[Sursound] Dual hexagon using in-ceiling uppers and matching in-wall lowers
Hello All I am a long time lurker here, and have been interested in setting up an ambisonic listening room in my house for some time. I have finally got the courage to try, however the only room that I have available to use is multi-use and only of moderate size 20m^2 (3940*4750*2690mm) In order to be able to make the most of the space I have been thinking about using moderately high end in-wall and in ceiling speakers in an rectangular double-hexagon arrangement. My question here is two fold: 1 - Do you think that this is at all a good or interesting setup. Even with lots of work. I have a moderate undergraduate level of understanding of DSP and and have read almost everything that I can get my hands upon about both spherical harmonics and ambisonics and so feel able to write a custom decoder if I have to. 2 - If the answer to the first question is yes, do you think that the Noble-Fidelity L-85 LRCS (in ceiling) and L-82 (in wall lowers) would be an appropriate speaker for this purpose. If not what speaker would you recomend (if any). I am not attached to these speakers however I cannot afford much more than USD 300 for each speaker. -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131216/8a2b9c8d/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
[Sursound] status of ambisonia.com?
hi *! what's the status of ambisonia.com? it appears that while the site is distributing torrent metadata, nobody is actually seeding the files. i'd be willing to set up a permanent seeder if someone can put me in contact with the current site admin (at york, i believe?). best, jörn -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
[Sursound] Encoding a 7.1 audio DVD ?
Seeing as there is a dearth of 8 channel players - I was thinking I could just use a 7.1 DVD on a loop for an eight channel sound installation - as long as I can send a seperate audio signal to each of the 8 (the LF sends a full range signal too) there shouldnt be a problem. I encoded 5.1 DVD ages ago and I vaguely remember I needed several programs, one for encoding AC3, one for authoring etc etc - does anyone know programs would I need to encode a 7.1 DVD ? best, Gus -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131216/cc1ae32b/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] status of ambisonia.com?
--On 16 December 2013 16:14 +0100 Jörn Nettingsmeier netti...@stackingdwarves.net wrote: what's the status of ambisonia.com? it appears that while the site is distributing torrent metadata, nobody is actually seeding the files. I am currently seeding my files; the rest are available on my torrent server, but I need to fix the seeding which broke when I had to re-install the software - I guess this is a prompt to get on with it! There are very few downloads, so I'm not sure if the torrents from ambisonia.com are linking with my server correctly, or whether it's just that no one knows it's there; but a few of my files get downloaded somewhat regularly (Duruflé's Requiem and the excerpts from Purcell's King Arthur are the top choices). My files from Ambisonia (and John Leonard's, with permission) are also available from a very fast download site through links from my webpages at http://www.ambisonic.info/audio.html. Paul -- Paul Hodges ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] status of ambisonia.com?
Hi Jörn (and all) I'm in charge of Ambisonia (to some extent). Oliver Larkin is the contact at York. There's a seeder on the server, but it's not answering. I restarted the seeder, without success. I suspect that ports are being blocked from inside York; it happens from time to time... I'll send an email to Oliver. -- Marc Jörn Nettingsmeier netti...@stackingdwarves.net a écrit : hi *! what's the status of ambisonia.com? it appears that while the site is distributing torrent metadata, nobody is actually seeding the files. i'd be willing to set up a permanent seeder if someone can put me in contact with the current site admin (at york, i believe?). best, jörn ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Encoding a 7.1 audio DVD ?
Augustine Leudar wrote: Seeing as there is a dearth of 8 channel players - I was thinking I could just use a 7.1 DVD on a loop for an eight channel sound installation - as long as I can send a seperate audio signal to each of the 8 (the LF sends a full range signal too) there shouldnt be a problem. I encoded 5.1 DVD ages ago and I vaguely remember I needed several programs, one for encoding AC3, one for authoring etc etc - does anyone know programs would I need to encode a 7.1 DVD ? According to wikipedia DVD-Audio only does 5.1 - it could be wrong of course. The DVD-Video page claims 8ch PCM support is in the spec, but says it's not well supported by players. AFAIK in practice 7.1 is a bluray thing. ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] status of ambisonia.com?
Paul Hodges wrote: --On 16 December 2013 16:14 +0100 Jörn Nettingsmeier netti...@stackingdwarves.net wrote: what's the status of ambisonia.com? it appears that while the site is distributing torrent metadata, nobody is actually seeding the files. I agree that some seem unseeded and it was quite a while ago I tried - I did manage to get some and am still seeding these and some are being leeched occasionally. I am currently seeding my files; the rest are available on my torrent server, but I need to fix the seeding which broke when I had to re-install the software - I guess this is a prompt to get on with it! There are very few downloads, so I'm not sure if the torrents from ambisonia.com are linking with my server correctly, or whether it's just that no one knows it's there; but a few of my files get downloaded somewhat regularly (Duruflé's Requiem and the excerpts from Purcell's King Arthur are the top choices). My files from Ambisonia (and John Leonard's, with permission) are also available from a very fast download site through links from my webpages at http://www.ambisonic.info/audio.html. Thanks for that site, coincidently I was actually downloading some earlier today and found a dead link/mistake - Farmer - A Little Pretty Bonny Lass AMB DTS The AMB link points to the DTS dir and so doesn't work. https://ambisonic-files.s3.amazonaws.com/DTS/pwh-Farmer-ALittlePrettyBonnyLass.amb ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] status of ambisonia.com?
I am happy to host all the files for free here at MIT as direct downloads. If someone can pass along a directory to mirror, it takes 10 seconds to set up. Ben On Mon, Dec 16, 2013 at 11:18 AM, Andy Furniss adf.li...@gmail.com wrote: Paul Hodges wrote: --On 16 December 2013 16:14 +0100 Jörn Nettingsmeier netti...@stackingdwarves.net wrote: what's the status of ambisonia.com? it appears that while the site is distributing torrent metadata, nobody is actually seeding the files. I agree that some seem unseeded and it was quite a while ago I tried - I did manage to get some and am still seeding these and some are being leeched occasionally. I am currently seeding my files; the rest are available on my torrent server, but I need to fix the seeding which broke when I had to re-install the software - I guess this is a prompt to get on with it! There are very few downloads, so I'm not sure if the torrents from ambisonia.com are linking with my server correctly, or whether it's just that no one knows it's there; but a few of my files get downloaded somewhat regularly (Duruflé's Requiem and the excerpts from Purcell's King Arthur are the top choices). My files from Ambisonia (and John Leonard's, with permission) are also available from a very fast download site through links from my webpages at http://www.ambisonic.info/audio.html. Thanks for that site, coincidently I was actually downloading some earlier today and found a dead link/mistake - Farmer - A Little Pretty Bonny Lass AMB DTS The AMB link points to the DTS dir and so doesn't work. https://ambisonic-files.s3.amazonaws.com/DTS/pwh-Farmer- ALittlePrettyBonnyLass.amb ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131216/c6a743f4/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] status of ambisonia.com?
--On 16 December 2013 16:18 + Andy Furniss adf.li...@gmail.com wrote: Thanks for that site, coincidently I was actually downloading some earlier today and found a dead link/mistake - Farmer - A Little Pretty Bonny Lass AMB DTS The AMB link points to the DTS dir and so doesn't work. Thanks - that's now fixed. Paul -- Paul Hodges ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] status of ambisonia.com?
On 12/16/2013 04:48 PM, Marc Lavallée wrote: Hi Jörn (and all) I'm in charge of Ambisonia (to some extent). Oliver Larkin is the contact at York. There's a seeder on the server, but it's not answering. I restarted the seeder, without success. I suspect that ports are being blocked from inside York; it happens from time to time... I'll send an email to Oliver. thanks. like ben, i would be happy to host a direct download mirror if necessary, although torrent seeding would tie in to the existing system more easily. i used to seed permanently when etienne was still running the site, but neglected to reinstate the torrent server when the site moved to york. can you ask oliver how to obtain a list of all torrents, so that i can bring my seeder back up? -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Ambisonic depending Aural recognition,
Marc Lavallée wrote: Sun, 15 Dec 2013 23:40:01 +0100, Jörn Nettingsmeier netti...@stackingdwarves.net a écrit : The article is mentionned in the Linkedin profile of the co-author: http://www.linkedin.com/pub/kiarash-alimi/40/2b7/117 yes, and precisely nowhere else. also, the excerpt than aaron posts seems like gibberish to me... it is also only marginally related to the wikipedia article. No traces of the journal, the article or the author in either Worldcat or Google Scholar. Is it possible that the journal exists, but is not indexed? -- Marc Or maybe the article exists and is just bad? Direction perception in binaural hearing systems stems from minor Phase shifts of the dual received input material. Really If I would be professor and my students would write such a reduced (crap) nonsense... O:-) The auricle curvature, ethmoid bone and nasal septum shape the perceived sonar soundscape for each sample individual. So, forget the head and torso, which should be minor functor contributors, in this framework. (This was ironic.) Ethmoid bone and nasal septum shape sounds pretty cool! I will talk to my dentist about this stuff This paper's intention is to develop a framework of all possible functor structures for modeling different types of functor attributes in an in ear monitoring system in order to reproduce the lost ambisonic effect of various listeners using a rounded statistical morphology of 32 basic types of anatomic features. These are the 32 basic types. Now to the complex ones...:-) Best regards to all fellow crypto-scientists! Stefan ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Encoding a 7.1 audio DVD ?
Andy Furniss wrote: Augustine Leudar wrote: Seeing as there is a dearth of 8 channel players - I was thinking I could just use a 7.1 DVD on a loop for an eight channel sound installation - as long as I can send a seperate audio signal to each of the 8 (the LF sends a full range signal too) there shouldnt be a problem. I encoded 5.1 DVD ages ago and I vaguely remember I needed several programs, one for encoding AC3, one for authoring etc etc - does anyone know programs would I need to encode a 7.1 DVD ? According to wikipedia DVD-Audio only does 5.1 - it could be wrong of course. The DVD-Video page claims 8ch PCM support is in the spec, but says it's not well supported by players. Starts with the interface problems. Today you would use HDMI and USB for this. Not in any DVD specs... AFAIK in practice 7.1 is a bluray thing. Or you define a file format. (AAC and FLAC actually would support 7.1. This doesn't mean people are using such an option yet. Best, Stefan P.S.: BDs would support Dolby/DTS 7.1, which means discrete 7.1. Certainly not anything like Ambisonics, so you would need in any case a new format definition. ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Dual hexagon using in-ceiling uppers and matching in-wall lowers
Hello Alexis, A few things A) How were you planning on running your decoder? Write code from the ground up? Build your own hardware? If you're looking for something somewhat between 'off the shelf' and 'grow your own', you may like to have a look at the Ambisonic Toolkit package for SuperCollider. From the web page, SuperCollider is a programming language for real time audio synthesis and algorithmic composition. The new and the older pages are here: http://supercollider.github.io/ http://supercollider.sourceforge.net/ The page for the Ambisonic Toolkit is here: http://www.ambisonictoolkit.net B) On your decoder arrangement... I'd suggest you think about the bi-rectangle arrangement, which uses 8 loudspeakers. This can work well in a domestic situation. Four loudspeakers are placed in the horizontal plane (in a rectangle), and then two more on the ceiling and two on the floor. Imagine two planes bisecting each other: one horizontal and one vertical. The ATK has a wide variety of inbuilt decoders. This page lists them: http://doc.sccode.org/Classes/FoaDecoderMatrix.html For a bi-rectangle, you'd use the diametric decoder. For two hexagons, you'd use the periphonic decoder. The ATK also includes Near Field Compensation and Psychoacoustic Shelf Filtering, allowing you to implement classic, optimised decoders. Additionally, because SuperCollider is a programming language for audio synthesis and signal processing, you also get delay lines and multipliers (gain adjustment) to compensate for differences in loudspeaker distances. Hope this helps!! My best, Joseph Anderson j.ander...@ambisonictoolkit.net http://www.ambisonictoolkit.net On 16 Dec 2013, at 1:25 am, Alexis Shaw alexis.s...@gmail.com wrote: Hello All I am a long time lurker here, and have been interested in setting up an ambisonic listening room in my house for some time. I have finally got the courage to try, however the only room that I have available to use is multi-use and only of moderate size 20m^2 (3940*4750*2690mm) In order to be able to make the most of the space I have been thinking about using moderately high end in-wall and in ceiling speakers in an rectangular double-hexagon arrangement. My question here is two fold: 1 - Do you think that this is at all a good or interesting setup. Even with lots of work. I have a moderate undergraduate level of understanding of DSP and and have read almost everything that I can get my hands upon about both spherical harmonics and ambisonics and so feel able to write a custom decoder if I have to. 2 - If the answer to the first question is yes, do you think that the Noble-Fidelity L-85 LRCS (in ceiling) and L-82 (in wall lowers) would be an appropriate speaker for this purpose. If not what speaker would you recomend (if any). I am not attached to these speakers however I cannot afford much more than USD 300 for each speaker. -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131216/8a2b9c8d/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131216/2485a933/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Encoding a 7.1 audio DVD ?
Stefan Schreiber wrote: Andy Furniss wrote: According to wikipedia DVD-Audio only does 5.1 - it could be wrong of course. The DVD-Video page claims 8ch PCM support is in the spec, but says it's not well supported by players. Starts with the interface problems. Today you would use HDMI and USB for this. Not in any DVD specs... Yea, though it does hold out some hope that a blu-ray player that does dvds may support it and send 8xPCM over hdmi to a receiver. AFAIK in practice 7.1 is a bluray thing. Or you define a file format. (AAC and FLAC actually would support 7.1. This doesn't mean people are using such an option yet. I read the OPs post as meaning he wanted to use a consumer player - if a computer is an option then problem solved :-) P.S.: BDs would support Dolby/DTS 7.1, which means discrete 7.1. Certainly not anything like Ambisonics, so you would need in any case a new format definition. I think that PCM if possible would be the answer - I know there are open encoders for the core AC3/DTS 5.1 codecs, but not the TrueHD/MA that 7.1 blu-ray use, I guess certified commercial encoders are not cheap. Having had a look at the DTS spec (ETSI TS 102 114 v1.4.1) recently, though there are many possible channel layouts in there, it may be that blu-ray players only do 7.1 and in that case the .1 really is only for LFE - it is not stored/decoded as a full range channel. I don't know about TrueHD - the spec seems to be secret. Nothing to do with this thread and I am not saying that any players use it, but I did see the words Ambisonic and WXYZ in the spec, so there is some provision for carrying and flagging as special b-format in a DTS extension stream. ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Encoding a 7.1 audio DVD ?
If the bluray spec only supports up to 7.1, why are we seeing receivers with 11.2 outputs? Are those just matrixed channels with some reverb thrown in? I'll be thinking about this for my ambisonics setup. On Mon, Dec 16, 2013 at 1:14 PM, Andy Furniss adf.li...@gmail.com wrote: Stefan Schreiber wrote: Andy Furniss wrote: According to wikipedia DVD-Audio only does 5.1 - it could be wrong of course. The DVD-Video page claims 8ch PCM support is in the spec, but says it's not well supported by players. Starts with the interface problems. Today you would use HDMI and USB for this. Not in any DVD specs... Yea, though it does hold out some hope that a blu-ray player that does dvds may support it and send 8xPCM over hdmi to a receiver. AFAIK in practice 7.1 is a bluray thing. Or you define a file format. (AAC and FLAC actually would support 7.1. This doesn't mean people are using such an option yet. I read the OPs post as meaning he wanted to use a consumer player - if a computer is an option then problem solved :-) P.S.: BDs would support Dolby/DTS 7.1, which means discrete 7.1. Certainly not anything like Ambisonics, so you would need in any case a new format definition. I think that PCM if possible would be the answer - I know there are open encoders for the core AC3/DTS 5.1 codecs, but not the TrueHD/MA that 7.1 blu-ray use, I guess certified commercial encoders are not cheap. Having had a look at the DTS spec (ETSI TS 102 114 v1.4.1) recently, though there are many possible channel layouts in there, it may be that blu-ray players only do 7.1 and in that case the .1 really is only for LFE - it is not stored/decoded as a full range channel. I don't know about TrueHD - the spec seems to be secret. Nothing to do with this thread and I am not saying that any players use it, but I did see the words Ambisonic and WXYZ in the spec, so there is some provision for carrying and flagging as special b-format in a DTS extension stream. ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound -- Bearcat M. Şándor Feline Soul Systems LLC Voice: 872.CAT.SOUL (872.228.7685) Fax: 406.235.7070 Jabber/xmpp/gtalk/email: bear...@feline-soul.net MSN: bearcatsan...@hotmail.com Yahoo: bearcatsandor AIM: bearcatmsandor My public pgp key is included for verification of my identity -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131216/8d2e51d4/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Encoding a 7.1 audio DVD ?
Bearcat M. Şándor wrote: If the bluray spec only supports up to 7.1, why are we seeing receivers with 11.2 outputs? Are those just matrixed channels with some reverb thrown in? I'll be thinking about this for my ambisonics setup. When I said Having had a look at the DTS spec (ETSI TS 102 114 v1.4.1) recently, though there are many possible channel layouts in there, it may be that blu-ray players only do 7.1 and in that case the .1 really is only for LFE - it is not stored/decoded as a full range channel. I don't know about TrueHD - the spec seems to be secret. I was really meaning what every player/decoder should support as a minimum - to be blu-ray compatible. I think if the player passes on the whole DTS/Dolby stream to a more advanced decoder then it's quite possible that if present 11.2 real channels could be on the disk. Looking at wikipedia again I see it doesn't even say 7.1 is max for TrueHD and DTS-MA, it says 8ch so I guess I was wrong in saying 7.1 was max and what I wrote about LFE is wrong as long the channels are all flagged a full range. OP may still want to use PCM of course as there is the issue of encoders. I also realise I misread/skimmed the first line in this thread and took dearth of 8 channel players to mean there are plenty of 8ch players - strange ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
[Sursound] AmbiExplorer and TetraFile apps available now on Google Play
Hello, I would like to let you know that my previously announced apps, AmbiExplorer and TetraFile, have gone live on Google Play. They can be found here: https://play.google.com/store/apps/developer?id=Hector%20Centenohl=en Please let me know if you come across any technical problems or if you have any questions or suggestions. There's a short user guide in the preferences, accesible through the icon located on the right side of the action bar (top of the window). Best regards, Hector Centeno www.hcenteno.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Dual hexagon using in-ceiling uppers and matching in-wall lowers
Hi Joseph In terms of decoder I was intending to hack a hifi preamp with an 8 input-12output matrix 128k long fir filters. That is DFT the inputs, for each frequency in that fft multiply by a matrix, then do an IDFT on the output. Of course you do something a little more complicated in order to fix up latency problems. This, I think is the most general Ambisonic decoder that is possible at the moment. And if you play with the coefficients you can also do room correction, delay lines all in that framework. On Tuesday, December 17, 2013, Joseph Anderson wrote: Hello Alexis, A few things A) How were you planning on running your decoder? Write code from the ground up? Build your own hardware? If you're looking for something somewhat between 'off the shelf' and 'grow your own', you may like to have a look at the Ambisonic Toolkit package for SuperCollider. From the web page, SuperCollider is a programming language for real time audio synthesis and algorithmic composition. The new and the older pages are here: http://supercollider.github.io/ http://supercollider.sourceforge.net/ The page for the Ambisonic Toolkit is here: http://www.ambisonictoolkit.net B) On your decoder arrangement... I'd suggest you think about the bi-rectangle arrangement, which uses 8 loudspeakers. This can work well in a domestic situation. Four loudspeakers are placed in the horizontal plane (in a rectangle), and then two more on the ceiling and two on the floor. Imagine two planes bisecting each other: one horizontal and one vertical. The ATK has a wide variety of inbuilt decoders. This page lists them: http://doc.sccode.org/Classes/FoaDecoderMatrix.html For a bi-rectangle, you'd use the diametric decoder. For two hexagons, you'd use the periphonic decoder. The ATK also includes Near Field Compensation and Psychoacoustic Shelf Filtering, allowing you to implement classic, optimised decoders. Additionally, because SuperCollider is a programming language for audio synthesis and signal processing, you also get delay lines and multipliers (gain adjustment) to compensate for differences in loudspeaker distances. Hope this helps!! My best, Joseph Anderson j.ander...@ambisonictoolkit.net javascript:; http://www.ambisonictoolkit.net On 16 Dec 2013, at 1:25 am, Alexis Shaw alexis.s...@gmail.comjavascript:; wrote: Hello All I am a long time lurker here, and have been interested in setting up an ambisonic listening room in my house for some time. I have finally got the courage to try, however the only room that I have available to use is multi-use and only of moderate size 20m^2 (3940*4750*2690mm) In order to be able to make the most of the space I have been thinking about using moderately high end in-wall and in ceiling speakers in an rectangular double-hexagon arrangement. My question here is two fold: 1 - Do you think that this is at all a good or interesting setup. Even with lots of work. I have a moderate undergraduate level of understanding of DSP and and have read almost everything that I can get my hands upon about both spherical harmonics and ambisonics and so feel able to write a custom decoder if I have to. 2 - If the answer to the first question is yes, do you think that the Noble-Fidelity L-85 LRCS (in ceiling) and L-82 (in wall lowers) would be an appropriate speaker for this purpose. If not what speaker would you recomend (if any). I am not attached to these speakers however I cannot afford much more than USD 300 for each speaker. -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131216/8a2b9c8d/attachment.html ___ Sursound mailing list Sursound@music.vt.edu javascript:; https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131216/2485a933/attachment.html ___ Sursound mailing list Sursound@music.vt.edu javascript:; https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131217/f2349c8a/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Dual hexagon using in-ceiling uppers and matching in-wall lowers
Hello Alexis, Sounds like a fun project. What is the hardware you're hacking? My best, Joseph Anderson j.ander...@ambisonictoolkit.net http://www.ambisonictoolkit.net On 16 Dec 2013, at 3:13 pm, Alexis Shaw alexis.s...@gmail.com wrote: Hi Joseph In terms of decoder I was intending to hack a hifi preamp with an 8 input-12output matrix 128k long fir filters. That is DFT the inputs, for each frequency in that fft multiply by a matrix, then do an IDFT on the output. Of course you do something a little more complicated in order to fix up latency problems. This, I think is the most general Ambisonic decoder that is possible at the moment. And if you play with the coefficients you can also do room correction, delay lines all in that framework. On Tuesday, December 17, 2013, Joseph Anderson wrote: Hello Alexis, A few things A) How were you planning on running your decoder? Write code from the ground up? Build your own hardware? If you're looking for something somewhat between 'off the shelf' and 'grow your own', you may like to have a look at the Ambisonic Toolkit package for SuperCollider. From the web page, SuperCollider is a programming language for real time audio synthesis and algorithmic composition. The new and the older pages are here: http://supercollider.github.io/ http://supercollider.sourceforge.net/ The page for the Ambisonic Toolkit is here: http://www.ambisonictoolkit.net B) On your decoder arrangement... I'd suggest you think about the bi-rectangle arrangement, which uses 8 loudspeakers. This can work well in a domestic situation. Four loudspeakers are placed in the horizontal plane (in a rectangle), and then two more on the ceiling and two on the floor. Imagine two planes bisecting each other: one horizontal and one vertical. The ATK has a wide variety of inbuilt decoders. This page lists them: http://doc.sccode.org/Classes/FoaDecoderMatrix.html For a bi-rectangle, you'd use the diametric decoder. For two hexagons, you'd use the periphonic decoder. The ATK also includes Near Field Compensation and Psychoacoustic Shelf Filtering, allowing you to implement classic, optimised decoders. Additionally, because SuperCollider is a programming language for audio synthesis and signal processing, you also get delay lines and multipliers (gain adjustment) to compensate for differences in loudspeaker distances. Hope this helps!! My best, Joseph Anderson j.ander...@ambisonictoolkit.net javascript:; http://www.ambisonictoolkit.net On 16 Dec 2013, at 1:25 am, Alexis Shaw alexis.s...@gmail.comjavascript:; wrote: Hello All I am a long time lurker here, and have been interested in setting up an ambisonic listening room in my house for some time. I have finally got the courage to try, however the only room that I have available to use is multi-use and only of moderate size 20m^2 (3940*4750*2690mm) In order to be able to make the most of the space I have been thinking about using moderately high end in-wall and in ceiling speakers in an rectangular double-hexagon arrangement. My question here is two fold: 1 - Do you think that this is at all a good or interesting setup. Even with lots of work. I have a moderate undergraduate level of understanding of DSP and and have read almost everything that I can get my hands upon about both spherical harmonics and ambisonics and so feel able to write a custom decoder if I have to. 2 - If the answer to the first question is yes, do you think that the Noble-Fidelity L-85 LRCS (in ceiling) and L-82 (in wall lowers) would be an appropriate speaker for this purpose. If not what speaker would you recomend (if any). I am not attached to these speakers however I cannot afford much more than USD 300 for each speaker. -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131216/8a2b9c8d/attachment.html ___ Sursound mailing list Sursound@music.vt.edu javascript:; https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131216/2485a933/attachment.html ___ Sursound mailing list Sursound@music.vt.edu javascript:; https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131217/f2349c8a/attachment.html
Re: [Sursound] Dual hexagon using in-ceiling uppers and matching in-wall lowers
On Tue, Dec 17, 2013 at 10:13:15AM +1100, Alexis Shaw wrote: In terms of decoder I was intending to hack a hifi preamp with an 8 input-12output matrix 128k long fir filters. That is DFT the inputs, for each frequency in that fft multiply by a matrix, then do an IDFT on the output. 1. That's giant overkill, completely useless. Whatever you need as filtering in a decoder can be done easily with much shorter impulse response. Or even with some simple IIR filters. 2. The method you propose (DFT, matrix, IDFT) is wrong, you'd need linear convolution which is not the same thing. Ciao, -- FA A world of exhaustive, reliable metadata would be an utopia. It's also a pipe-dream, founded on self-delusion, nerd hubris and hysterically inflated market opportunities. (Cory Doctorow) ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Dual hexagon using in-ceiling uppers and matching in-wall lowers
On Tuesday, December 17, 2013, Fons Adriaensen wrote: On Tue, Dec 17, 2013 at 10:13:15AM +1100, Alexis Shaw wrote: In terms of decoder I was intending to hack a hifi preamp with an 8 input-12output matrix 128k long fir filters. That is DFT the inputs, for each frequency in that fft multiply by a matrix, then do an IDFT on the output. 1. That's giant overkill, completely useless. Whatever you need as filtering in a decoder can be done easily with much shorter impulse response. Or even with some simple IIR filters. It is overkill for anything except room correction where you often need 1/2 second of filtering At 386khz that leads to a 128k fir filter 2. The method you propose (DFT, matrix, IDFT) is wrong, you'd need linear convolution which is not the same thing. No you are wrong here, convolusion in. The time domain is equivelent to multiplication in the Fourier domain. That is simple sampling theory. Look up the overlap and add method of fir filter implementation Ciao, -- FA A world of exhaustive, reliable metadata would be an utopia. It's also a pipe-dream, founded on self-delusion, nerd hubris and hysterically inflated market opportunities. (Cory Doctorow) ___ Sursound mailing list Sursound@music.vt.edu javascript:; https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131217/326bfd22/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Dual hexagon using in-ceiling uppers and matching in-wall lowers
Hi Joseph. I am thinking of hacking the emotiva UMC-200, if I use the secondary zone DACs I should be able to get some reasonable quality out of it. Regards Alexis Shaw On Tuesday, December 17, 2013, Joseph Anderson wrote: Hello Alexis, Sounds like a fun project. What is the hardware you're hacking? My best, Joseph Anderson j.ander...@ambisonictoolkit.net javascript:; http://www.ambisonictoolkit.net On 16 Dec 2013, at 3:13 pm, Alexis Shaw alexis.s...@gmail.comjavascript:; wrote: Hi Joseph In terms of decoder I was intending to hack a hifi preamp with an 8 input-12output matrix 128k long fir filters. That is DFT the inputs, for each frequency in that fft multiply by a matrix, then do an IDFT on the output. Of course you do something a little more complicated in order to fix up latency problems. This, I think is the most general Ambisonic decoder that is possible at the moment. And if you play with the coefficients you can also do room correction, delay lines all in that framework. On Tuesday, December 17, 2013, Joseph Anderson wrote: Hello Alexis, A few things A) How were you planning on running your decoder? Write code from the ground up? Build your own hardware? If you're looking for something somewhat between 'off the shelf' and 'grow your own', you may like to have a look at the Ambisonic Toolkit package for SuperCollider. From the web page, SuperCollider is a programming language for real time audio synthesis and algorithmic composition. The new and the older pages are here: http://supercollider.github.io/ http://supercollider.sourceforge.net/ The page for the Ambisonic Toolkit is here: http://www.ambisonictoolkit.net B) On your decoder arrangement... I'd suggest you think about the bi-rectangle arrangement, which uses 8 loudspeakers. This can work well in a domestic situation. Four loudspeakers are placed in the horizontal plane (in a rectangle), and then two more on the ceiling and two on the floor. Imagine two planes bisecting each other: one horizontal and one vertical. The ATK has a wide variety of inbuilt decoders. This page lists them: http://doc.sccode.org/Classes/FoaDecoderMatrix.html For a bi-rectangle, you'd use the diametric decoder. For two hexagons, you'd use the periphonic decoder. The ATK also includes Near Field Compensation and Psychoacoustic Shelf Filtering, allowing you to implement classic, optimised decoders. Additionally, because SuperCollider is a programming language for audio synthesis and signal processing, you also get delay lines and multipliers (gain adjustment) to compensate for differences in loudspeaker distances. Hope this helps!! My best, Joseph Anderson j.ander...@ambisonictoolkit.net javascript:; javascript:; http://www.ambisonictoolkit.net On 16 Dec 2013, at 1:25 am, Alexis Shaw alexis.s...@gmail.comjavascript:; javascript:; wrote: Hello All I am a long time lurker here, and have been interested in setting up an ambisonic listening room in my house for some time. I have finally got the courage to try, however the only room that I have available to use is multi-use and only of moderate size 20m^2 (3940*4750*2690mm) In order to be able to make the most of the space I have been thinking about using moderately high end in-wall and in ceiling speakers in an rectangular double-hexagon arrangement. My question here is two fold: 1 - Do you think that this is at all a good or interesting setup. Even with lots of work. I have a moderate undergraduate level of understanding of DSP and and have read almost everything that I can get my hands upon about both spherical harmonics and ambisonics and so feel able to write a custom decoder if I have to. 2 - If the answer to the first question is yes, do you think that the Noble-Fidelity L-85 LRCS (in ceiling) and L-82 (in wall lowers) would be an appropriate speaker for this purpose. If not what speaker would you recomend (if any). I am not attached to these speakers however I cannot afford much more than USD 300 for each speaker. -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131216/8a2b9c8d/attachment.html ___ Sursound mailing list Sursound@music.vt.edu javascript:; javascript:; https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments
Re: [Sursound] Dual hexagon using in-ceiling uppers and matching in-wall lowers
On Tue, Dec 17, 2013 at 10:53:23AM +1100, Alexis Shaw wrote: 1. That's giant overkill, completely useless. Whatever you need as filtering in a decoder can be done easily with much shorter impulse response. Or even with some simple IIR filters. It is overkill for anything except room correction where you often need 1/2 second of filtering At 386khz that leads to a 128k fir filter * 386 kHz ?? Even 192 is completely useless. * Half a second of room correction would be useful only at very low frequencies (unless you want to correct your bathroom). And if and when it is necesssary, that part of the frequency range can be processed at a much lower sample rate and require only a short filter. * And then, room correction would be done on the speaker signals, not on the complete matrix. The latter *is* possible of course, and would be ideal, *iff* you can derive the filters. Which would require measuring the room response in higher order Ambisonic format, not on option unless you have a EigenMike, and even then dubious. 2. The method you propose (DFT, matrix, IDFT) is wrong, you'd need linear convolution which is not the same thing. No you are wrong here, convolusion in. The time domain is equivelent to multiplication in the Fourier domain. That is simple sampling theory. Look up the overlap and add method of fir filter implementation You don't have to tell me that (as the author of zita-convolver). But DFT, multiply, IDFT without overlap (which is what the OP described) won't do it. Ciao, -- FA A world of exhaustive, reliable metadata would be an utopia. It's also a pipe-dream, founded on self-delusion, nerd hubris and hysterically inflated market opportunities. (Cory Doctorow) ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Dual hexagon using in-ceiling uppers and matching in-wall lowers
On Tuesday, December 17, 2013, Fons Adriaensen wrote: On Tue, Dec 17, 2013 at 10:53:23AM +1100, Alexis Shaw wrote: 1. That's giant overkill, completely useless. Whatever you need as filtering in a decoder can be done easily with much shorter impulse response. Or even with some simple IIR filters. It is overkill for anything except room correction where you often need 1/2 second of filtering At 386khz that leads to a 128k fir filter * 386 kHz ?? Even 192 is completely useless. * Half a second of room correction would be useful only at very low frequencies (unless you want to correct your bathroom). And if and when it is necesssary, that part of the frequency range can be processed at a much lower sample rate and require only a short filter. * And then, room correction would be done on the speaker signals, not on the complete matrix. The latter *is* possible of course, and would be ideal, *iff* you can derive the filters. Which would require measuring the room response in higher order Ambisonic format, not on option unless you have a EigenMike, and even then dubious. My other project is making an eigenmike type microphone using 1000 mems microphones I am intending to do that 2. The method you propose (DFT, matrix, IDFT) is wrong, you'd need linear convolution which is not the same thing. No you are wrong here, convolusion in. The time domain is equivelent to multiplication in the Fourier domain. That is simple sampling theory. Look up the overlap and add method of fir filter implementation You don't have to tell me that (as the author of zita-convolver). But DFT, multiply, IDFT without overlap (which is what the OP described) won't do it. Btw I am the op. Ciao, -- FA A world of exhaustive, reliable metadata would be an utopia. It's also a pipe-dream, founded on self-delusion, nerd hubris and hysterically inflated market opportunities. (Cory Doctorow) ___ Sursound mailing list Sursound@music.vt.edu javascript:; https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20131217/b800bf3d/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
