Re: [Sursound] 3D Array

[Jörn Nettingsmeier]

On 09/28/2012 05:01 AM, Sampo Syreeni wrote:


This sort of a thing makes it easy for the composer, which is just
wicked cool. That makes people provide more content. But at the same
time, it doesn't help the developer who wants to incorporate ambisonic
into hir software. There, I'm pretty sure what would be needed would be
an all-encompassing ANSI C conformant library.

Does anybody around here have any ideas of how to produce something like
that? Not as an alternative to the ATK, but as a parallel implementation
aimed at the lower level implementers? Perhaps with some extra API's for
low level use? Preferably even sharing code, where possible?


off the top of my hat, there is a toolkit available from t-labs at tu 
berlin, and iem graz has higher-order code for pd.



--
Jörn Nettingsmeier
Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487

Meister für Veranstaltungstechnik (Bühne/Studio)
Tonmeister VDT

http://stackingdwarves.net

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Re: [Sursound] 3D Array

[Sampo Syreeni]

On 2012-09-27, Joseph Anderson wrote:

Our goal is to have a complete system conveniently encompassing the 
tasks of encoding, processing, and finally decoding for artists and 
composers interested in working with Ambisonics. [...]


I see that you're working with Max/MSP at the moment. Our currently 
release of the ATK is as a SuperCollider library.


This sort of a thing makes it easy for the composer, which is just 
wicked cool. That makes people provide more content. But at the same 
time, it doesn't help the developer who wants to incorporate ambisonic 
into hir software. There, I'm pretty sure what would be needed would be 
an all-encompassing ANSI C conformant library.


Does anybody around here have any ideas of how to produce something like 
that? Not as an alternative to the ATK, but as a parallel implementation 
aimed at the lower level implementers? Perhaps with some extra API's for 
low level use? Preferably even sharing code, where possible?


At the moment we haven't implemented HOA features, but there are plans 
to begin with this aspect from January.


There in particular I'd ask for help from various weird circuits, 
because arbitrary order of HOA calls for some pretty weird code. It's 
numerically funky even at fourth order, not to mention at the orders 
which approach a hundred, which is what the highest WFS folks seem to do 
nowadays with their simpler, linear arrays. I'm pretty sure the two 
frameworks could be folded into a single library, just as they 
theoretically fold into the same holophonic framework. So, does 
everybody work together for the common goal, here? :)

--
Sampo Syreeni, aka decoy - de...@iki.fi, http://decoy.iki.fi/front
+358-50-5756111, 025E D175 ABE5 027C 9494 EEB0 E090 8BA9 0509 85C2
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Re: [Sursound] Demo / test piece

[Aaron Heller]

Very good idea.  OK with me.

Aaron (hel...@ai.sri.com)
Menlo Park, CA  US

On Thu, Sep 27, 2012 at 3:43 AM, Michael Chapman  wrote:
>
> Earlier today, I referred to a slow pan of a symphonic piece.
>
> Perhaps it would be of interest to others :
> -as a demo of ambisonic panning (yawing)
> -as a 'test' of how smooth it reproduces on rigs.
>
> Would be happy to post it on Ambisonia, if
> -any interest
> -Aaron ia agreeable(*) and obviously under his
> original copyright.
>
> Michael
>
> *It is a derivative of
> 
> "Johannes Brahms: Sym No. 1 in c minor, Op. 68, 4th mvt."
> Easy enough to 'cook' at home, but it might help newbies ...
>
>
> ___
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> https://mail.music.vt.edu/mailman/listinfo/sursound
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Re: [Sursound] Plane waves from natural sources...

[Sampo Syreeni]

On 2012-09-24, Fons Adriaensen wrote:

For a line of uncorrelated sources we have to add powers. Imagine the 
line source as the x-axis, with the origin being the point nearest to 
you. Let your distance be 'd'. Then the distance to a point 'x' on the 
line is sqrt(d^2 + x^d). The total power at distance 'd' is the 
integral from -inf to +inf of 1/(d^2 + x^2), which is 2 * pi / d, i.e. 
proportional to 1 / d, hence -3dB for each doubling of the distance.


This by the way is precisely the same kind of analysis -- in substance 
if not in details -- which is used to justify energy decoding over wide 
ambisonic rigs, by Gerzon, and a square root scaling in summation 
weights in DSP systems as a function of channels summed together, so as 
to minimize expected headroom. The statistical assumption it hinges on 
is that the source signals are independent average gaussian white noise. 
That assumption frequency-wise breaks down for highways especially at 
the lower end, a fact which environmental noise models already have to 
take note of.

--
Sampo Syreeni, aka decoy - de...@iki.fi, http://decoy.iki.fi/front
+358-50-5756111, 025E D175 ABE5 027C 9494 EEB0 E090 8BA9 0509 85C2
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Re: [Sursound] 3D Array

[Steven J. Dale]

Wow, thanks for the great info all... will review all of these and post
back soon...




  ┈┈
  Steven J. Dale  :  projects <http://www.cstreams.com/projects>
@lifeinchords <http://www.twitter.com/lifeinchords>
sounds<http://soundcloud.com/lifeinchords>
  Sound Artist : Designer :  Web Architect








On Thu, Sep 27, 2012 at 8:33 AM, Augustine Leudar  wrote:

> oohh - another thing I forgot to mention - Jack audio server is brilliant
> for routing different things into different things - so if you did want to
> use logic you could and just output channels via Jack into Max . It also
> works on Linux, OSX or windows - I would also highly recommend reaper
> though if your not overly used to logic 
>
>
> On 27 September 2012 11:26, Joseph Anderson  >wrote:
>
> > Hello Steven,
> >
> > I'm going to throw in a quick plug for the Ambisonic Toolkit (ATK):
> >
> > http://ambisonictoolkit.net/
> >
> > Our goal is to have a complete system conveniently encompassing the tasks
> > of encoding, processing, and finally decoding for artists and composers
> > interested in working with Ambisonics. Regarding the notion of
> > completeness, the idea is, if something can be done with Ambisonics, we'd
> > like to make that possible with the ATK.
> >
> > Here's an intro page to the documentation (55 pages!), to give you an
> > overview:
> >
> > http://www.ambisonictoolkit.net/Help/Guides/Intro-to-the-ATK.html
> >
> >
> > And the library browser page:
> >
> >
> >
> http://www.ambisonictoolkit.net/Help/Browse.html#Libraries%3EAmbisonic%20Toolkit
> >
> >
> >
> > I see that you're working with Max/MSP at the moment. Our currently
> > release of the ATK is as a SuperCollider library. We've gone w/
> > SuperCollider as it gives a tremendous amount of flexibility--as does
> > Ambisonics, so we feel they're a good match.
> >
> > At the moment we haven't implemented HOA features, but there are plans to
> > begin with this aspect from January.
> >
> >
> >
> > My kind regards,
> >
> > ~~
> > Joseph Anderson
> >
> > Artist: http://joseph-anderson.org
> > Ambisonic Toolkit:  http://ambisonictoolkit.net
> >
> >
> >
> >
> > On 27 Sep 2012, at 12:45 am, Steven J. Dale wrote:
> >
> > > Hi all,
> > >
> > > I'm new to Ambisonics, but very interested in writing music/sound for
> an
> > > installation in this format.
> > > I'm getting bits and pieces from many sources, but having a hard time
> > > piecing it all together.. I am wondering what's the most economical,
> DIY
> > > way of creating my own array of speakers to get started, and these
> > specific
> > > questions
> > >
> > > - Are identical speakers needed for each speaker of the array, or can I
> > DIY
> > > it buy mixing and matching speakers from old hi/fi and found systems?
> > > - I was reading that the exact layout of an HOA is not so important,
> > > there's tolerance for different configs, unlike traditional 5.1 channel
> > > based systems which have specific locations that they should live in..
> if
> > > so, what is the determining factor for accurate localization? If I rig
> up
> > > my studio with one config, will it translate to a much larger space by
> > > scaling up ? (assuming enough power in the loudspeakers?)
> > > - What are ways of writing original music for this format? I use Logic
> > and
> > > Max... does this format need specific compatible syths/instrument with
> > > multiple out, or is the source irrelevant and it's all in the host
> > routing?
> > > - What's the easiest way of using my existing stereo samples/recordings
> > to
> > > convert them for use and reproduction ? Is this even possible? If I
> > > convert, will I then have to manually 'map' movement across the field?
> > >
> > > So many questions! If anyone has time, would love to chat with you
> about
> > > all of this  much appreciated.
> > >
> > > Sounds like a ripe opportunity to create a set of tutorials, podcasts,
> > > screencasts of how to get started (if there aren't already)
> > >
> > > Thanks!
> > >
> > >
> > >  ┈┈
> > >  Steven J. Dale  :  projects <http://www.cstreams.com/projects>
> > > @lifein

Re: [Sursound] DIY MADI to ADAT converter - RE: "Digital Amplifiers" (Multichannel Amps with ADAT input)

[Dave Malham]

Thanks for pointing this out! What might be interesting to think about w.r.t. RPi's (given the lack 
of a full TDM type interface) is the possibility of modifying this to an Ethernet to ADAT interface. 
I haven't studied the design in detail but it might well be possible, given the fact that the MADI 
physical layer is done via an Ethernet chip, to change the function of the fpga to use an Ethernet 
stack to ADAT protocol, rather than MADI.


Incidentally, someone once published the ADAT protocol after some reverse engineering (ah-hm) but 
there is much more info at


www.wavefrontsemi.com/UserFiles/File/AL_Info/AL31/AppNotes/WavefrontAN3101-10 S-Mux Receiver for 
ADAT Optical Protocol.pdf


and also at

https://ackspace.nl/wiki/ADAT_project

Dave



On 27/09/2012 13:48, Bo-Erik Sandholm wrote:

I found this when I was trying to find a low cost way to interface a RPi to a 
MOTU traveler MK3 to create a compact portable DAW.
So far I have not found lowcost ARM board with firewire interface or 
possibility to plugin firewire, pcmcia, pcie, +

http:// http://madi.webklik.nl/page/madi  MADI to ADAT DIY  project.

I belive it might be of interest.

Bo-Erik


---

On a related note: anyone knows an alternative for the RME ADI-648 (MADI <-> 
ADAT bridge) ?

A few days ago two more failed at the CdS, these are the 5th and 6th. In all 
cases it seems to be the power supply. And it's not excessive temperature as we 
were thinking before - these two were operating in a conditioned environment 
and never have been 'too hot'.

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)

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 These are my own views and may or may not be shared by my employer
/*/
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/* Music Research Centre */
/* Department of Music"http://music.york.ac.uk/";   */
/* The University of York  Phone 01904 322448*/
/* Heslington  Fax   01904 322450*/
/* York YO10 5DD */
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[Sursound] DIY MADI to ADAT converter - RE: "Digital Amplifiers" (Multichannel Amps with ADAT input)

[Bo-Erik Sandholm]

I found this when I was trying to find a low cost way to interface a RPi to a 
MOTU traveler MK3 to create a compact portable DAW.
So far I have not found lowcost ARM board with firewire interface or 
possibility to plugin firewire, pcmcia, pcie, +

http:// http://madi.webklik.nl/page/madi  MADI to ADAT DIY  project.

I belive it might be of interest.

Bo-Erik


---

On a related note: anyone knows an alternative for the RME ADI-648 (MADI <-> 
ADAT bridge) ?

A few days ago two more failed at the CdS, these are the 5th and 6th. In all 
cases it seems to be the power supply. And it's not excessive temperature as we 
were thinking before - these two were operating in a conditioned environment 
and never have been 'too hot'. 

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)

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Re: [Sursound] 3D Array

[Augustine Leudar]

oohh - another thing I forgot to mention - Jack audio server is brilliant
for routing different things into different things - so if you did want to
use logic you could and just output channels via Jack into Max . It also
works on Linux, OSX or windows - I would also highly recommend reaper
though if your not overly used to logic 


On 27 September 2012 11:26, Joseph Anderson wrote:

> Hello Steven,
>
> I'm going to throw in a quick plug for the Ambisonic Toolkit (ATK):
>
> http://ambisonictoolkit.net/
>
> Our goal is to have a complete system conveniently encompassing the tasks
> of encoding, processing, and finally decoding for artists and composers
> interested in working with Ambisonics. Regarding the notion of
> completeness, the idea is, if something can be done with Ambisonics, we'd
> like to make that possible with the ATK.
>
> Here's an intro page to the documentation (55 pages!), to give you an
> overview:
>
> http://www.ambisonictoolkit.net/Help/Guides/Intro-to-the-ATK.html
>
>
> And the library browser page:
>
>
> http://www.ambisonictoolkit.net/Help/Browse.html#Libraries%3EAmbisonic%20Toolkit
>
>
>
> I see that you're working with Max/MSP at the moment. Our currently
> release of the ATK is as a SuperCollider library. We've gone w/
> SuperCollider as it gives a tremendous amount of flexibility--as does
> Ambisonics, so we feel they're a good match.
>
> At the moment we haven't implemented HOA features, but there are plans to
> begin with this aspect from January.
>
>
>
> My kind regards,
>
> ~~
> Joseph Anderson
>
> Artist: http://joseph-anderson.org
> Ambisonic Toolkit:  http://ambisonictoolkit.net
>
>
>
>
> On 27 Sep 2012, at 12:45 am, Steven J. Dale wrote:
>
> > Hi all,
> >
> > I'm new to Ambisonics, but very interested in writing music/sound for an
> > installation in this format.
> > I'm getting bits and pieces from many sources, but having a hard time
> > piecing it all together.. I am wondering what's the most economical, DIY
> > way of creating my own array of speakers to get started, and these
> specific
> > questions
> >
> > - Are identical speakers needed for each speaker of the array, or can I
> DIY
> > it buy mixing and matching speakers from old hi/fi and found systems?
> > - I was reading that the exact layout of an HOA is not so important,
> > there's tolerance for different configs, unlike traditional 5.1 channel
> > based systems which have specific locations that they should live in.. if
> > so, what is the determining factor for accurate localization? If I rig up
> > my studio with one config, will it translate to a much larger space by
> > scaling up ? (assuming enough power in the loudspeakers?)
> > - What are ways of writing original music for this format? I use Logic
> and
> > Max... does this format need specific compatible syths/instrument with
> > multiple out, or is the source irrelevant and it's all in the host
> routing?
> > - What's the easiest way of using my existing stereo samples/recordings
> to
> > convert them for use and reproduction ? Is this even possible? If I
> > convert, will I then have to manually 'map' movement across the field?
> >
> > So many questions! If anyone has time, would love to chat with you about
> > all of this  much appreciated.
> >
> > Sounds like a ripe opportunity to create a set of tutorials, podcasts,
> > screencasts of how to get started (if there aren't already)
> >
> > Thanks!
> >
> >
> >  ┈┈
> >  Steven J. Dale  :  projects <http://www.cstreams.com/projects>
> > @lifeinchords <http://www.twitter.com/lifeinchords>
> > sounds<http://soundcloud.com/lifeinchords>
> >  Sound Artist : Designer :  Web Architect
> > -- next part --
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[Sursound] Demo / test piece

[Michael Chapman]

Earlier today, I referred to a slow pan of a symphonic piece.

Perhaps it would be of interest to others :
-as a demo of ambisonic panning (yawing)
-as a 'test' of how smooth it reproduces on rigs.

Would be happy to post it on Ambisonia, if
-any interest
-Aaron ia agreeable(*) and obviously under his
original copyright.

Michael

*It is a derivative of

"Johannes Brahms: Sym No. 1 in c minor, Op. 68, 4th mvt."
Easy enough to 'cook' at home, but it might help newbies ...


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Re: [Sursound] 3D Array

[Joseph Anderson]

Hello Steven,

I'm going to throw in a quick plug for the Ambisonic Toolkit (ATK):

http://ambisonictoolkit.net/

Our goal is to have a complete system conveniently encompassing the tasks of 
encoding, processing, and finally decoding for artists and composers interested 
in working with Ambisonics. Regarding the notion of completeness, the idea is, 
if something can be done with Ambisonics, we'd like to make that possible with 
the ATK.

Here's an intro page to the documentation (55 pages!), to give you an overview:

http://www.ambisonictoolkit.net/Help/Guides/Intro-to-the-ATK.html


And the library browser page:

http://www.ambisonictoolkit.net/Help/Browse.html#Libraries%3EAmbisonic%20Toolkit



I see that you're working with Max/MSP at the moment. Our currently release of 
the ATK is as a SuperCollider library. We've gone w/ SuperCollider as it gives 
a tremendous amount of flexibility--as does Ambisonics, so we feel they're a 
good match.

At the moment we haven't implemented HOA features, but there are plans to begin 
with this aspect from January.



My kind regards,

~~
Joseph Anderson

Artist: http://joseph-anderson.org
Ambisonic Toolkit:  http://ambisonictoolkit.net




On 27 Sep 2012, at 12:45 am, Steven J. Dale wrote:

> Hi all,
> 
> I'm new to Ambisonics, but very interested in writing music/sound for an
> installation in this format.
> I'm getting bits and pieces from many sources, but having a hard time
> piecing it all together.. I am wondering what's the most economical, DIY
> way of creating my own array of speakers to get started, and these specific
> questions
> 
> - Are identical speakers needed for each speaker of the array, or can I DIY
> it buy mixing and matching speakers from old hi/fi and found systems?
> - I was reading that the exact layout of an HOA is not so important,
> there's tolerance for different configs, unlike traditional 5.1 channel
> based systems which have specific locations that they should live in.. if
> so, what is the determining factor for accurate localization? If I rig up
> my studio with one config, will it translate to a much larger space by
> scaling up ? (assuming enough power in the loudspeakers?)
> - What are ways of writing original music for this format? I use Logic and
> Max... does this format need specific compatible syths/instrument with
> multiple out, or is the source irrelevant and it's all in the host routing?
> - What's the easiest way of using my existing stereo samples/recordings to
> convert them for use and reproduction ? Is this even possible? If I
> convert, will I then have to manually 'map' movement across the field?
> 
> So many questions! If anyone has time, would love to chat with you about
> all of this  much appreciated.
> 
> Sounds like a ripe opportunity to create a set of tutorials, podcasts,
> screencasts of how to get started (if there aren't already)
> 
> Thanks!
> 
> 
>  ┈┈
>  Steven J. Dale  :  projects <http://www.cstreams.com/projects>
> @lifeinchords <http://www.twitter.com/lifeinchords>
> sounds<http://soundcloud.com/lifeinchords>
>  Sound Artist : Designer :  Web Architect
> -- next part --
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Re: [Sursound] 3D Array

[Charlie Richmond]

SoundMan-Server is also a good platform for many channel audio (currently
supporting up to 999):

http://www.richmondsounddesign.com/virtual-sound-system.html

Please contact me directly if you would like to get a development licence,
gratis.

Sincerely,
Charlie

* Charlie Richmond - Richmond Sound Design - Skype: charlierichmond
* http://www.RichmondSoundDesign.com
<http://www.richmondsounddesign.com/> "Performance
for the Long Run"
* SoundMan-Server & AudioBox II - Virtual Sound System Core Audio Engine
* LinkedIn & Twitter:
charlierichmond<http://www.linkedin.com/in/charlierichmond> *
Facebook:
charlie.richmond
* G+: 
https://plus.google.com/u/0/117175238910652375011/<https://plus.google.com/u/0/117175238910652375011/posts>
* RSD on Google+: https://plus.google.com/101997019719186030659/
* Primary and much preferred method of communication is via skype
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Re: [Sursound] 3D Array

[Jörn Nettingsmeier]

On 09/27/2012 01:45 AM, Steven J. Dale wrote:


- What are ways of writing original music for this format? I use Logic and
Max... does this format need specific compatible syths/instrument with
multiple out, or is the source irrelevant and it's all in the host routing?


if you're on mac os x or linux, check out ardour with the AMB plugins 
and fons' ambdec. it's the only system on the market that can do 
third-order periphonic busses in a sane way.



- What's the easiest way of using my existing stereo samples/recordings to
convert them for use and reproduction ? Is this even possible? If I
convert, will I then have to manually 'map' movement across the field?


stereo material is quite flexible in an ambisonic context - you can sum 
it to mono or use only one channel for point-like sources, or you can 
spread the two channels as far as you like. this is done simply by 
panning each channel individually. combine it with panning automation, 
and you have very fine control of the image width and clarity.



So many questions! If anyone has time, would love to chat with you about
all of this  much appreciated.


here's a primer targeted specifically at electro-acoustic composers. 
it's very basic and the math is a bit hand-wavey, but it's easy to 
digest, hopefully:

https://stackingdwarves.net/public_stuff/guest_lectures+workshops/2010-11-University_of_Huddersfield/What_can_Ambisonics_do_for_you.pdf

some food for thought when embarking on with-height adventures:
http://lac.linuxaudio.org/2012/speakers?uid=29


--
Jörn Nettingsmeier
Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487

Meister für Veranstaltungstechnik (Bühne/Studio)
Tonmeister VDT

http://stackingdwarves.net

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Re: [Sursound] 3D Array

[Dave Malham]

Hi

On 27 September 2012 01:53, Michael Chapman  wrote:
>
>>
>> - Are identical speakers needed for each speaker of the array, or can I
>> DIY
>> it buy mixing and matching speakers from old hi/fi and found systems?
>
> Don't think anyone would recommend it ... but one has to be
> realistic.

Definitely not to be _recommended_ but, as Michael says, one has to be
realistic. Things to watch out for include not just different sounding
speakers, which DRC would most probably help with,but also polarity
(or, phase as it is generally called in audio, ignoring the frequency
related part of that). Moreover, not just overall polarity which is
easily fixed by reversing the connections. If I remember rightly, some
designs of crossover  reverse the phase of (usually) the midrange unit
to get a flatter frequency response. A mixture of some of those, with
some that have non-phase reversing designs would undoubtably mess
things up. If you have to use mixed speakers (and I have Tannoy Lynx's
in the under audience 4 of our Rymer Auditorium 16 speaker rig, the
rest being Diamond V's) it's probably best to use pairs of matching
speakers on the opposite end of a diameter passing through the central
point, rather than, for instance, distributing them randomly or
placing them next to each other.


>> - I was reading that the exact layout of an HOA is not so important,
>> there's tolerance for different configs, unlike traditional 5.1 channel
>> based systems which have specific locations that they should live in.. if
>> so, what is the determining factor for accurate localization? If I rig up
>> my studio with one config, will it translate to a much larger space by
>> scaling up ? (assuming enough power in the loudspeakers?)
>
> The whole point of ambisonics is that it is independent of the final
> rig.
>

Ahh - within limits! The limit being set by the differences in local
acoustics. It is very difficult, for instance, to get sounds to be
closer than the closest speaker in the rig would sound if a mono sound
was fed to it on its own. Moreover, variations in acoustics local to
the speaker (local reflections, resonances, etc) can distort the
reproduced field. This is why Augustine says you should be prepared
for tweaking of the scaled up version, although this is by no means
always necessary.

>> - What are ways of writing original music for this format? I use Logic and
>> Max... does this format need specific compatible syths/instrument with
>> multiple out, or is the source irrelevant and it's all in the host
>> routing?

Again, Augustine has got it right - Logic into Max. Logic (unless the
latest version has corrected the shortcoming) has real limitations in
terms of input and output configurations both in and of itself, but
also in terms of what multichannel plugins it can use, so using it for
dealing withe the stems and then routing those out to Max (or pD or
Bidule or AudioMulch or...) for Spatial processing and output to the
rig is the way to go - or swap to something like Reaper  which is much
better in this respect..

>> - What's the easiest way of using my existing stereo samples/recordings to
>> convert them for use and reproduction ? Is this even possible? If I
>> convert, will I then have to manually 'map' movement across the field?
>>

On stereo samples - a good starting point is to pan the two channels
into the soundfield with a 60 degree separation in panning position.
This will preserve the image in the stereo, including its movements
(basically you are creating a virtual stereo pair of speakers). Then
experiment! As I always told my students, it is important toknow and
understand what is the technically correct, but you should be prepared
to throw some or all of that that away if necessary because, in the
end, all that matters is how it sounds to your ears.


All the best - and have fun!

   Dave

-- 

These are my own views and may or may not be shared by my employer

Dave Malham
Music Research Centre
Department of Music
The University of York
Heslington
York YO10 5DD
UK
Phone 01904 322448
Fax 01904 322450
'Ambisonics - Component Imaging for Audio'
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