Publication date: 
The selected musical composition and the sound of the Škoda Superb electric car had to be synthesized by students who competed in the seventh year of the Synth Challenge competition organized by CTU Faculty of Electrical Engineering and partners. The winner was Tomáš Chaloupecký, a student of the Master's degree programme Cybernetics and Robotics. The expert jury appreciated especially his successful programming of the composition Typewriter by the American composer Leroy Anderson.

You can listen to the composition synthesized by Chaloupecký here. The results of the Synth Challenge 2022 were officially announced on 11 January 2023 at FEL in Prague 6 - Dejvice. While synthesizing the sound of an electric car was compulsory for everyone, the contestants had a freer hand in choosing the song. They could either tackle the aforementioned Typewriter, where the typewriter is a full-fledged musical instrument, or the well-known piece Barcarolle from the opera The Tales of Hoffmann by French composer Jacques Offenbach. Twenty-one male and female students participated in Synth Challenge 2022, an increase of 13 students year-over-year.

"All the entries were very nice. It was difficult for us to choose the best ones," said the main organiser of the competition, Professor Roman Čmejla. Chaloupecký's version of Typewriter was described as excellent by Čmejla, who works at the FEL's Department of Circuit Theory.

The experiments that led to success and the natural sound of the car

"I started with a piano piece because it was closer to my heart. First I tried an orchestral version, which failed completely," Chaloupecký described the process of creation. "Gradually I chose the right instruments. I synthesized the individual instruments to make the individual notes sound good, transposed part of the piece to fit better into the frequency range for that instrument," added the winner, who used the sound of the bass guitar alongside the piano for his successful project.

"And for more technical sounds, like the stroke of a typewriter, I just studied what the spectra of existing recordings and sounds roughly looked like, and I tried to imitate those. Using the frequency method, I then tried to interleave the spectra. It was more of a trial and error as to what would actually sound good," said Chaloupecký, who programmed the audio synthesis algorithms in MATLAB. Contestants could use any other programming environment, however. The winner also recalled a curiosity that occurred while working on the sound of a car - with a bug in the code, according to Chaloupecký, it sounded better than after he fixed it.

Josef Hůla, a student of the Electronics and Communication programme, won the silver medal. Hůla scored with his synthesis of the sound of an electric car. Doc. Petr Bouchner, from Faculty of Transportation Sciences of Czech Technical University, who was one of the judges, appreciated the resulting sound as natural and complex.

"I enjoyed it because I'm quite interested in physical modelling and I approached it that way. So I gradually divided up the sound sources and looked for the ideal way to model them," said Hůla. "I broke it down into individual tracks. Like just the sound of the wind around the car, the sounds of the tires, the engine and the brakes. Then I did a final mix and weighted the individual tracks. And just by ear, I adjusted the weights to make it feel as natural as possible," the contestant concluded. Of the tracks, Hůla chose Barcarolle. You can listen to his version here.

And Jiří Šmíd, who finished third, chose the same song. According to the organizers, the student of the Electronics and Communication study program won the bronze because he worked out the sound of the electric carBarcarolle, and also prepared a good report.

Synth Challenge is also for high school students

The Synth Challenge competition is a symbolic end of the semester course Synthesis of Audio Signals taught by Professor Čmejla. However, the competition itself is also open to male and female students from other universities and now also to high school students.

Due to the high quality of their performances, five students also received honorable mentions from the jury. They are Markéta Kvašová, Tereza Uhrová, Sam Espallac, Louis Kälble and Mikhail Poludin. You can listen to the works of all the contestants on the website.

In previous years, the students had to synthesize, among others, Queen's 'Bohemian Rhapsody', Smetana's 'Vltava', 'Yellow Submarine' by the Beatles or the theme tune of the British crime series Murder in Midsomer. The competition songs from all past editions are on-line as well.

The partners of the competition are CTU Faculty of Transport Sciences, the CTU Czech Institute of Informatics, Robotics and Cybernetics, the Czech Acoustical Society and the software company Humusoft.