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Konstantin Pupkov, Java Developer

Konstantin Pupkov

SoundExpert web site would not exist without skilled project developer and programmer Konstantin Pupkov. He started it from scratch having as a task only some basic ideas of how it should work. When the project was finished it was not only fully operational but, what is very important, well documented.

Currently you see the third generation of SE testing web-service which now utilizes Java-based web components - Portlets 2.0. Thanks to Konstantin transition between SE versions was smooth and seamless, all collected grades were safely transfered during upgrades.

Konstantin Pupkov Resume


Serge Smirnoff, Research Engineer (audio)

Serge Smirnoff

Serge Smirnoff received a degree in electrical engineering from Moscow State University of Technology and finished postgraduate study. A long-standing passion for music, sound and audio technology inspired him to start his own research of perceived audio quality measurements. He has several publications on the subject. SoundExpert Founder.


First of all we would like to thank those people who have ever downloaded and graded a single test file from SoundExpert. And those who support us with mining. Exactly broad participation of site visitors moves this project ahead.

Also SoundExpert would like to thank following people for contribution to the research:

  • Bernhard Feiten, T-Systems (Deutsche Telekom) who kindly found and sent us his old paper "Measuring the Coding Margin of Perceptual Codecs with The Difference Signal" when we were in urgent need for that article.
  • Jacco Dekkers, Philips Research Laboratories for his valuable comments and advices concerning the nature and essence of the Difference level (Df) parameter; exactly thanks to his opinion the expression for Df got its final form.
  • Andrey Merzlyakov, Dmitry Timofeev and Vasily Vasilenko for participation in first laboratory listening tests.



For almost 20 years SoundExpert is the home for innovative audio measurements and research. Newly developed listener-centric audio metric combines instrumental measurements with listening assessments and helps to perform both more efficiently.

Since 2001 more than 10 000 volunteers participated in distributed blind listening tests on Soundexpert website. Sound quality ratings of 100+ codecs were computed thanks to their time and efforts. You can still take part in them.

Recently we developed a new method for instrumental measurements of audio equipment. It is based on the new audio metric and helps to examine technical performance of an audio device in great detail. Furthermore all audio devices can be grouped according to their sound signatures. The measurement procedure was fine-tuned during two years of beta-testing with 30+ portable devices. Now it is mature enough for production environment. First few tested players can be found on Portable players page.

I hope this new audio metric will attract more audio engineers and enthusiasts as it opens new field of audio research where objective and subjective are not separated anymore. Further advance in the research requires many more different audio devices to be tested - a serious challenge for our non-commercial research project. Fortunately portable players are good test subjects for this research, even the old ones. That's why I need some help from our volunteers again. If you have such old/previous/ex digital portable audio player or a smartphone that was marketed as "HQ audio inside", if it is fully functional but not in use anymore, please, consider donating it to SoundExpert. Its df-measurements will appear on the portable players page. Then it will be either kept for research purposes or sold off supporting the project additionally (or given away to some music lover if it can't be sold for some reason). I'm going to refund your postal expenses but can't confirm this right now. Please, contact me for further arrangements.

Manufacturers of portable devices can order df-measurements for their products. The cost of the work will be equal to retail price of the device. I will buy it and perform standard df-measurements. If you decide I will not publish results during a year.

Today building a comprehensive audio quality map of various audio devices on the market can be done by ourselves - audio consumers. And it's not hard indeed. In the end this will free up some time for listening and discussing Music, not technology )).

Serge Smirnoff
SoundExpert Founder