[NewMusic] Core Sound ambisonic mics

[barry threw]

> What's interesting about the Core array is that it's a parallel to
> visual "motion capture" in digital animation, where the director
> can re-plot all the camera work after a performance has been
> recorded by its array of cameras.  The mic system seems like a
> great tool, ideal for one time events (no take 2), and will
> probably get us to the holo-deck a lot sooner.

Can you elaborate on this?  I know < 0 about digital animation, but  
why would you need to "record" with an array of "cameras"?  I assume  
its all virtual...like opengl?

It's possible to reconstruct different camera angles from recordings  
with an array of cameras?

b







> On Nov 7, 2007, at 11:35 AM, cliff caruthers wrote:
>
>> Also, one bidirectional and omni does not equal m/s, even kind of.
>> For the imaging to work properly, has to be a cardioid with with a
>> figure eight...
>> -Cliff
>>
>>
>> On 11/7/07, Matt J. Ingalls <ingalls at mills.edu> wrote:
>>>
>>> barry:
>>> tom is right. soundfield mic is 4 cartiods in a tetrahedron (a-
>>> format),
>>> which is full 3-D. output is usually transcoded (simple  
>>> add&subtract)
>>> to b-format which is
>>> the omni+3 bi-directional (WXYZ) you are talking about.
>>> and i believe this is "1st order" whereas "2nd+ order" is more
>>> channels
>>> added to that..
>>>
>>> -m
>>>
>>> On Wed, 7 Nov 2007, barry threw wrote:
>>>
>>>> You actually need 3 *bi-directional* mics and one omni, and they  
>>>> are
>>>> as close to coincident as possible (without fancy delay  
>>>> processing).
>>>> But, that is only for 3rd order (preserving height information).
>>>>
>>>> For second order you can need 2 bi and one omni; that will give you
>>>> accurate recording of a 2D sound field.
>>>>
>>>> For stereo, all you need is one bi and one omni.  But thats M/S
>>>> (kind
>>>> of) and we all knew about it.
>>>>
>>>> b
>>>>
>>>> On Nov 7, 2007, at 9:45 AM, Tom Duff wrote:
>>>>
>>>>>
>>>>> Just noticed this for recording weenies:
>>>>>
>>>>> http://www.core-sound.com/TetraMic/1.php
>>>>>
>>>>> It's an ambisonic transducer (tetrahedral coincident array of
>>>>> cardioid
>>>>> mics) for under $1000.  Looks great.  Len Moskowitz (Core Sound)
>>>>> usually
>>>>> makes first-rate stuff for the price.
>>>>>
>>>>> Ambisonic recording is extremely cool.  By using 4 directional  
>>>>> mics
>>>>> evenly
>>>>> spaced in 3-D, you can, by appropriate mixing, simulate arbitrary
>>>>> coincident microphone arrays.  If you use a 4-channel recorder,  
>>>>> you
>>>>> can
>>>>> even change miking decisions after the fact.
>>>>>
>>>>> --
>>>>> Tom Duff.  Hwanon ferigeath ge faette scyldas?
>>>>> _______________________________________________
>>>>> Bay Area New Music Discussion Group
>>>>> NewMusic at music.mills.edu
>>>>> http://music.mills.edu/mailman/listinfo/newmusic
>>>>
>>>> Barry Threw
>>>> Media Art and Technology
>>>>
>>>>
>>>> San Francisco, CA     Work: 857-544-3967
>>>> Email: bthrew at gmail.com
>>>> IM: captogreadmore (AIM)
>>>> http:/www.barrythrew.com
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> Bay Area New Music Discussion Group
>>>> NewMusic at music.mills.edu
>>>> http://music.mills.edu/mailman/listinfo/newmusic
>>>>
>>> _______________________________________________
>>> Bay Area New Music Discussion Group
>>> NewMusic at music.mills.edu
>>> http://music.mills.edu/mailman/listinfo/newmusic
>>>
>> _______________________________________________
>> Bay Area New Music Discussion Group
>> NewMusic at music.mills.edu
>> http://music.mills.edu/mailman/listinfo/newmusic
> _______________________________________________
> Bay Area New Music Discussion Group
> NewMusic at music.mills.edu
> http://music.mills.edu/mailman/listinfo/newmusic

Barry Threw
Media Art and Technology


San Francisco, CA Work: 857-544-3967
Email: bthrew at gmail.com
IM: captogreadmore (AIM)
http:/www.barrythrew.com