How to support SoundExpert

Let's be honest – there are no any "free ratings" in real-world because quality control is paid either by production side or by consuming side. SoundExpert is made for-and-by audio consumers and is not affiliated with any audio manufacturers/developers. It works only thanks to audio enthusiasts who contribute their attention, time and efforts. Fortunately the internet and human distributed projects can utilize such efforts, even the smallest ones, very efficiently for achieving great goals. The goal of SoundExpert is to create publicly available mechanism for objective measurements of perceived sound quality of various audio equipment and technologies.

If you like the idea of consumer control over audio quality measurements and how this idea is implemented on the site, you can make your contribution to further research and development of the project.

Any your assistance will be gratefully received whether it is time and effort consuming like contributing to research process or easy and simple as a click of a mouse on a right place of the site. Here is some of the choices:

  • Contribute a fraction of your computing power   
  • Download and grade a test file
  • Grant equipment
  • Make a donation

Other ideas might still be in your head. Your proposals are accepted. Feel free to contact us.



Donate your old player

If you have an 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). Please, contact us 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. The latter will be bought and measured according to df-metric. If you decide the results will not be published during a year.



Download and grade a test file

Downloading and grading a test file in SE listening tests is still a valuable contribution. We'll be thankful for a single test file. Five or ten files will be a serious contribution to the project. Regardless of the fact that each rating needs minimum 300 returned grades in order to be reliable, we don't recommend grading more than 10 files at a time because of possible listening fatigue. Please, visit our "Listening Tests" page and follow three easy steps to participate.

Participate in Listening Tests



Measurement equipment

Grant equipment

As SoundExpert is non-commercial independent research project we can´t afford buying expensive laboratory equipment. At the moment we need high-precision D/A and A/D converters which will allow to start objective measurements and listening tests of high quality audio equipment both digital and analog.

Basic features and specifications required:

  • Simultaneous input and output conversions with synchronized clock
  • Standard balanced and unbalanced analogue inputs/outputs
  • USB or FireWire digital input/output
  • Sampling frequency (fs) up to 192 kHz
  • Total (D+A) accuracy of both conversions:
    • THD+Noise: < -100 dB
    • Frequency response: ± 0.1 db within 0….1/2fs
    • Amplitude accuracy: ± 1% within 0….1/2fs
    • Phase accuracy: ± 1.0 degree within 0….1/2fs

We will receive such laboratory instrument with gratitude and this fact will be mentioned on SoundExpert site specially. Please, contact us for details.


Make a donation

We will do our best to maintain the project alive and up-to-date as we did it since 2001. Wherever it is possible we try to use free and open source products in our work. All other expenses, including testing equipment and web hosting, are covered by SE authors privately. If you like to share some of these expenses with us you can donate any amount using the options below. Thank you!



SE Bitcoin QR code

Specify amount in Rubles
(auto conversion from your currency)
Donate with your card
$10 ≈ R700
(current rate at