Subject: Re: sound events database From: Neil Waterman <neil.waterman@xxxxxxxx> Date: Thu, 22 Apr 2010 11:10:13 -0400 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>--Apple-Mail-6--563446130 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Hi Ernesto, Over many years we have built up a library of recordings made in and around aircraft that provide the guidance levels we need for these more generic traffic sounds. These are calibrated using cal tones on each recording. Even having this information does not stop pilots from making subjective requests to make certain sound cues louder or softer based on their perception - this is often due to personal experience with a particular situation by that specific pilot. For example KLM at Schipol (Amsterdam) airport may use a particular type of pushback truck, one that is different from our standard sound reference, and hence, despite the fact I have aircraft recordings with calibration tones, etc, of a similar pushback vehicle, I will be requested to retune the sound either louder or quieter as requested. Unfortunately I'm not personally aware of a single consolidated database that will provide a wide-range of sound events and corresponding SPL/distance figures, but there may be others on the list that have suggestions. Regards, Neil On Apr 22, 2010, at 10:33 AM, Ernesto Accolti wrote: > Dear Neil. > > You are right. Both, the sound events database and an SPL at known > distances database can be sufficient. However I'm not sure if it is > easy to access to this two databases and adapt each data or making > myself the (calibrated) recordings. > I think that I will need more than 100 sound events. > > How did you solved the problem of the ground traffic? Did you had to > measure yourself the typical SPL at known distances? > > Thanks! > > Ernesto. > > > 2010/4/22 Neil Waterman <neil.waterman@xxxxxxxx>: >> Surely what you really need is a database of typical SPL levels >> for certain >> sound sources at known distances? >> I work for a company producing Level D certifiable sound systems >> for use in >> the highest fidelity sound systems, and reproduction must EXACTLY >> match the >> source aircraft, but once you accept general sounds (as opposed to >> SPECIFIC >> ones) there is no reference SPL only representative levels - I >> face this >> problem when representing the ground traffic around the aircraft >> while on >> the ground (push-back trucks, luggage carts, etc) >> - Neil > --Apple-Mail-6--563446130 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=US-ASCII <html><body style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; = -webkit-line-break: after-white-space; "><div><span = class=3D"Apple-style-span" style=3D"border-collapse: separate; color: = rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: = normal; font-variant: normal; font-weight: normal; letter-spacing: = normal; line-height: normal; orphans: 2; text-align: auto; text-indent: = 0px; text-transform: none; white-space: normal; widows: 2; 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; ">Hi = Ernesto,</span></div><div><br></div><div><span class=3D"Apple-style-span" = style=3D"border-collapse: separate; color: rgb(0, 0, 0); font-family: = Helvetica; font-size: 12px; font-style: normal; font-variant: normal; = font-weight: normal; letter-spacing: normal; line-height: normal; = orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; = white-space: normal; widows: 2; 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; ">Over many years we have built up a = library of recordings made in and around aircraft that provide the = guidance levels we need for these more generic traffic sounds. These are = calibrated using cal tones on each = recording.</span></div><div><br></div><div><span = class=3D"Apple-style-span" style=3D"border-collapse: separate; color: = rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: = normal; font-variant: normal; font-weight: normal; letter-spacing: = normal; line-height: normal; orphans: 2; text-align: auto; text-indent: = 0px; text-transform: none; white-space: normal; widows: 2; 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; ">Even having this information does = not stop pilots from making subjective requests to make certain sound = cues louder or softer based on their perception - this is often due to = personal experience with a particular situation by that specific pilot. = For example KLM at Schipol (Amsterdam) airport may use a particular type = of pushback truck, one that is different from our standard sound = reference, and hence, despite the fact I have aircraft recordings with = calibration tones, etc, of a similar pushback vehicle, I will be = requested to retune the sound either louder or quieter as requested.<br = class=3D"Apple-interchange-newline"></span><br = class=3D"Apple-interchange-newline"> </div><div>Unfortunately I'm not = personally aware of a single consolidated database that will provide a = wide-range of sound events and corresponding SPL/distance figures, but = there may be others on the list that have = suggestions.</div><div><br></div><div>Regards, = Neil</div><br><div><div>On Apr 22, 2010, at 10:33 AM, Ernesto Accolti = wrote:</div><br class=3D"Apple-interchange-newline"><blockquote = type=3D"cite"><div style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; ">Dear Neil.</div><div = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; min-height: 14px; "><br></div><div style=3D"margin-top: = 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">You are = right. Both, the sound events database and an SPL at known</div><div = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; ">distances database can be sufficient. However I'm = not sure if it is</div><div style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; ">easy to access to this two = databases and adapt each data or making</div><div style=3D"margin-top: = 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">myself = the (calibrated) recordings.</div><div style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I think that = I will need more than 100 sound events.</div><div style=3D"margin-top: = 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; = min-height: 14px; "><br></div><div style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">How did you = solved the problem of the ground traffic? Did you had to</div><div = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; ">measure yourself the typical SPL at known = distances?</div><div style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; ">Thanks!</div><div style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: = 14px; "><br></div><div style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; ">Ernesto.</div><div = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; min-height: 14px; "><br></div><div style=3D"margin-top: = 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; = min-height: 14px; "><br></div><div style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">2010/4/22 = Neil Waterman <<a = href=3D"mailto:neil.waterman@xxxxxxxx">neil.waterman@xxxxxxxx</a>&= gt;:</div> <blockquote type=3D"cite"><div style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Surely what = you really need is a database of typical SPL levels for = certain</div><div style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; ">sound sources at known = distances?</div><div style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; ">I work for a company producing = Level D certifiable sound systems for use in</div><div = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; ">the highest fidelity sound systems, and reproduction = must EXACTLY match the</div><div style=3D"margin-top: 0px; margin-right: = 0px; margin-bottom: 0px; margin-left: 0px; ">source aircraft, but once = you accept general sounds (as opposed to SPECIFIC</div><div = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; ">ones) there is no reference SPL only representative = levels - I face this</div><div style=3D"margin-top: 0px; margin-right: = 0px; margin-bottom: 0px; margin-left: 0px; ">problem when representing = the ground traffic around the aircraft while on</div><div = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; ">the ground (push-back trucks, luggage carts, = etc)</div><div style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; ">- Neil</div> </blockquote><div = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; min-height: 14px; "><br></div> = </blockquote></div><br></body></html>= --Apple-Mail-6--563446130--