Ah, that's becoming clearer, thanks. In respect of trying to measure precedence, then naturally, I'd say that without transients, one has something which would not appeal well to precedence effects anyway - (in the Franssen effect, which uses sinewaves as stimuli, I believe, it was shown that no re-localisation occurred even when panned through 180 degrees - until a transient is put in).
But in respect of summing localisation (which, strictly, comes under the heading of Precedence effects) - I still think you need the transient content, otherwise, what is it that one is summing? - noise with a temporal offset is becoming decorrelated (I'm not talking about how it might generate lower interaural cross-correlation, obviously) but essentially has no source direction because it's not a source, if you see what I mean I'll look the paper up cheers Dr. Peter Lennox Senior Lecturer in Perception College of Arts University of Derby, UK e: [email protected] t: 01332 593155 https://derby.academia.edu/peterlennox https://www.researchgate.net/profile/Peter_Lennox -----Original Message----- From: Sursound [mailto:[email protected]] On Behalf Of Jörn Nettingsmeier Sent: 09 December 2015 14:00 To: Surround Sound discussion group <[email protected]> Subject: [Sursound] vertical precendence and summing localisation (wallis and lee 2015) On 12/08/2015 09:07 PM, Peter Lennox wrote: > no -percedence effects include a range of phenomena. But precedence in > the median plane isn't quite as effective as in the azimuthal plane, > according to Litovsky, Rakerd, Hartmann et al, but is still quite > effective and so not negligible. So I'd like to understand what Lee > (Huddersfield) was saying, to compare. i've attached the paper, since it is open access. i guess i misrepresented it a bit, because i was being sloppy about distinguishing between precedence effect and summing localisation. however, wallis and lee conclude: "Additionally, no evidence could be found to support the operation of the precedence effect in median plane stereophony. In the present study the only occasions whereby stimuli were localized at the position of the ear- lier emitting loudspeaker were due to the pitch height ef- fect. There was also no consistent effect of time panning observed, with localization judgments for the broadband source becoming more biased towards the upper loud- speaker as ICTD increased, as opposed to the lower." [the upper speaker was always lagging behind the lower in this experiment.] in comparing the results with litovsky et al, it should be pointed out that while both were conducted under anechoic conditions, the stimuli used by wallis and lee were long noise snippets with 1s fade-ins and fade-outs rather than clicks, with no transient information at all (which seem designed to test the presence of summing localisation), so i guess they are not in direct contradiction. it just shows that the musical reality will be somewhere in between... > Certainly, in respect of producing phantom imagery in the vertical, > I've found this to be quite effective (though often slightly more > vague than in horizontal) which would explain why periphonic > ambisonics works at all - and this seems to be a related issue to the > precedence one i found that vbap/stereophonic vertical localisation is excellent on speaker positions (because it gets the spectral cues right), and unusable anywhere else. 3rd-order ambisonic vertical localisation seems uniformly so-so throughout the elevation range, which to me is preferrable... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net -------------- next part -------------- A non-text attachment was scrubbed... Name: 18040.pdf Type: application/pdf Size: 299653 bytes Desc: not available URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20151209/d9d9ec4c/attachment.pdf> _______________________________________________ Sursound mailing list [email protected] https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on. The University of Derby has a published policy regarding email and reserves the right to monitor email traffic. If you believe this was sent to you in error, please select unsubscribe. Unsubscribe and Security information contact: [email protected] For all FOI requests please contact: [email protected] All other Contacts are at http://www.derby.ac.uk/its/contacts/ _______________________________________________ Sursound mailing list [email protected] https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
