Subject: Re: [AUDITORY] Psychoacoustics with active-noise cancelling headphones From: =?UTF-8?Q?Marcin_Wr=C3=B3blewski?= <wmarcin@xxxxxxxx> Date: Thu, 20 Sep 2018 09:53:10 -0700 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>--000000000000ddbd260576505dac Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Guillaume, I would discourage you from using active noise cancelling headphones for psychoacoustic experiments due to their unpredictable nature -- the noise attenuation typically involves some phase inversion of the surrounding background noise (your stimuli are not immune to that), they are really only efficient for lower frequencies, and their output will change with the change in the background noise. Ensuing is the loss of experimental control. Instead, you could use insert earphones (as Neil suggested) and use earmuffs designed for hearing protection over the insert phones. You'll get greater combined attenuation than from any active noise attenuating headphones, and no unpredictability associated with the use of the latter. marcin * We must not forget that when radium was discovered no one knew that it would prove useful in hospitals. The work was one of pure science. And this is a proof that scientific work must not be considered from the point of view of the direct usefulness of it. It must be done for itself, for the beauty of science, and then there is always the chance that a scientific discovery may become like the radium a benefit for mankind. * *Maria Sk=C5=82odowska-Curie* On Mon, Sep 17, 2018 at 11:19 PM Guillaume Lemaitre < guillaumejlemaitre@xxxxxxxx> wrote: > Dear list, > I would like to know if someone has ever tried to conduct a > psychoacoustics experiment with active-noise cancelling headphones. > I am wondering whether existing devices would be good enough to cancel ou= t > a wideband background noise (such as a train interior noise) and playback > stimuli with sufficient accuracy. > I have been happy with insert earphones for experiments within an MRI > scanner, but I wonder if less expensive consumer audio devices could do t= he > job for environmental background noises. > Many thanks ! > Guillaume Lemaitre > > --000000000000ddbd260576505dac Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable <div dir=3D"ltr"><div class=3D"gmail_default" style=3D"font-family:tahoma,s= ans-serif">Hi Guillaume,</div><div class=3D"gmail_default" style=3D"font-fa= mily:tahoma,sans-serif"><br></div><div class=3D"gmail_default" style=3D"fon= t-family:tahoma,sans-serif">I would discourage you from using active noise = cancelling headphones for psychoacoustic experiments due to their unpredict= able nature -- the noise attenuation typically involves some phase inversio= n of the surrounding background noise (your stimuli are not immune to that)= , they are really only efficient for lower frequencies, and their output wi= ll change with the change in the background noise.=C2=A0 Ensuing is the los= s of experimental control.=C2=A0=C2=A0</div><div class=3D"gmail_default" st= yle=3D"font-family:tahoma,sans-serif"><br></div><div class=3D"gmail_default= " style=3D"font-family:tahoma,sans-serif">Instead, you could use insert ear= phones (as Neil suggested) and use earmuffs designed for hearing protection= over the insert phones.=C2=A0 You'll get greater combined attenuation = than from any active noise attenuating headphones, and no unpredictability = associated with the use of the latter.</div><div class=3D"gmail_default" st= yle=3D"font-family:tahoma,sans-serif"><br></div><div class=3D"gmail_default= " style=3D"font-family:tahoma,sans-serif">marcin</div><div><div dir=3D"ltr"= class=3D"gmail_signature" data-smartmail=3D"gmail_signature"><div dir=3D"l= tr"><font style=3D"color:rgb(51,51,255)"><br><br><em><font size=3D"2"><u>= =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 = =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 = =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 = =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0=C2=A0</u><br= ><font face=3D"times new roman,serif" size=3D"1">We must not forget that wh= en radium was discovered no one knew that it=20 would prove useful in hospitals. The work was one of pure science. And=20 this is a proof that scientific work must not be considered from the=20 point of view of the direct usefulness of it. It must be done for=20 itself, for the beauty of science, and then there is always the chance=20 that a scientific discovery may become like the radium a benefit for=20 mankind.</font>=C2=A0 </font></em></font><br><u style=3D"color:rgb(0,0,153)= "><i style=3D"font-family:garamond,serif">Maria Sk=C5=82odowska-Curie</i></= u><br></div></div></div><br></div><br><div class=3D"gmail_quote"><div dir= =3D"ltr">On Mon, Sep 17, 2018 at 11:19 PM Guillaume Lemaitre <<a href=3D= "mailto:guillaumejlemaitre@xxxxxxxx">guillaumejlemaitre@xxxxxxxx</a>> = wrote:<br></div><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8e= x;border-left:1px #ccc solid;padding-left:1ex"><div dir=3D"ltr"><div><div><= div><div><div>Dear list,<br></div>I would like to know if someone has ever = tried to conduct a psychoacoustics experiment with active-noise cancelling = headphones. <br></div>I am wondering whether existing devices would be good= enough to cancel out a wideband background noise (such as a train interior= noise) and playback stimuli with sufficient accuracy.<br></div>I have been= happy with insert earphones for experiments within an MRI scanner, but I w= onder if less expensive consumer audio devices could do the job for environ= mental background noises.<br></div>Many thanks !<br></div>Guillaume Lemaitr= e<br><div><br></div></div> </blockquote></div> --000000000000ddbd260576505dac--