Praise for Shruthi-1 and its developer

I have just finished building my Shruthi-1 kit, after buying it way back in February this year.

It has brought back lots of memories for me. I used to enjoy building circuits from schematics I found in magazines as a teenager, from my pocket money. Every once in a while something would not work as it should after days/hours of work and I did not have a clue where to start diagnosing the faults: Still the transmitters, flashing LED’s, more than made up for it.

Fast forward to 2011, when I finished soldering all the pieces of my Shruthi-1, it did not seem to produce any sounds. This time, however, thanks to Mutable Instruments, it was explained very clearly how to trace problems. 3 a.m. Saturday morning, I found myself vandalising an audio cable lying around to trace the signal on my SM-4 board. A-ha! It does produce tones… At all points, except point 8. Quick look at the schematics, and using the cheap old multimeter, it took me less than 10 minutes to narrow it down to 1 specific connection and resoldering this solve the problem!

I could not get the filter to self-oscillate. Resonance seemed to work but for some reason not as high to make a sine wave. Who cares?! I put it in the box connected the leads, to try it out…

The sound on this thing, however, is still amazing! I have loads of digital and analog equipment in my set up but none of them have the quality of presets that this little thing does. I was expecting to like the sound but I was taken aback by how MUCH I liked it.

The next day, I decided to go through the sequencer patterns. Blimey! The first 10 or so, particularly! They are exactly the patterns that I try to program on every synth…

I just want to say, THANK YOU to Olivier for developing this little gem and for the clear instructions for people like me who may or may not know what they are doing.

I need to go and play it a little more now!


well said.



+1 here too. I love my Shruthi and building it has rekindled my interest in electronics - I’m ordering some parts for a homebrew opto-compressor right now!

Yes indeed,
I had a blast putting it together,
10x that much fun using it!
Amazing the sonic capabilities of this synth, and features it has!


I just signed up for membership and ordered a Shruti-Kit incl. housing.

Browsing through the forum and the website, I wanted to thank the creator of mutable-instruments for his work and effort.

For years I wanted to develop something like the Shruti/Ambika on my own, but every time I started, things happened (girlfriend, now Wife…Child…buying a house etc.) and lead me away from it… so I spent most of my time repairing old analogue synths and collecting them.
I am 43 and have a degree (Dipl.-Ing) in electronic engineering…for over 25 years I am developing embedded control devices, doing schematics and layouts with EAGLE, programming in Assembler (Z80,8051) and C (Renesas R8,M16,M32 and ARM).

Monsieur Gillet, as you can see one of my projects is also created like yours … only a different area and not that DIY-friendly as it is completely SMT.

If you like to share technical ideas, I am ready to support your efforts.

Merci beaucoup Monsieur Gillet !


I’m really impressed by the ideas, quality and commitment from Olivier in developing and supporting these music machines. I was somewhat reluctant in buying (what I thought was) an obscure synth from an indie manufacturer. Obviously I needn’t have worried. I think both the synths and it’s maker may very well go down in future hall of fames among Moog, ARP, DSI etc

Add me to the list of people thoroughly impressed. I just got my SMR4 MkII Shruthi-1 running last night. I’m absolutely floored by the sounds it can produce. I think part of why it’s so great is it doesn’t try to be anything else. It’s not like a Moog, It’s not like a Sequential / DSI, It’s not like an Oberheim. It has it’s own, very unique character. It might bump my DSI MEK as my favorite synth; I lost track of time, blew at least 2 hours last night playing with it and went to bet at 1:30 A.M. Great job!

Now I’m waiting with bated breath for the Anushri!


or: How I Learned to Stop Worrying and Love the Templates in C++

Yes, analysis of the source code of Shruthi eventually convinced me to use templates in my applications…