Subject: From: Scott Pennock <SPennock@xxxxxxxx> Date: Mon, 18 Jan 2010 12:40:09 -0500 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>This is a multi-part message in MIME format. ------_=_NextPart_001_01CA9865.484F9228 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable Hi Neil, =20 The tolerance for delay will depend on the loss in the sidetone path. You can find some relevant information in Figure 1/G.131 of ITU-T Recommendation G.131. This document can be downloaded free of charge at: http://www.itu.int/rec/T-REC-G.131-200311-I =20 Just be careful about the generalizability of these results to your application (e.g., tolerance could be different for wider bandwith speech). =20 Best regards, Scott Pennock QNX Software Systems ________________________________ From: AUDITORY - Research in Auditory Perception [mailto:AUDITORY@xxxxxxxx On Behalf Of Neil Waterman Sent: January 18, 2010 11:19 AM To: AUDITORY@xxxxxxxx Subject:=20 Hello all, I was pointed to this list from the friendly folk over at the SurSound (surround sound list) as my question will hopefully sit more comfortably with the expertise here, but as a newbie here I'll preface my question with a preemptive apology if I am at all off-topic for the list focus. Here's my question: I have been attempting to track down any research directed toward human perception of delay in local sidetone. Specifically I am trying to find any work investigating perception of very short delays when using fully digital systems that return sidetone via the digital signal chain (mic --> A/D --> processing system --> D/A --> headset). An example might be the use of a fully digital communications system within an aircraft, where the processing system is the aircraft communications equipment. When the crew talk on a radio, they expect to hear themselves via sidetone (this confirms the radio is working for one thing).=20 Although searching high and low, I have been unable to find anything useful regarding tolerance to delay. It seems most of what I can find refers to VoIP systems, where the latency issues appear to be much longer than those I am considering. In the limited work I can, find most dismiss delays in the sub-20mS as being below human perception, however I have evidential proof that this is plainly wrong. If anyone has any suggestions for research that covers sidetone delay in the sub-20mS region I would be extremely grateful. Thanks in advance for any and all input. - Neil ------_=_NextPart_001_01CA9865.484F9228 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META content=3D"text/html; charset=3Dus-ascii" = http-equiv=3DContent-Type> <META name=3DGENERATOR content=3D"MSHTML 8.00.6001.18854"></HEAD> <BODY=20 style=3D"WORD-WRAP: break-word; -webkit-nbsp-mode: space; = -webkit-line-break: after-white-space"> <DIV dir=3Dltr align=3Dleft><SPAN class=3D621203017-18012010><FONT = color=3D#0000ff=20 size=3D2 face=3DArial>Hi Neil,</FONT></SPAN></DIV> <DIV dir=3Dltr align=3Dleft><SPAN class=3D621203017-18012010><FONT = color=3D#0000ff=20 size=3D2 face=3DArial></FONT></SPAN> </DIV> <DIV dir=3Dltr align=3Dleft><SPAN class=3D621203017-18012010><FONT = color=3D#0000ff=20 size=3D2 face=3DArial>The tolerance for delay will depend on the loss in = the=20 sidetone path. You can find some relevant information in Figure 1/G.131=20 of ITU-T Recommendation G.131. This document can be=20 downloaded free of charge at: <A=20 href=3D"http://www.itu.int/rec/T-REC-G.131-200311-I">http://www.itu.int/r= ec/T-REC-G.131-200311-I</A></FONT></SPAN></DIV> <DIV dir=3Dltr align=3Dleft><SPAN class=3D621203017-18012010><FONT = color=3D#0000ff=20 size=3D2 face=3DArial></FONT></SPAN> </DIV> <DIV dir=3Dltr align=3Dleft><SPAN class=3D621203017-18012010><FONT = color=3D#0000ff=20 size=3D2 face=3DArial>Just be careful about the generalizability of = these results to=20 your application (e.g., tolerance could be different for wider bandwith=20 speech).</FONT></SPAN></DIV> <DIV dir=3Dltr align=3Dleft><SPAN = class=3D621203017-18012010></SPAN> </DIV> <DIV dir=3Dltr align=3Dleft><SPAN class=3D621203017-18012010><FONT = color=3D#0000ff=20 size=3D2 face=3DArial>Best regards,</FONT></SPAN></DIV> <DIV dir=3Dltr align=3Dleft><SPAN class=3D621203017-18012010><FONT = color=3D#0000ff=20 size=3D2 face=3DArial>Scott Pennock</FONT></SPAN></DIV> <DIV dir=3Dltr align=3Dleft><SPAN class=3D621203017-18012010><FONT = color=3D#0000ff=20 size=3D2 face=3DArial>QNX Software Systems</FONT></SPAN></DIV><BR> <DIV dir=3Dltr lang=3Den-us class=3DOutlookMessageHeader align=3Dleft> <HR tabIndex=3D-1> <FONT size=3D2 face=3DTahoma><B>From:</B> AUDITORY - Research in = Auditory Perception=20 [mailto:AUDITORY@xxxxxxxx <B>On Behalf Of </B>Neil=20 Waterman<BR><B>Sent:</B> January 18, 2010 11:19 AM<BR><B>To:</B>=20 AUDITORY@xxxxxxxx<BR><B>Subject:</B> <BR></FONT><BR></DIV> <DIV></DIV> <DIV><SPAN=20 style=3D"WIDOWS: 2; TEXT-TRANSFORM: none; TEXT-INDENT: 0px; = BORDER-COLLAPSE: separate; FONT: 12px Helvetica; WHITE-SPACE: normal; = ORPHANS: 2; LETTER-SPACING: normal; COLOR: rgb(0,0,0); WORD-SPACING: = 0px; -webkit-border-horizontal-spacing: 0px; = -webkit-border-vertical-spacing: 0px; = -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: = auto; -webkit-text-stroke-width: 0"=20 class=3DApple-style-span><SPAN=20 style=3D"WIDOWS: 2; TEXT-TRANSFORM: none; TEXT-INDENT: 0px; = BORDER-COLLAPSE: separate; FONT: 12px Helvetica; WHITE-SPACE: normal; = ORPHANS: 2; LETTER-SPACING: normal; COLOR: rgb(0,0,0); WORD-SPACING: = 0px; -webkit-border-horizontal-spacing: 0px; = -webkit-border-vertical-spacing: 0px; = -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: = auto; -webkit-text-stroke-width: 0px"=20 class=3DApple-style-span> <DIV>Hello all,</DIV> <DIV><BR></DIV> <DIV>I was pointed to this list from the friendly folk over at the = SurSound=20 (surround sound list) as my question will hopefully sit more comfortably = with=20 the expertise here, but as a newbie here I'll preface my question with a = preemptive apology if I am at all off-topic for the list focus.</DIV> <DIV><BR></DIV> <DIV>Here's my question:</DIV> <DIV><BR></DIV> <DIV> <DIV style=3D"MARGIN: 0px">I have been attempting to track down any = research=20 directed toward human perception of delay in local sidetone. = Specifically I am=20 trying to find any work investigating perception of very short delays = when using=20 fully digital systems that return sidetone via the digital signal chain = (mic=20 --> A/D --> processing system --> D/A --> headset).</DIV> <DIV style=3D"MARGIN: 0px; MIN-HEIGHT: 14px"><BR></DIV> <DIV style=3D"MARGIN: 0px">An example might be the use of a fully = digital=20 communications system within an aircraft, where the processing system is = the=20 aircraft communications equipment. When the crew talk on a radio, they = expect to=20 hear themselves via sidetone (this confirms the radio is working for one = thing). </DIV> <DIV style=3D"MARGIN: 0px; MIN-HEIGHT: 14px"><BR></DIV> <DIV style=3D"MARGIN: 0px">Although searching high and low, I have been = unable to=20 find anything useful regarding tolerance to delay. It seems most of what = I can=20 find refers to VoIP systems, where the latency issues appear to be much = longer=20 than those I am considering.</DIV> <DIV style=3D"MARGIN: 0px; MIN-HEIGHT: 14px"><BR></DIV> <DIV style=3D"MARGIN: 0px">In the limited work I can, find most dismiss = delays in=20 the sub-20mS as being below human perception, however I have evidential = proof=20 that this is plainly wrong. If anyone has any suggestions for research = that=20 covers sidetone delay in the sub-20mS region I would be extremely=20 grateful.</DIV> <DIV style=3D"MARGIN: 0px"><BR></DIV> <DIV style=3D"MARGIN: 0px">Thanks in advance for any and all = input.</DIV> <DIV style=3D"MARGIN: 0px"><BR></DIV> <DIV style=3D"MARGIN: 0px">- Neil</DIV></DIV></SPAN><BR=20 class=3DApple-interchange-newline></SPAN><BR=20 class=3DApple-interchange-newline></DIV><BR></BODY></HTML> ------_=_NextPart_001_01CA9865.484F9228--