According to wikipedia's definition of stress: That emphasis is typically caused by such properties as increased loudness and vowel length, full articulation of the vowel, and changes in tone.
In English, we can easily detect the increase of loudness of a stressed syllable in contrast to unstressed syllables, while in Russian, the contrast in loudness seems hard, at least for me, to detect. Sometimes the stressed syllable is even less loud than the unstressed syllables, for example in these words:
ржано́й [rʐɨˈnɵj] https://en.wikipedia.org/wiki/File:Ru-%D1%80%D0%B6%D0%B0%D0%BD%D0%BE%D0%B9.ogg
сообража́ть [sʌʌbrʌˈʐatʲ] https://en.wikipedia.org/wiki/File:Ru-%D1%81%D0%BE%D0%BE%D0%B1%D1%80%D0%B0%D0%B6%D0%B0%D1%82%D1%8C.ogg
where the "stress" in terms of loudness is actually moved forward to another syllable. There are countless examples of this.
Anyway, there are other factors that characterize a stress, such as the above mentioned vowel length and full articulation. These factors are clearly possessed by stressed syllables in Russian. Can I say that the larger loudness is not any characteristic to determine a stress, but rather the other factors?
Besides, does the move of stress raise a change of intonation of a word in Russian?