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NEWS Arduino

Interview with Frédéric Meslin from Bonn, a synthesizer shield for Arduino

DFRobot May 06 2016 336

How did you come about the idea for OP·A?

The original idea came from a discussion with an indie developer friend (Thomas Hopper, TACS games) about the feature set of a game console hardware I was designing. Once we soldered the first main-board prototype, had it running, it produced a low-resolution but great video quality. At that point, you could clearly say that not enough thoughts had been thrown into the console audio section and the great video quality was making it tasteless in comparison.

Since I had some contacts at Yamaha and found they still manufacture some FM chips for specific needs, I naturally got in touch with them. Though, communication was lost when I told them the nature of the project.

So being pushed by friends, I set myself the challenge to design an equivalent chip in a short time-span. That was not easy because my day job at the time was writing the audio engine of the Waldorf Music NW1 wavetable module. Both activities were kind of conflicting and I was giving full priority to Waldorf projects.

The idea of making it a shield came later, when I realize I could not really demonstrate and test the chip functionalities without having a simple and standard device that would make use of it. The chip has been designed around a serial interface for transferring sound data and playing notes. To troubleshoot communication problems, I was not using anexpensive logic analyzer but a stock Arduino board.

It quickly come clear that an Arduino board could be a great host for that chip. So I had a look at alternative solutions and I could only find projects using original Yamaha chips snatched off old hardware. I wanted to build something based on available components.


What was the most difficult aspect of prototyping the OP·A?

The most difficult aspect was to make the shield as cheap as possible while keeping high audio quality standard. And that was not granted. There are many noisy and glitchy circuits around and, having some experience in designing consumer audio products, I wanted something better for the future users. So I went on a rather long prototyping journey, making 4 revisions of PCB, spending hundred of hours on the software to end up with a quite simple design. But many options have been compared and evaluated.

Another difficulty of this project is its brand range of activities. The board had to be developed, the DSP software, the software editor (for 3 different operating systems), the documentation … It represents quite a challenge.

When did you feel like the prototype was finished?

Never. As an engineer, you’re never satisfied with a design because there is always room for improvement. And you always see the weakest parts. In French we have a proverb that’s says “Best is the good worse enemy”. I declared the prototype finished when I started to see friends having fun with the shield and no longer complaining about issues!

The real answer is: when USB ground loops and USB power noise injection problems were fixed. Which was the case in the last iteration.

What aspects of manufacturing the OP·A are you looking forward to?

Assuredly production tests. I want everyone receiving a fully working shield and I cannot try them one by one personally. So I need to build an electronic system which will quickly measure the shield output and check the communication with the DSP. I guess using an Arduino board.

Do you foresee hardware startups in music becoming popular in the coming years?

There are many already and some got reasonably notorious. I am thinking about u-he, Bitwig, Teenage Engineering, Roli, Mutable instruments … and only speaking about the synth / audio production domain. Have a look at the guitar / bass, the PA departments, it seems similar …

I have the personal feeling that the audio market is saturated. And this market is conservative. I do not know what will be the future of these companies in the next five years perspective. It will also depend on the evolution of our consumption habits. I have the feeling that musicians
of today tend to be attracted by boutique instruments and devices. To get something unique / custom made. If this tendency is sustained, it may give many people a steady job.

Any plans to expand the OP·A once the kickstarter is completed?

Possibly, if this project can cover the production costs, I drew a line over the development cost, I would like to design a product more live performance orientated using the same technology and tools underneath. Or finishing the game console, who knows?

Back now on Kickstarter

by alistair via Techmog