Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[Robert Greene]

Sorry! I read the wrong volume! RFH is actually 21,960.
This gives critical distance ~ 7 meters.
(not that this changes my basic point but just for the record)
Robert

On Wed, 22 May 2013, Robert Greene wrote:



No. But the fact that a hall sounds
anechoic or nearly so does not mean it is!
To the extent that I could find out on line
in a quick search, it seems that the
reverb time was about 1.4 seconds. This
is much too short to sound satisfactory and
moreover the rise of RT in the bass was
not much--this is something that makes
a hall sound thin and cold(like Disney in LA--
there is a lot of reverb there, 2 sec time but
it is unifomr with respect to frequency--
the thing sounds like a bad audio system)

However, while this is surely too dry to be
a good hall, such a reverb time will still
lead to the reverberant sound field dominating
the total energy received. One just has to back up
a bit further before this happens--but it will
still happen at all but extremely close locations.

For a fixed volume, the critical distance(beyond which
reverb is more than half the sound) varies reciprocally with
the square root of the reverb time. If the hall had a
reverb time of 2.8 seconds(super wet) then the critical distance
would be changed only by a factor of 1.4. ALLL halls that
are not open to the out of doors have a critical distance that
is smaller than the distance to most audience locations.

A quick seat of the pants calculation for RFH (volume 11,600
cu m, rt 1.4) gives that the critical distane is around 5.5 meters.
Not that far! Beyond that distance, reverb field is more than direct arrival.

Because of the precedence effect, the sound seems to come straight from
the players. But if is an illusion!
CF
www.regonaudio.com
"Records and Reality"

The relevance to the live versus speaker demo is that at distance,
the power response of the speaker dominates the scene--the specific
radiation pattern is not so important in detail. Which is why
the AR demos worked! (and presumably the Wharf. ones as well)

Robert

On Tue, 21 May 2013, David Pickett wrote:


At 12:16 21-05-13, Robert Greene wrote:


Even "dead" concert halls in the relative sense
have a lot of reverberation. A really dead hall
still has a 1 second reverberation time say
and most of what you hear in the audience is still
reverberant sound.


Did you ever hear an orchestra playing in the RFH pre 1960???

David

___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound


___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound


___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound

Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[Robert Greene]

No. But the fact that a hall sounds
anechoic or nearly so does not mean it is!
To the extent that I could find out on line
in a quick search, it seems that the
reverb time was about 1.4 seconds. This
is much too short to sound satisfactory and
moreover the rise of RT in the bass was
not much--this is something that makes
a hall sound thin and cold(like Disney in LA--
there is a lot of reverb there, 2 sec time but
it is unifomr with respect to frequency--
the thing sounds like a bad audio system)

However, while this is surely too dry to be
a good hall, such a reverb time will still
lead to the reverberant sound field dominating
the total energy received. One just has to back up
a bit further before this happens--but it will
still happen at all but extremely close locations.

For a fixed volume, the critical distance(beyond which
reverb is more than half the sound) varies reciprocally with
the square root of the reverb time. If the hall had a
reverb time of 2.8 seconds(super wet) then the critical distance
would be changed only by a factor of 1.4. ALLL halls that
are not open to the out of doors have a critical distance that
is smaller than the distance to most audience locations.

A quick seat of the pants calculation for RFH (volume 11,600
cu m, rt 1.4) gives that the critical distane is around 5.5 meters.
Not that far! Beyond that distance, reverb field is more than direct 
arrival.


Because of the precedence effect, the sound seems to come straight from
the players. But if is an illusion!
CF
www.regonaudio.com
"Records and Reality"

The relevance to the live versus speaker demo is that at distance,
the power response of the speaker dominates the scene--the specific
radiation pattern is not so important in detail. Which is why
the AR demos worked! (and presumably the Wharf. ones as well)

Robert

On Tue, 21 May 2013, David Pickett wrote:


At 12:16 21-05-13, Robert Greene wrote:


Even "dead" concert halls in the relative sense
have a lot of reverberation. A really dead hall
still has a 1 second reverberation time say
and most of what you hear in the audience is still
reverberant sound.


Did you ever hear an orchestra playing in the RFH pre 1960???

David

___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound


___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound

Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[David Pickett]

At 12:16 21-05-13, Robert Greene wrote:


Even "dead" concert halls in the relative sense
have a lot of reverberation. A really dead hall
still has a 1 second reverberation time say
and most of what you hear in the audience is still
reverberant sound.


Did you ever hear an orchestra playing in the RFH pre 1960???

David

___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound

Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[Robert Greene]

Even "dead" concert halls in the relative sense
have a lot of reverberation. A really dead hall
still has a 1 second reverberation time say
and most of what you hear in the audience is still
reverberant sound.
Robert

On Mon, 20 May 2013, David Pickett wrote:


At 00:50 18-05-13, Robert Greene wrote:


Of course in those live versus canned experiments(also with AR)
reverberation tended to make things sound pretty much the same
to smooth out errors and so on.


Reverberation in the RFH pre 1966?

David

___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound


___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound

Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[David Pickett]

At 00:50 18-05-13, Robert Greene wrote:


Of course in those live versus canned experiments(also with AR)
reverberation tended to make things sound pretty much the same
to smooth out errors and so on.


Reverberation in the RFH pre 1966?

David

___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound

Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[Rev Tony Newnham]

Hi

That's not the RFH - nor RAH!  The stage & organ are wrong for both.

Every Blessing

Tony

> -Original Message-
> From: sursound-boun...@music.vt.edu [mailto:sursound-boun...@music.vt.edu]
On
> Behalf Of Aaron Heller
> Sent: 19 May 2013 20:18
> To: Surround Sound discussion group
> Subject: Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots
of
> mics.
> 
> 
> There's a photo of the set up at Royal Festival Hall, about 1/3 down on
this
> page
> 
> http://www.gearplus.com.au/products/wharfedale/history/0-history-
> wharfedale.htm

___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound

Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[John Leonard]

Looks like The Duke's Hall at the Royal Academy Of Music.

John

On 19 May 2013, at 21:19, Paul Hodges  wrote:

> Only if there's another Festival Hall which I don't know about!  Sure, some 
> demos took place there (four out of over twenty), but that photo sure ain't 
> of one of them (even though it is so labelled in Wharfedale's own brochures)!

___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound

Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[Paul Hodges]

--On 19 May 2013 12:18 -0700 Aaron Heller  wrote:


There's a photo of the set up at Royal Festival Hall, about 1/3 down on
this page

http://www.gearplus.com.au/products/wharfedale/history/0-history-wharfeda
le.htm


Only if there's another Festival Hall which I don't know about!  Sure, some 
demos took place there (four out of over twenty), but that photo sure ain't 
of one of them (even though it is so labelled in Wharfedale's own 
brochures)!


Paul

--
Paul Hodges


___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound

Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[Aaron Heller]

On Sat, May 18, 2013 at 3:01 AM, Rev Tony Newnham <
revtonynewn...@blueyonder.co.uk> wrote:

> Indeed - there's a picture or two in one of his books, which I have here
> somewhere.  I don't think he tried to mimic the piositions of instruments
> within an ensemble though - except maybe the piano.  No time to look it up
> at present 

There's a photo of the set up at Royal Festival Hall, about 1/3 down on
this page

http://www.gearplus.com.au/products/wharfedale/history/0-history-wharfedale.htm
-- next part --
An HTML attachment was scrubbed...
URL: 

___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound

Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[Augustine Leudar]

You see if he didnt do this (mimic positions of instruments)  - its a very
different thing.

On 18 May 2013 12:01, Rev Tony Newnham wrote:

> Hi
>
> Indeed - there's a picture or two in one of his books, which I have here
> somewhere.  I don't think he tried to mimic the piositions of instruments
> within an ensemble though - except maybe the piano.  No time to look it up
> at present 
>
> Every Blessing
>
> Tony
>
> > -Original Message-
> > From: sursound-boun...@music.vt.edu [mailto:
> sursound-boun...@music.vt.edu]
> On
> > Behalf Of Gerard Lardner
> > Sent: 18 May 2013 01:23
> > To: sursound@music.vt.edu
> > Subject: Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with
> lots
> of
> > mics.
> >
> > I believe Gilbert Briggs of Wharfedale did something like this in the
> 1950s.
> > He hired major concert halls and other public venues in the UK and USA to
> give
> > concerts comparing live with recorded sound.
>
> ___
> Sursound mailing list
> Sursound@music.vt.edu
> https://mail.music.vt.edu/mailman/listinfo/sursound
>



-- 
07580951119

augustine.leudar.com
-- next part --
An HTML attachment was scrubbed...
URL: 
<https://mail.music.vt.edu/mailman/private/sursound/attachments/20130519/abd4350c/attachment.html>
___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound

Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[Rev Tony Newnham]

Hi

Indeed - there's a picture or two in one of his books, which I have here
somewhere.  I don't think he tried to mimic the piositions of instruments
within an ensemble though - except maybe the piano.  No time to look it up
at present 

Every Blessing

Tony

> -Original Message-
> From: sursound-boun...@music.vt.edu [mailto:sursound-boun...@music.vt.edu]
On
> Behalf Of Gerard Lardner
> Sent: 18 May 2013 01:23
> To: sursound@music.vt.edu
> Subject: Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots
of
> mics.
> 
> I believe Gilbert Briggs of Wharfedale did something like this in the
1950s.
> He hired major concert halls and other public venues in the UK and USA to
give
> concerts comparing live with recorded sound. 

___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound

Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[Robert Greene]

I think I did not make myself clear.
Of course in those live versus canned experiments(also with AR)
reverberation tended to make things sound pretty much the same
to smooth out errors and so on.
But in fact, if one records  musical instrument with a mike
and plays it back with a speaker has no hope at all of
hearing the sound of the instrument as it really was--
except on one axis anechoically.
This just won't happen. Except if one recorded
the power response of the instrument and plays it back
with a constant power response speaker in a highly reverberant
environment.
Real musical instruments are extremely far from being omni
radiators. There is no chance of duplicating their patterns
with a speaker and no determined axis on which the recording
should be done.
Music is a rapidly changing thing and one can get away
with a certain amount of error especially in switching
in the middle of music --because the brain becomes
engaged with the music and expects it to continue
sounding as it was sounding.
Wharf. and AR experiments were interesting
but they were a bit of a cheat--reverberant environment
in particular.
But if one looks at what really happens, this clearly
will not work in real truth. An honest experimment
designed to maximize not minimize discrimination would
bomb completely.

Basically a  speaker will do the job of sounding like
an instrument in only two cases
1 an aenchoic environment- on axis is everything
or
2 an extremely reverberant environment, in which
power response dominates. Record the power response
of the instrument and bingo.

In any circumstances in between, it is a fake though
one might be able to fool people with music material
(which is born to fake people out, so ingrained
are the  perception patterns).

Look at that link, at how a violin actually radiates sound
(or similar diagrams for other instruments) No speaker
can duplicate the patern which is complex and varies with frequency.
One would have to have a multiple-pole speaker and a lot of channels
of recording of the instrument along various axes.
The whole thing would be like Ambisonics in reverse--lots
of channels needed to make it work.
That would work of course.

Robert

On Sat, 18 May 2013, Gerard Lardner wrote:

I believe Gilbert Briggs of Wharfedale did something like this in the 1950s. 
He hired major concert halls and other public venues in the UK and USA to 
give concerts comparing live with recorded sound. Of course, the purpose was 
to promote his Wharfedale loudspeakers and Quad amplifiers (he and Peter 
Walker of Quad were friends), but the events were apparently sold out well in 
advance. I'm sure I have a reference somewhere in one of Briggs' books.



On 17/05/2013 16:53, Augustine Leudar wrote:

Dear Robert - what I am talking about has nothing to do with the
multimicing of orchestras etc which are used to subsequently produce stereo
recordings, 5.1 etc - and it has not been sold to the public by the music
industry at all on account of the fact that to listen to it the  public
would need a lifesize replica of the space the sound installation was
designed for (in this case a church and a bar ) , a multichannel soundcard
they would be unlikely to know how to operate and about 20 very irregularly
spaced speakers.
However I dont see why it wouldnt work for musical instruments as well - as
long as the speakers were placed in exactly the same place as the
instruments were recorded in and the mics didnt pick up any other
instrument apart from the one they are meant to record . I guess instead of
the musicians in the orchestra you would have speakers sitting in their
place - but you would still need an orchestral hall and the speakers would
still need to be in exactly the same places the musicians were sitting - Im
sure somebody must have  tried this - again not something you can listen to
in the living room.



___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound


___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound

Re: [Sursound] [allowed] Re: Recreating a 3d soundfield with lots of mics.....

[Gerard Lardner]

I believe Gilbert Briggs of Wharfedale did something like this in the 
1950s. He hired major concert halls and other public venues in the UK 
and USA to give concerts comparing live with recorded sound. Of course, 
the purpose was to promote his Wharfedale loudspeakers and Quad 
amplifiers (he and Peter Walker of Quad were friends), but the events 
were apparently sold out well in advance. I'm sure I have a reference 
somewhere in one of Briggs' books.



On 17/05/2013 16:53, Augustine Leudar wrote:

Dear Robert - what I am talking about has nothing to do with the
multimicing of orchestras etc which are used to subsequently produce stereo
recordings, 5.1 etc - and it has not been sold to the public by the music
industry at all on account of the fact that to listen to it the  public
would need a lifesize replica of the space the sound installation was
designed for (in this case a church and a bar ) , a multichannel soundcard
they would be unlikely to know how to operate and about 20 very irregularly
spaced speakers.
However I dont see why it wouldnt work for musical instruments as well - as
long as the speakers were placed in exactly the same place as the
instruments were recorded in and the mics didnt pick up any other
instrument apart from the one they are meant to record . I guess instead of
the musicians in the orchestra you would have speakers sitting in their
place - but you would still need an orchestral hall and the speakers would
still need to be in exactly the same places the musicians were sitting - Im
sure somebody must have  tried this - again not something you can listen to
in the living room.



___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound