Re: [Sursound] Nevaton microphones
t; the same array will start aliasing, i.e. when the speakers are separated > by half a wavelength. > > Above that frequency the two systems diverge. WFS will produce aliased > images, and for AMB primary sources will start to be projected onto the > circle of speakers. I wonder if some 'halfway' solution could be found > in this frequency range, one that would combine but mitigate the defects > of the two systems... > > 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 > -- As of 1st October 2012, I have retired from the University, so this disclaimer is redundant These are my own views and may or may not be shared by my employer Dave Malham Ex-Music Research Centre Department of Music The University of York Heslington York YO10 5DD UK 'Ambisonics - Component Imaging for Audio' -- next part -- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20130619/405df757/attachment.html> ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Eigenmike
Like I said - go away and all sorts of interesting stuff comes up. On 11 June 2013 23:02, Fons Adriaensen wrote: > Part of the problem may be that even while the Eigenmic capsules are of > very high quality, the remaining random differences in sensitivity > and frequency response are still too large to allow accurate higher > order processing without individual calibration. I have wondered if, at least post recording, something could be done by looking at the end of the reverb tail which, at least in some environments, would be pretty well directionally homogeneous. Differences between capsule outputs should then be due to sensitivity/frequency response rather than direction. > And until someone > finds a better method than renting an anechoic room for half a day, > such calibration is an expensive exercise. > > There is a method that can be used if you have an open area, no wind, and a nice warm dry climate and that's to sit your speaker in a hole in the ground pointing up and mount the mike two or three meters above. Do it properly and its essentially in a reflection free environment. Vastly cheaper than an anechoic room but, of course, totally at the mercy of the weather, so not good for a production environment though one of the mic manufacturers did use it for a while - can't remember which one but it was in an AES paper a good few years ago - which is where I got the idea. Dave -- As of 1st October 2012, I have retired from the University, so this disclaimer is redundant These are my own views and may or may not be shared by my employer Dave Malham Ex-Music Research Centre Department of Music The University of York Heslington York YO10 5DD UK 'Ambisonics - Component Imaging for Audio' -- next part -- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20130619/5b97ecd7/attachment.html> ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Subsumption Architecture meets Ambisonics?
On 6 June 2013 12:35, Peter Lennox wrote: > Just a quick one (I have to get back to the altogether-more-important > paperwork and meetings!) > > I regularly have student record, or fabricate, or combinations, of 'walk > through/ride through/other journey, sometimes using SF ic sometimes > binaural, sometimes mixtures of spot mic inserted into sound field and so > on. > Me too - and I agree with the comments. I think the reason is perceptual as you *know* you aren't moving so that means the perceptual model matching that we do comes up with the answer "the sounds are moving". Some other cues need to go in - visual ? tactile? air movements? Dave > > One thing that is clear is that the SF mics are very susceptible to wind > noise, handling noise, vibration (bone conduction of the walker, even > trolleys with suspension and pneumatic tyres on a smooth surface). > > But another is that it is very, very difficult to get a journey recorded > in such a way that the eventual listener's perception is of gliding through > a landscape. Instead, it usually feels as though key elements of the > landscape are smoothly panned pas the stationary listening position. There > has to be something in the soundscape that perceptually 'explains' that the > listener is supposed to understand that they are moving through the > environment rather than that elements of the environment are moving pas the > perceiver, if you see what I mean > > ON a similar note, I had arranged, but the arrnagment fell through, to > dangle an SF mic below a hot air balloon as we fly over the landscape. IN > reasonably clement conditions, with a smoothly constant windspeed (no > turbulence) the effect ought to be of moving, and there should be no wind > noise. Since I am given to understand that sounds from the ground reach the > balloon often without accompanied early reflections, things tend to sound > much closer. > I'd still like to try it, but would be interested to see (hear) whether > one gets an impression of moving over the landscape, on listening. > > Cheers, back to the meeting... > Dr. Peter Lennox > > School of Technology, > Faculty of Arts, Design and Technology > University of Derby, UK > e: p.len...@derby.ac.uk > t: 01332 593155 > > > -Original Message- > From: sursound-boun...@music.vt.edu [mailto:sursound-boun...@music.vt.edu] > On Behalf Of Eric Carmichel > Sent: 05 June 2013 21:50 > To: sursound@music.vt.edu > Subject: [Sursound] Subsumption Architecture meets Ambisonics? > > Howdy (again), > Available Ambisonic recordings are mainly of spacially-separated, > stationary objects (e.g. musical instruments) or of a dominant moving > object (aeroplanes, helicopters). I was wondering whether anybody has > attached an Ambisonic microphone to a mobile device and then recorded the > surroundings as though the mic were the moving object. If so, are such > recordings available? Attaching an Ambisonic mic to one of Rodney Brook's > robots and then sending it through a shopping mall could create interesting > effects. Would the end listener get a sense of motion (thus inducing > dizziness) or feel he/she is following a path that seems "appropriate" > based on the echo-location of walls, people, etc. Anybody game to try? > Eric C. > -- next part -- > An HTML attachment was scrubbed... > URL: < > https://mail.music.vt.edu/mailman/private/sursound/attachments/20130605/b8a1e4c3/attachment.html > > > ___ > Sursound mailing list > Sursound@music.vt.edu > https://mail.music.vt.edu/mailman/listinfo/sursound > > _ > The University of Derby has a published policy regarding email and > reserves the right to monitor email traffic. If you believe this email was > sent to you in error, please notify the sender and delete this email. > Please direct any concerns to info...@derby.ac.uk. > ___ > Sursound mailing list > Sursound@music.vt.edu > https://mail.music.vt.edu/mailman/listinfo/sursound > -- As of 1st October 2012, I have retired from the University, so this disclaimer is redundant These are my own views and may or may not be shared by my employer Dave Malham Ex-Music Research Centre Department of Music The University of York Heslington York YO10 5DD UK 'Ambisonics - Component Imaging for Audio' -- next part -- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20130619/6aa75a8f/attachment.html> ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Subsumption Architecture meets Ambisonics?
The new Rycote suspensions, which are not _too_ expensive, are very good Dave On 6 June 2013 23:22, Eric Carmichel wrote: > Hi Michael, > Thanks--I'll shout if need be. > RE earthquake detectors: I suppose a good shock mount with seismic > isolation would help. Maybe filtering infrasonic frequencies would help > some, too, but low vibrations at mic could affect the audible frequencies? > That is, mechanically modulate frequencies (FM distortion) or cause basic > overload at preamp front end and ahead of active filtering. Maintaining a > favorable SNR can be a challenge with Ambisonic recording because > compression is avoided. Everday sounds can be LOUD when they're close to > our heads. Ever measure the SPL of a newspaper being rattled while at a > distance of 1 foot? I'll bet it's *louder* than we might guess. RE loudness > recruitment (a topic on its own): Without compression, everyday sounds can > be quite alarming to new hearing aid users. For those of us who can accept > a wide dynamic range, we take much of this for granted. > Walkabout files: The very best, or at least convincing, binaural file I > have listened to was made with in-the-ear 1/8-inch mics. Don't remember > where I got these, but they came with a silicon rubber *ring* that fit well > within concha, placing the mic roughly at the external auditory meatus and > without obstructions. These purportedly had self-noise of 10 dBA -- quite > low for a weenie-sized electrets (and possibly an exaggeration). Their tiny > cables looked disproportionate to their two XLR ends, which held some > active components (a FET or something -- never looked). Anyway, recordings > made with these mics were truly eery to listen to--I would dodge things > that appeared to be at my feet, and the sound of a squeaky would floor was > ghostly. At the time of recording, all I did was meander through the house, > pet my cat, bounce a tennis ball, and record a few everyday events. This > particular binaural recording took my whole body into account -- a full body > transfer function -- and probably wouldn't have been so effective for any > other listener. Don't know whether I can create the same "eery" experience > in near (or sound) field and with a cubic arrangement of speakers. Could be > fun... > Thanks, as always, for insights and help. > Best, > Eric C. > > > > > From: Michael Chapman > To: Eric Carmichel ; Surround Sound discussion group < > sursound@music.vt.edu> > Sent: Thursday, June 6, 2013 2:02 PM > Subject: Re: [Sursound] Subsumption Architecture meets Ambisonics? > > > > > > Seem to recall seeing various binaural 'walking about' files ... but don't > ask me where ... > > The problem seems to be (and ask someone else) that any omni mic (and a > tetrahedral is -amongst other things- an omni) is a very sensitive > 'earthquake detector' > > As for files: For my sins I run a server in Geneva. > One off downloads are not a problem. > Uploads mean turning off (or perhaps 'down') the security* for a while. > So if you are really stuck, shout. > > Michael > > > *I physically installed it. > Before it had a URL (i.e. DNS), just an IP address, during the > installation when I was putting it in place it started being attacked ... > aint the Internet wonderful ;-))>> > -- next part -- > An HTML attachment was scrubbed... > URL: < > https://mail.music.vt.edu/mailman/private/sursound/attachments/20130606/a59afd53/attachment.html > > > ___ > Sursound mailing list > Sursound@music.vt.edu > https://mail.music.vt.edu/mailman/listinfo/sursound > -- As of 1st October 2012, I have retired from the University, so this disclaimer is redundant These are my own views and may or may not be shared by my employer Dave Malham Ex-Music Research Centre Department of Music The University of York Heslington York YO10 5DD UK 'Ambisonics - Component Imaging for Audio' -- next part -- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20130619/c177979a/attachment.html> ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] mixed order decoding (was: HOA Soundscenes)
On 9 June 2013 01:15, Sampo Syreeni wrote: > On 2013-06-08, Fons Adriaensen wrote: > > mixed order recordings will often be played over a huge number of >>> loudspeakers. the "worst" setup i've heard my stuff on was 40. great for >>> spot localisation, but your first-order reverb will be a phasy mess [...] >>> >> >> [...] Still having at least the early part of the reverb in 'true' high >> order improves things, but it's not so easy to synthesise convincing early >> reflection matching a given space. >> > > This is off to my usual, messy tangent, but... It once came as a big > surprise to me at least that the separate orders cannot be optimally > decoded by a static, shared decoder. It might have been you who pointed > this out to me, or perhaps Angelo or Filippo, my memory fails me. In any > case, that fact has been bugging me for the longest time, because it's just > such an inelegant feature of the general framework. A blemish. > > > I think that was me - story goes Ambrose Field and I were invited to give presentations at a session at Ircam in the late nineties. On the train there (possibly when in the Channel Tunnel, but not completely sure) I was doing some back of the envelope calculations (literally, no laptop/pda/smartphone then) and became increasingly more worried when I couldn't find any way of doing mixed order decoding. Given the fact that this was when I first started thinking about eventually became FuMa a couple of years later, this made for a less than happy journey. Of course, Paris soon cured that! The only way I could (and can) see to work round it (I don't like active decoders as there are always artefacts for at least some material)) is to have either full separate B format streams for the first order only components or to have at least separate W channels for the first order only B format set and the set that also has higher order components. Messy, error prone and not goodbut at least it can work. Dave > Sursound mailing list > Sursound@music.vt.edu > https://mail.music.vt.edu/**mailman/listinfo/sursound<https://mail.music.vt.edu/mailman/listinfo/sursound> > -- As of 1st October 2012, I have retired from the University, so this disclaimer is redundant These are my own views and may or may not be shared by my employer Dave Malham Ex-Music Research Centre Department of Music The University of York Heslington York YO10 5DD UK 'Ambisonics - Component Imaging for Audio' -- next part -- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20130619/6d1b764d/attachment.html> ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
