[Sursound] horizontal-only decoder design for line sources

[Richard Lee]

When I was R&D tea-boy at Wharfedale, I spent time trailing around the country 
with Barry Fox our Promotions Manager, putting on lectures/demos & shows.

Part of the stuff we carted around was the Wharfedale Ambi rig which was

- 12 x TSR110 speakers 
http://www.gramophone.net/Issue/Page/October%201980/126/792093/Wharfedale+Laser+200+and+TSR+110+Loudspeakers
- A souped up Integrex decoder optimised to run a hex system using only 4 
channels of decode and amps
- Calrec Soundfield Mk3a controller
- Rotel RB5000 amp. 100W/channel and still my all time favourite.
- ANOther high powered amp which I can't remember.
- Teac 3440 + stack of Dolby Bs

all to play my Soundfield recordings and some UHJ stuff.  Horizontal only.

The speakers were arranged as top & bottom units with the top sitting upside 
down on the bottom; each precarious pair mounted on quite a tall stand to get 
the speakers above the seated audience.  The idea was to create a line source, 
short at HF where the treble units were close to each other while the 4 bass 
units spanned nearly 1.4m vertically. Our biggest crowd was more than 150 in 
Guildford (IIRC), a foreign city South of Watford.

The huge amp was to implement the system MAG described in the Integrex article 
to use 4 amps to drive 6 speakers in a regular hex.  'W' needs to be nearly 4x 
the power of the other Amps.  I describe a low level version for multichannel 
soundcards at http://ambisonic.info/info/ricardo/decoder.html at the end of the 
section on Classic Ambisonic Decoders.  MAG told me (to my surprise) that it 
was the first practical trial of this method.

The most successful part of the demo was making the soundstage revolve round 
the audience with the Mk3a controller.  Oh.  And the whole she-bang sounded 
good too especially the stuff recorded in Bradford's St. Georges Hall; Sir 
Thomas Beecham's favourite venue.

The biggest problem was making sure all speakers were connected up properly and 
in phase. The supa dupa Ambisonic Surround Decoder MUST have built in 
facilities to facilitate this.
___

The idea behind line sources was to increase the "sweet spot".  To some extent, 
the Wharfedale rig achieved this; good sound and "localisation" even on the 
fringe of the large audience area. A line source avoids (?) the 1/r attenuation 
you get with a point source.  But we also put the speakers as far from the 
audience as possible which might have been a bigger affect.

Conclusions

- I don't think you can get proper line sources unless they span from floor to 
ceiling.
- Even then, all you are doing is putting most of the audience in the "near 
field".

In BLaH2, we used tall Revel Studio Monitors (2 x 8" units arranged vertically 
like the TSR110s) and spent some time trying to determine if we had 1/r with 
them in the listening room.  In most rooms, at frequencies where ceiling & 
floor reflections might help lengthen the "line source", you are well into the 
area of "reflections" so how do you measure 1/r?  In fact measuring 1/r is a 
standard technique to determine how "anechoic" a chamber is.  I don't think we 
had anything approaching a line source for BLaH2

- However I do think even the above poor approximations help with a large 
audience.
- I think standard Classic Ambi Decoder with NFC at the correct frequency for 
the size of the array is appropriate even with these "line sources".
- Probably good to move the "transition from rV to rE" lower down.


The York decoders for large area work are either rE with no Shelfs or the Furse 
"Controlled Opposites" which guarantee no sound from speakers opposite the 
source direction.

I should point out that Controlled Opposites require a fairly even distribution 
of speakers.  If the array is at all wonky, you get some really strange 
decoders.

If anyone else has experience with "line sources" in a horizontal Ambi rig, 
please show & tell.

Or even pseudo pontificating ...
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Re: [Sursound] Masters /PHDs related to surround sound / Sound art in Europe

[Jörn Nettingsmeier]

On 03/19/2011 06:19 PM, Augustine Leudar wrote:

anyone know of any Masters /PHDs related to surround sound / Sound art in
Europe (but not the UK or Ireland - I am already aware of those)


marije baalman (wfs implementation and shapes of virtual sources)
frank melchior (wfs)

googling the following thesis advisors/institutes might put you on some 
hot trails - most publish lists of their students and works:

* iem graz
* institut für audiokommunikation, tu berlin
* telekom labs, tu berlin
* prof. dieter leckschat (fh düsseldorf)
* prof. diemer de vries
* institut für musik und medien, düsseldorf
* erich-thienhaus-institut, hochschule für musik detmold


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Re: [Sursound] horizontal-only decoder design for line sources

[Jörn Nettingsmeier]

On 03/19/2011 10:13 PM, Fons Adriaensen wrote:


Again, the extended cover is the result of carefully shaping the
vertical polar pattern of the array over the range where it intersects
with the the part of the horizontal plane where the listeners are.
It is possible because 'close' listeners are in a differenct direction
(as seen from the array) compared to 'distant' ones.

It is not the result of of any 'near field' effect, or cylindrical
waves.


although it's not really what i was intending to discuss, here goes:

for practical purposes, the only interesting aspect of line arrays is 
that they have very uniform coverage over distance, with reduced level 
loss. i'm a bit out of my depth here mathematically, but my gut feeling 
says that since a) we are not interested in the field outside of the 
arrays, b) we consider horizontal-only ambisonic reproduction, and c) 
and we assume free-field conditions, it is ok to imagine the interior as 
composed of cylindrical waves, because their associated level loss with 
distance is very similar to what an actual line array will deliver.


my point is that the energy distribution of any one speaker array will 
be more even across the listening area than a traditional speaker rig of 
comparable power. which has advantages for the maximum size of ambisonic 
rigs, but which will also bring us into regions of time error where we 
have to reconsider what it is that makes localisation work.


my question was if this affects the ratio of W vs. the rest, and if 
circular harmonics might be a more suitable model for decoder design in 
this case.


*.*

as to the meyer sound page that aaron linked to, well, they are of 
course right to debunk the magical properties attributed to "cylidrical 
waves" by some vendors.
but part of their logic is broken: you don't need a non-linear medium 
for waves to "combine" for all practical purposes, and the superposition 
principle does not invalidate the concept of "coupling".
it's just that one has to consider the bandwidth where this effect is 
dominant, and that lots of other hacks are necessary to make line arrays 
perform well in practice.
but the huygens principle holds, and of course a line of point sources 
can be viewed as coupling to form a linear source, or vice versa.


they contradict their own argument by stating further down that line 
array elements should not be used as singletons. it is of course safe to 
assume that a single line array element does not create a "slice of 
cylindrical wave", but some vendors have waveguiding tricks up their 
sleeves that do just that, although single elements still fail because 
you are more or less always on the boundary. but it is possible to use 
horn reflections in such a way that you will get a hf sound field that 
would appear to be made of several hf tweeters, spaced more closely than 
they actually are. a hack that does not automatically a perfect 
cylindrical wave make, but a damn clever one, and one that moves the 
upper coupling frequency a lot higher than the spacing of the tweeters 
would imply.


more power to meyer for fighting advertising bullshit, but it's not 
quite as simple as that. their problem is that the really clever 
waveguiding stuff is patented like you wouldn't believe - so if your 
company hasn't found a way to circumvent these patents that hasn't 
itself been patented already, you might be tempted ever so slightly to 
deny that clever waveguides exist at all.


i also really dislike their argument that line arrays do not deliver 
-3db due to air absorption, more like -6db. well, doh. of course nobody 
would get their panties in a knot about this simple fact. but 
traditional systems, which are our benchmark, deliver -9db by this 
measuring method - the point is, line arrays throw a hell of a long way 
and kick more or less exactly 3dBs of point source ass. if this could be 
general consensus, i promise to never use the evil "c" word again, and 
suggest 3dBOPSA as an alternative denomination.



--
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] Masters /PHDs related to surround sound / Sound art in Europe

[Frank Melchior]

marije baalman (wfs implementation and shapes of virtual sources)
frank melchior (wfs)

frank melchior (spatial sound design based on measured room impulse 
responses)

to be published in July this year

Best regards, Frank.


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Re: [Sursound] horizontal-only decoder design for line sources

[Fons Adriaensen]

On Sun, Mar 20, 2011 at 11:21:41AM +0100, Jörn Nettingsmeier wrote:

> my question was if this affects the ratio of W vs. the rest, and if  
> circular harmonics might be a more suitable model for decoder design in  
> this case.

The answer to that IMHO is no, for the reasons stated earlier.

> but part of their logic is broken: you don't need a non-linear medium  
> for waves to "combine" for all practical purposes,

Depends on what you call 'combine'. If the result of driving 
all elements is different from the sum of their individual
results, that is non-linear by definition.

> and the superposition  
> principle does not invalidate the concept of "coupling".

What is this 'coupling' ? You mean one driver's response
being modified by the presence of others ? This is again
a purely linear effect (if not you have other problems).
It has to be taken into account when finding the indivual
responses of each unit. Again nothing magical, just the
correct way to do superposition.

> but the huygens principle holds, and of course a line of point sources  
> can be viewed as coupling to form a linear source, or vice versa.

Up to some frequency (determined by the spacing of the point
sources) that is a valid approximation. It's just superposition,
nothing else. Again what is this magical 'coupling' ?

> they contradict their own argument by stating further down that line  
> array elements should not be used as singletons. it is of course safe to  
> assume that a single line array element does not create a "slice of  
> cylindrical wave", but some vendors have waveguiding tricks up their  
> sleeves that do just that, although single elements still fail because  
> you are more or less always on the boundary. but it is possible to use  
> horn reflections in such a way that you will get a hf sound field that  
> would appear to be made of several hf tweeters, spaced more closely than  
> they actually are. a hack that does not automatically a perfect  
> cylindrical wave make, but a damn clever one, and one that moves the  
> upper coupling frequency a lot higher than the spacing of the tweeters  
> would imply.

Yes, such techniques do exists. Assume for a moment that they
work as claimed, and that the complete 3.5 meters of stacked
drivers do indeed behave as real line source and produce
cylindrical waves in the listening area.

It would be unusable: extremely bad FR, even on axis and
dependent on distance. And even 10 degrees of-axis it gets
much worse again - you'd have a real pencil beam at HF.
It's OK-ish exaclty on-axis and at a distance of 40 m
or so, but no amount of EQ or whatever is going to make
it usable at closer range.

To be usable, you'd have to 'splay' the array (and put it
on a tower). This will provide a uniform response if done
correctly, and at close range it will still drop off less
than 6 dB when distance is doubled. But not because of any
cylindrical waves or any 2-D effect, but just because
such a splayed array emulates a more distant point source.
It still needs EQ, close to +3dB/oct. In practice a large
part of this is taken care of by making individual drivers
more directional as frequency goes up. Which does indeed 
mean they wouldn't make very good speakers when used
individually.

Ciao,

-- 
FA

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[Sursound] Ambisonics max/MSP 8 speakers - ICST Ambisonic Externals

[Darren - Bradley]

Darren here,

thanks for all your help, much appreciated.

I have consulted my friends and we think maybe a 8 speaker setup is  
best for our audience we are going to perform from 40 to 300 people


We are looking at now using max/MSP with 8 speakers and using routing  
of 4 sends in different panning postions from 'LIVE' to max/MSP.


Does any one have a good patch for max/MSP or is the help file  
ambiencode~ and ambidecode~  enough  taken from - icst website  >  
Ambisonics Externals for MaxMSP " and would this be best to use.


Cheers
Darren
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Re: [Sursound] Masters /PHDs related to surround sound / Sound art in Europe

[Augustine Leudar]

Thanks for the replies,
just to clarify - I am looking to do a masters or PHD or Masters myself in
Europe in this area and am enquiring as to what courses are available,
cheers,
Gus
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Re: [Sursound] horizontal-only decoder design for line sources

[Jörn Nettingsmeier]

On 03/20/2011 04:52 PM, Fons Adriaensen wrote:

On Sun, Mar 20, 2011 at 11:21:41AM +0100, Jörn Nettingsmeier wrote:

What is this 'coupling' ?


just a frequently used technical term used by p.a. systems engineers to 
describe the plain simple fact that a reasonably high number of point 
sources reasonably close together will begin to resemble a line source 
for a limited frequency range over a limited distance, with the 
associated advantages for directivity and throw. aka huygens' principle.

no magic whatsoever, and no non-linearities required.

the trick with line arrays is to know for which bands you can exploit 
which tricks. the superposition model tends to work well for the low and 
midrange (provided you use sufficiently long arrays), and you fix the hf 
response (which is indeed made of individual narrow beams) by gracious 
application of eq, by splaying the array, and by driving portions of the 
array with slightly different signals.


so a downfill extension, which has much wider vertical coverage to fix 
the FR for people close to the stage, will still be part of the 
effective line length for lower frequencies.


btw, it is not strictly true that you splay the array to emulate a more 
distant point source. arrays are almost never splayed along a circular 
section. usually, the main part retains a strictly linear shape (which 
will usually be tilted down as a whole), and you only curve the lower 
part, to fill in the closer range, resulting in the well-known "J" 
shape. hf directivity is usually reduced for the downfills (25° vs. 5° 
is not an uncommon figure), and you usually eq them differently and 
sometimes reduce their output power to ensure uniform coverage, 
depending on the height of the available anchor points.




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

Meister für Veranstaltungstechnik (Bühne/Studio)
Tonmeister VDT

http://stackingdwarves.net

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Re: [Sursound] Ambisonics max/MSP 8 speakers - ICST Ambisonic Externals

[Jörn Nettingsmeier]

On 03/20/2011 06:03 PM, Darren - Bradley wrote:

Darren here,

thanks for all your help, much appreciated.

I have consulted my friends and we think maybe a 8 speaker setup is best
for our audience we are going to perform from 40 to 300 people

We are looking at now using max/MSP with 8 speakers and using routing of
4 sends in different panning postions from 'LIVE' to max/MSP.

Does any one have a good patch for max/MSP or is the help file
ambiencode~ and ambidecode~ enough taken from - icst website >
Ambisonics Externals for MaxMSP " and would this be best to use.


if you're using mac os, i'd recommend you try fons' ambdec decoder. not 
too hard to build for osx, and maybe someone here has already created a 
package they might be willing to share?


it outperforms other decoders i've heard, and it's quite easy to use. 
there is a preset for third-order octagons, and all you need to change 
are the speaker distances. you really want to use third-order panning.


best,

jörn



--
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] horizontal-only decoder design for line sources

[Dave Hunt]

Hi,



Date: Sun, 20 Mar 2011 15:52:55 +
From: Fons Adriaensen 

On Sun, Mar 20, 2011 at 11:21:41AM +0100, J?rn Nettingsmeier wrote:



and the superposition
principle does not invalidate the concept of "coupling".


What is this 'coupling' ? You mean one driver's response
being modified by the presence of others ? This is again
a purely linear effect (if not you have other problems).
It has to be taken into account when finding the indivual
responses of each unit. Again nothing magical, just the
correct way to do superposition.

but the huygens principle holds, and of course a line of point  
sources

can be viewed as coupling to form a linear source, or vice versa.


Up to some frequency (determined by the spacing of the point
sources) that is a valid approximation. It's just superposition,
nothing else. Again what is this magical 'coupling' ?


they contradict their own argument by stating further down that line
array elements should not be used as singletons. it is of course  
safe to

assume that a single line array element does not create a "slice of
cylindrical wave", but some vendors have waveguiding tricks up their
sleeves that do just that, although single elements still fail  
because
you are more or less always on the boundary. but it is possible to  
use
horn reflections in such a way that you will get a hf sound field  
that
would appear to be made of several hf tweeters, spaced more  
closely than

they actually are. a hack that does not automatically a perfect
cylindrical wave make, but a damn clever one, and one that moves the
upper coupling frequency a lot higher than the spacing of the  
tweeters

would imply.


Yes, such techniques do exists. Assume for a moment that they
work as claimed, and that the complete 3.5 meters of stacked
drivers do indeed behave as real line source and produce
cylindrical waves in the listening area.

It would be unusable: extremely bad FR, even on axis and
dependent on distance. And even 10 degrees of-axis it gets
much worse again - you'd have a real pencil beam at HF.
It's OK-ish exaclty on-axis and at a distance of 40 m
or so, but no amount of EQ or whatever is going to make
it usable at closer range.

To be usable, you'd have to 'splay' the array (and put it
on a tower). This will provide a uniform response if done
correctly, and at close range it will still drop off less
than 6 dB when distance is doubled. But not because of any
cylindrical waves or any 2-D effect, but just because
such a splayed array emulates a more distant point source.
It still needs EQ, close to +3dB/oct. In practice a large
part of this is taken care of by making individual drivers
more directional as frequency goes up. Which does indeed
mean they wouldn't make very good speakers when used
individually.


The whole PA world has gone rather line-array mad since the idea was  
re-introduced and re-engineered by L'Acoustique and Intellivox (Duran  
Audio) some 10-12 years ago. Now, every manufacturer has to have a   
"line-array" system, though the use of the term is often barely  
appropriate. Initially the systems were for very large spaces, with  
long lines, but over time there has been a desire for smaller  
systems, sometimes to almost ridiculous extremes (see K-Array).


L'Acoustique produced well engineered, powerful, and good sounding  
systems that were scalable, and everyone else (apart from some like  
Tony Andrews of Function One) has followed. The fact that they were  
well engineered, powerful, and good sounding probably convinced the  
world that this was "a good thing" almost as much as the controlled  
vertical dispersion (at mid to HF) which resulted in reduced  
reflections from unwanted directions. L'Acoustique had made a range  
of good sounding, compact and powerful PA speakers for some time  
under the Heil brand name, though these were not really known outside  
France. They claim 5 degree vertical dispersion for their mid/HF  
boxes, something I have doubts about for an individual element though  
the arraying and 'coupling' may contribute to this claim.


The arrays were always what became termed "J" arrays, nearly vertical  
at the top, with more boxes, and curved towards the bottom to cover  
"the near field" with fewer boxes. Thus there was more energy at  
higher frequencies radiated to more distant listeners, otherwise  
known as 'good throw". Each box had its own amplifier, and current  
systems have amplifiers with DSP to provide cross-overs, equalisers  
and delay in the cabinet, all controllable by a laptop over a  
network, to allow "steering" of the entire array.


The term "line array"  also covers a 2D implementation of  speaker  
(or microphone) array under DSP control.


Smaller "line array" systems are a response to the demand for buzz  
word technology on a smaller scale. d&b systems, for example, are  
sold as stackable and scalable, and individual elements are  widely  
used singly as well as in larger arrays. They are very usable.

Re: [Sursound] Ambisonics max/MSP 8 speakers - ICST Ambisonic Externals

[Hector Centeno]

Hello Darren,

I second jörn, ambdec is the way to go. I've just recently tested it
against ambidecode~ and IRCAM's spat.decoder~ object and I found
ambdec to produce a much better result overall. I've compiled it under
Mac OSX 10.6.6 but I remember having to tweak something in the make
file for ambdec or maybe one of the needed libraries. I could try to
build a package later today or tomorrow.

Best,

Hector


2011/3/20 Jörn Nettingsmeier :
> On 03/20/2011 06:03 PM, Darren - Bradley wrote:
>>
>> Darren here,
>>
>> thanks for all your help, much appreciated.
>>
>> I have consulted my friends and we think maybe a 8 speaker setup is best
>> for our audience we are going to perform from 40 to 300 people
>>
>> We are looking at now using max/MSP with 8 speakers and using routing of
>> 4 sends in different panning postions from 'LIVE' to max/MSP.
>>
>> Does any one have a good patch for max/MSP or is the help file
>> ambiencode~ and ambidecode~ enough taken from - icst website >
>> Ambisonics Externals for MaxMSP " and would this be best to use.
>
> if you're using mac os, i'd recommend you try fons' ambdec decoder. not too
> hard to build for osx, and maybe someone here has already created a package
> they might be willing to share?
>
> it outperforms other decoders i've heard, and it's quite easy to use. there
> is a preset for third-order octagons, and all you need to change are the
> speaker distances. you really want to use third-order panning.
>
> best,
>
> jörn
>
>
>
> --
> 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] horizontal-only decoder design for line sources

[Jörn Nettingsmeier]

On 03/20/2011 07:25 PM, Dave Hunt wrote:

The whole PA world has gone rather line-array mad since the idea was
re-introduced and re-engineered by L'Acoustique and Intellivox (Duran
Audio) some 10-12 years ago.


mostly for two reasons:
* they are cheaper than designs with delay towers
* with their better directivity, you can get reasonably good sound out 
of mediocre or outright bad-sounding halls, where stacks would be very 
hard to get right (since you can effectively reduce room excitation or 
even steer around problematic walls altogether)


my subjective view is that you can also scale them higher than stacked 
systems before they start to sound really funny.


and of course they are a lot easier and safer to rig, and to get really 
high up in the air, which is totally uneconomical for stacks.



Now, every manufacturer has to have a
"line-array" system, though the use of the term is often barely
appropriate.


true. not the least because l'acoustic and a select few other players 
have patented all the really clever bits, and the objective of the race 
has changed to "whose patent workarounds are the least detrimental?"



I too, like J?rn, am curious to know at what point does ambisonics break
due to the non-simultaneity of arrival of sound from widely spaced
sources. Obviously lower order components will suffer most from this,


why do you think that?


With a widely spaced array, the "sweet spot" will be correspondingly
larger,


that's not really true. the sweet spot in the strict ambisonic sense is 
a function of order and wavelength only. but intuitively, i think the 
same. my rule of thumb to the question of how many tickets can be sold 
without falling from grace is "two thirds of the array diameter at third 
order", since it does indeed seem that large arrays are more lenient in 
this respect.
even under lab conditions, the effect is obvious: fons once gave me a 
"virtual ambisonic" demo with point sources rendered on the sala bianca 
wfs system (using material i was intimately familiar with), and the 
result was clearly improved by moving the virtual sources well behind 
the physical wfs speakers.

i guess the explanation is that we get closer to the plane wave ideal.


and thus a bigger audience can be within it, but the ultimate
constraints will be size of venue and environmental noise concerns.


that's another thing worth exploring: the funktion one guys have 
reported that ambi rigs have an advantage in this respect, because the 
ratio of useful loudness inside to leaked emission outside of the array 
is better than with stereo (or maybe even conventional four-point) 
playback systems. i haven't experienced this yet and can't think of a 
hypothesis to explain it, but i'd like to talk to the f1 guys at some 
point about this observation.



--
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] Ambisonics max/MSP 8 speakers - ICST Ambisonic Externals

[umashankar mantravadi]

has anyone packaged fons ambdec (and even his tetraproc) so i can install it 
easily on ubuntu studio?
 
umashankar

i have published my poems. read (or buy) at http://stores.lulu.com/umashankar


 
> Date: Sun, 20 Mar 2011 19:11:03 +0100
> From: netti...@stackingdwarves.net
> To: sursound@music.vt.edu
> Subject: Re: [Sursound] Ambisonics max/MSP 8 speakers - ICST Ambisonic 
> Externals
> 
> On 03/20/2011 06:03 PM, Darren - Bradley wrote:
> > Darren here,
> >
> > thanks for all your help, much appreciated.
> >
> > I have consulted my friends and we think maybe a 8 speaker setup is best
> > for our audience we are going to perform from 40 to 300 people
> >
> > We are looking at now using max/MSP with 8 speakers and using routing of
> > 4 sends in different panning postions from 'LIVE' to max/MSP.
> >
> > Does any one have a good patch for max/MSP or is the help file
> > ambiencode~ and ambidecode~ enough taken from - icst website >
> > Ambisonics Externals for MaxMSP " and would this be best to use.
> 
> if you're using mac os, i'd recommend you try fons' ambdec decoder. not 
> too hard to build for osx, and maybe someone here has already created a 
> package they might be willing to share?
> 
> it outperforms other decoders i've heard, and it's quite easy to use. 
> there is a preset for third-order octagons, and all you need to change 
> are the speaker distances. you really want to use third-order panning.
> 
> 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
  
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Re: [Sursound] Ambisonics max/MSP 8 speakers - ICST Ambisonic Externals

[Marc Lavallée]

umashankar,

You can install ambdec from the Main KXStudio PPA repository :
https://launchpad.net/~kxstudio-team

-- 
Marc

Le 20 mars 2011, umashankar mantravadi a écrit :
> has anyone packaged fons ambdec (and even his tetraproc) so i can install
> it easily on ubuntu studio?
>
> umashankar
>
> i have published my poems. read (or buy) at
> http://stores.lulu.com/umashankar
>
> > Date: Sun, 20 Mar 2011 19:11:03 +0100
> > From: netti...@stackingdwarves.net
> > To: sursound@music.vt.edu
> > Subject: Re: [Sursound] Ambisonics max/MSP 8 speakers - ICST Ambisonic
> > Externals
> >
> > On 03/20/2011 06:03 PM, Darren - Bradley wrote:
> > > Darren here,
> > >
> > > thanks for all your help, much appreciated.
> > >
> > > I have consulted my friends and we think maybe a 8 speaker setup is
> > > best for our audience we are going to perform from 40 to 300 people
> > >
> > > We are looking at now using max/MSP with 8 speakers and using routing
> > > of 4 sends in different panning postions from 'LIVE' to max/MSP.
> > >
> > > Does any one have a good patch for max/MSP or is the help file
> > > ambiencode~ and ambidecode~ enough taken from - icst website >
> > > Ambisonics Externals for MaxMSP " and would this be best to use.
> >
> > if you're using mac os, i'd recommend you try fons' ambdec decoder. not
> > too hard to build for osx, and maybe someone here has already created a
> > package they might be willing to share?
> >
> > it outperforms other decoders i've heard, and it's quite easy to use.
> > there is a preset for third-order octagons, and all you need to change
> > are the speaker distances. you really want to use third-order panning.
> >
> > 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
>
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Re: [Sursound] Ambisonics max/MSP 8 speakers - ICST Ambisonic Externals

[Hector Centeno]

OK. I made an installer for ambdec for Mac OS X. Please feel free to
contact me off-list if anyone needs it. It's not tested but I think it
should work. The only problem might be that I missed a shared library,
which I can fix. JackOSX is required.

Best,

Hector

Note to Fons: I took care of adding a note saying that no
responsibility or technical support will be expected from you
regarding this package.



On Sun, Mar 20, 2011 at 2:45 PM, Hector Centeno  wrote:
> Hello Darren,
>
> I second jörn, ambdec is the way to go. I've just recently tested it
> against ambidecode~ and IRCAM's spat.decoder~ object and I found
> ambdec to produce a much better result overall. I've compiled it under
> Mac OSX 10.6.6 but I remember having to tweak something in the make
> file for ambdec or maybe one of the needed libraries. I could try to
> build a package later today or tomorrow.
>
> Best,
>
> Hector
>
>
> 2011/3/20 Jörn Nettingsmeier :
>> On 03/20/2011 06:03 PM, Darren - Bradley wrote:
>>>
>>> Darren here,
>>>
>>> thanks for all your help, much appreciated.
>>>
>>> I have consulted my friends and we think maybe a 8 speaker setup is best
>>> for our audience we are going to perform from 40 to 300 people
>>>
>>> We are looking at now using max/MSP with 8 speakers and using routing of
>>> 4 sends in different panning postions from 'LIVE' to max/MSP.
>>>
>>> Does any one have a good patch for max/MSP or is the help file
>>> ambiencode~ and ambidecode~ enough taken from - icst website >
>>> Ambisonics Externals for MaxMSP " and would this be best to use.
>>
>> if you're using mac os, i'd recommend you try fons' ambdec decoder. not too
>> hard to build for osx, and maybe someone here has already created a package
>> they might be willing to share?
>>
>> it outperforms other decoders i've heard, and it's quite easy to use. there
>> is a preset for third-order octagons, and all you need to change are the
>> speaker distances. you really want to use third-order panning.
>>
>> 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
>>
>
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Re: [Sursound] Ambisonics max/MSP 8 speakers - ICST Ambisonic Externals

[umashankar mantravadi]

thank you. i will try it tonight
umashankar

i have published my poems. read (or buy) at http://stores.lulu.com/umashankar


 
> From: m...@hacklava.net
> To: sursound@music.vt.edu
> Date: Sun, 20 Mar 2011 22:36:37 -0400
> Subject: Re: [Sursound] Ambisonics max/MSP 8 speakers - ICST Ambisonic 
> Externals
> 
> umashankar,
> 
> You can install ambdec from the Main KXStudio PPA repository :
> https://launchpad.net/~kxstudio-team
> 
> -- 
> Marc
> 
> Le 20 mars 2011, umashankar mantravadi a écrit :
> > has anyone packaged fons ambdec (and even his tetraproc) so i can install
> > it easily on ubuntu studio?
> >
> > umashankar
> >
> > i have published my poems. read (or buy) at
> > http://stores.lulu.com/umashankar
> >
> > > Date: Sun, 20 Mar 2011 19:11:03 +0100
> > > From: netti...@stackingdwarves.net
> > > To: sursound@music.vt.edu
> > > Subject: Re: [Sursound] Ambisonics max/MSP 8 speakers - ICST Ambisonic
> > > Externals
> > >
> > > On 03/20/2011 06:03 PM, Darren - Bradley wrote:
> > > > Darren here,
> > > >
> > > > thanks for all your help, much appreciated.
> > > >
> > > > I have consulted my friends and we think maybe a 8 speaker setup is
> > > > best for our audience we are going to perform from 40 to 300 people
> > > >
> > > > We are looking at now using max/MSP with 8 speakers and using routing
> > > > of 4 sends in different panning postions from 'LIVE' to max/MSP.
> > > >
> > > > Does any one have a good patch for max/MSP or is the help file
> > > > ambiencode~ and ambidecode~ enough taken from - icst website >
> > > > Ambisonics Externals for MaxMSP " and would this be best to use.
> > >
> > > if you're using mac os, i'd recommend you try fons' ambdec decoder. not
> > > too hard to build for osx, and maybe someone here has already created a
> > > package they might be willing to share?
> > >
> > > it outperforms other decoders i've heard, and it's quite easy to use.
> > > there is a preset for third-order octagons, and all you need to change
> > > are the speaker distances. you really want to use third-order panning.
> > >
> > > 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
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