human.

[avinunca]

I built the original one years ago. Great project. VCO's used to drift badly though but made some good sounds.

[doom705]

great sunth i fucking love it. I've got a sequencal pro one thats similar