sˈɪns ˈiːkwəllˈaʊdnəs kˈɜːvz dᵻpˈɛnd nˌɑːt ˈoʊnli ɔnðɪ ˌɪndᵻvˈɪdʒuːəl bˌʌt ˈɔːlsoʊ ɔnðə vˈɑːljuːm æt wˌɪtʃ ðə nˈɔɪz ɪz plˈeɪd bˈæk, ðɛɹ ɪz nˈoʊwˈʌn tɹˈuː ɡɹˈeɪ nˈɔɪz.
Since equal-loudness curves depend not only on the individual but also on the volume at which the noise is played back, there is no one true grey noise.