Subject: unsubscribe From: Thomas Guignard <t-guignard@xxxxxxxx> Date: Fri, 21 Nov 2008 11:30:02 +0100 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>--_2ac427fc-33fa-4e72-b408-a6dc7d5cc0e4_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Dear Madam or Sir=2C I would like to stop becoming email from this list. Please could you take my name ''Thomas Guignard'' under the email ''t-guign= ard@xxxxxxxx" off the list. Best regards=2C Thomas Guignard > Date: Fri=2C 14 Nov 2008 11:43:50 +0100 > From: auditorylist@xxxxxxxx > Subject: HRTF failure > To: AUDITORY@xxxxxxxx >=20 > Dear List=2C >=20 > We encounter a problem when trying to place a sound at a virtual=20 > position in space by means of head related transfer functions (HRTF). >=20 > We use sounds from the IAPS database (International Affective Digitized=20 > Sounds System=2C Bradley & Lang) as well as simple white noise of six=20 > seconds duration. We use the Kemar HRTF=2C the "compact data" with zero=20 > elevation. We convolve the original sound data with the HRTF data as=20 > suggested in the documentation. The final sounds are presented using=20 > Beyer Dynamic DT770 headphones. >=20 > We have tested the precision with which our sounds are placed in virtual= =20 > space=2C by presenting them to eight listeners. The listeners had a=20 > touchscreen lying on their lap=2C with a circle plotted on it=2C and they= =20 > could indicated the direction where they perceived that the sound came=20 > from. We presented to them in total 144 sounds=2C 72 noises and 72 IAPS=20 > sounds=2C coming from 36 virtual directions (0=B0=2C 10=B0=2C 20=B0...) i= n=20 > randomized order. >=20 > The results are shown in a figure that I put in the internet: > http://www.uni-kiel.de/psychologie/emotion/hrtf/direction.gif > The red dots are from IAPS sounds=2C the yellow dots are from the noises.= =20 > The x-axis shows the "true" (virtual) angle=2C the y-axis shows the=20 > estimated angle. As can be seen in this figure=2C listeners could well=20 > discriminate between sounds from the left and sounds from the right. But= =20 > not more than that. There is a certain reduction of variance for sounds=20 > coming from 90=B0 and from 270=B0=2C but there is no correlation with ang= le=20 > within one hemifield. >=20 > Now we are eager to learn from you: What could be the cause for this=20 > failure? >=20 > A) HRTFs are not better than that. > B) The headphones are inadequate. > C) It must be a programming error (we don't think so) > D) .... >=20 > We are grateful for any help in interpreting the possible cause for this= =20 > failure. >=20 > Thank you very much in advance=2C > Chris >=20 > --=20 > Christian Kaernbach > Christian-Albrechts-Universit=E4t zu Kiel > Germany > www.kaernbach.de _________________________________________________________________ Connect to the next generation of MSN Messenger=A0 http://imagine-msn.com/messenger/launch80/default.aspx?locale=3Den-us&sourc= e=3Dwlmailtagline= --_2ac427fc-33fa-4e72-b408-a6dc7d5cc0e4_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable <html> <head> <style> .hmmessage P { margin:0px=3B padding:0px } body.hmmessage { font-size: 10pt=3B font-family:Verdana } </style> </head> <body class=3D'hmmessage'> Dear Madam or Sir=2C<br><br>I would like to stop becoming email from this l= ist.<br>Please could you take my name <b>''Thomas Guignard''</b> under the = email <b>''t-guignard@xxxxxxxx"</b> off the list.<br><br>Best regards=2C<= br>Thomas Guignard<br><br>>=3B Date: Fri=2C 14 Nov 2008 11:43:50 +0100<br= >>=3B From: auditorylist@xxxxxxxx<br>>=3B Subject: HRTF failure<br>= >=3B To: AUDITORY@xxxxxxxx<br>>=3B <br>>=3B Dear List=2C<br>&g= t=3B <br>>=3B We encounter a problem when trying to place a sound at a vi= rtual <br>>=3B position in space by means of head related transfer functi= ons (HRTF).<br>>=3B <br>>=3B We use sounds from the IAPS database (Inte= rnational Affective Digitized <br>>=3B Sounds System=2C Bradley &=3B L= ang) as well as simple white noise of six <br>>=3B seconds duration. We u= se the Kemar HRTF=2C the "compact data" with zero <br>>=3B elevation. We = convolve the original sound data with the HRTF data as <br>>=3B suggested= in the documentation. The final sounds are presented using <br>>=3B Beye= r Dynamic DT770 headphones.<br>>=3B <br>>=3B We have tested the precisi= on with which our sounds are placed in virtual <br>>=3B space=2C by prese= nting them to eight listeners. The listeners had a <br>>=3B touchscreen l= ying on their lap=2C with a circle plotted on it=2C and they <br>>=3B cou= ld indicated the direction where they perceived that the sound came <br>>= =3B from. We presented to them in total 144 sounds=2C 72 noises and 72 IAPS= <br>>=3B sounds=2C coming from 36 virtual directions (0=B0=2C 10=B0=2C 2= 0=B0...) in <br>>=3B randomized order.<br>>=3B <br>>=3B The results a= re shown in a figure that I put in the internet:<br>>=3B http://www.un= i-kiel.de/psychologie/emotion/hrtf/direction.gif<br>>=3B The red dots are= from IAPS sounds=2C the yellow dots are from the noises. <br>>=3B The x-= axis shows the "true" (virtual) angle=2C the y-axis shows the <br>>=3B es= timated angle. As can be seen in this figure=2C listeners could well <br>&g= t=3B discriminate between sounds from the left and sounds from the right. B= ut <br>>=3B not more than that. There is a certain reduction of variance = for sounds <br>>=3B coming from 90=B0 and from 270=B0=2C but there is no = correlation with angle <br>>=3B within one hemifield.<br>>=3B <br>>= =3B Now we are eager to learn from you: What could be the cause for this <b= r>>=3B failure?<br>>=3B <br>>=3B A) HRTFs are not better than that.<b= r>>=3B B) The headphones are inadequate.<br>>=3B C) It must be a progra= mming error (we don't think so)<br>>=3B D) ....<br>>=3B <br>>=3B We a= re grateful for any help in interpreting the possible cause for this <br>&g= t=3B failure.<br>>=3B <br>>=3B Thank you very much in advance=2C<br>>= =3B Chris<br>>=3B <br>>=3B -- <br>>=3B Christian Kaernbach<br>>=3B = Christian-Albrechts-Universit=E4t zu Kiel<br>>=3B Germany<br>>=3B www.k= aernbach.de<br><br /><hr />Connect to the next generation of MSN Messenger= =A0 <a href=3D'http://imagine-msn.com/messenger/launch80/default.aspx?loca= le=3Den-us&source=3Dwlmailtagline' target=3D'_new'>Get it now! </a></body> </html>= --_2ac427fc-33fa-4e72-b408-a6dc7d5cc0e4_--
