In the sussurous long grass OR the return of surround sound
 

Serge Auckland wrote:

It's undeniably true that no hi-fi equals the live experience, although a
very few recordings come close.I think you are right that any solution will
involve an electronic implementation. You may be interested in the work
Fraunhofer IDMT and Lawo AG have done in Germany on soundfield synthesis.
They have taken a surround signal, and calculated what the soundfield needs
to be at several hundred points around the listener. At each point they have
a small active loudspeaker, driven from a several hundred channel
router/mixer. Hardly a practical domestic solution but the demos I heard at
the AES and at IBC were most impressive for giving a live feel, not only on
music but everyday urban noises. As you know, pairwise stereo only works
well for 'speakers directly in front, works after a fashion for 'speakers
directly behind, and not at all for those on the side. The Fraunhofer
soundfield synthesis gets away from the pairwise presentation.

There's some info about this on the Fraunhofer IDMT website
http://www.idmt.fraunhofer.de/eng/bu..._acoustics.htm

S.

Interesting. I in fact sometimes use side-to-side speakers for stereo,
though you would do better to think of me wearing huge electrostatic
earphones. What I do is to put an ESL63 (or a stacked pair) on either
side of my chair, so that speakers and listener form a straight line
across the narrow dimension of the room. Placement is of course
critical if you are not to suffer cancellations, but as a writer I sit
for many hours each day in the same position in front of my screen, so
it works. However, it works best in my study, where the two side walls
are not the same, one having a loft- or mansard-type angle; this may be
more important with dipoles than with box speakers. It is not quite as
good as the horn-experience of the sound climbing up your body from the
floor and walls and reaching down for you from the ceiling but, set up
right, the "big earphones" experiment can be very impressive.

Serge, if you have a moment, could you make a brief history of surround
sound, what it was, what precepts and gear it used, and why it failed
in various guises, connecting it (if it does connect) with today's
successful home AV. It just needs a few headlines for perspective for
those of us who always disdained it; we can ask if we need detail on
any part of. TIA.

Andre Jute

In the sussurous long grass OR the return of surround sound
 

"Andre Jute" wrote in message
oups.com...

Serge Auckland wrote:

It's undeniably true that no hi-fi equals the live experience, although a
very few recordings come close.I think you are right that any solution
will
involve an electronic implementation. You may be interested in the work
Fraunhofer IDMT and Lawo AG have done in Germany on soundfield synthesis.
They have taken a surround signal, and calculated what the soundfield
needs
to be at several hundred points around the listener. At each point they
have
a small active loudspeaker, driven from a several hundred channel
router/mixer. Hardly a practical domestic solution but the demos I heard
at
the AES and at IBC were most impressive for giving a live feel, not only
on
music but everyday urban noises. As you know, pairwise stereo only works
well for 'speakers directly in front, works after a fashion for 'speakers
directly behind, and not at all for those on the side. The Fraunhofer
soundfield synthesis gets away from the pairwise presentation.

There's some info about this on the Fraunhofer IDMT website
http://www.idmt.fraunhofer.de/eng/bu..._acoustics.htm

S.

Interesting. I in fact sometimes use side-to-side speakers for stereo,
though you would do better to think of me wearing huge electrostatic
earphones. What I do is to put an ESL63 (or a stacked pair) on either
side of my chair, so that speakers and listener form a straight line
across the narrow dimension of the room.

When I said side-to-side, I meant on the same side, for example, Lfront and
Lrear with you looking forward. It's almost impossible to get a phantom
image of something directly to your left. Lfront and Rfront work as a normal
stereo pair. Lrear and Rrear work as a stereo pair, but with much less
localisation, whilst Lfront & Lrear or Rfront & Rrear hardly provide any
localisation.

Your Giant Headphones should give you good localisation, albeit probably
inside your head for a central image, much like normal headphones.

Placement is of course
critical if you are not to suffer cancellations, but as a writer I sit
for many hours each day in the same position in front of my screen, so
it works. However, it works best in my study, where the two side walls
are not the same, one having a loft- or mansard-type angle; this may be
more important with dipoles than with box speakers. It is not quite as
good as the horn-experience of the sound climbing up your body from the
floor and walls and reaching down for you from the ceiling but, set up
right, the "big earphones" experiment can be very impressive.

Serge, if you have a moment, could you make a brief history of surround
sound, what it was, what precepts and gear it used, and why it failed
in various guises, connecting it (if it does connect) with today's
successful home AV. It just needs a few headlines for perspective for
those of us who always disdained it; we can ask if we need detail on
any part of. TIA.

Andre Jute

I'll do that over the next few days or so. It will be interesting revisiting
this after thirty years!

S.

In the sussurous long grass OR the return of surround sound
 

Andre Jute wrote:

Interesting. I in fact sometimes use side-to-side speakers for stereo,
though you would do better to think of me wearing huge electrostatic
earphones. What I do is to put an ESL63 (or a stacked pair) on either
side of my chair, so that speakers and listener form a straight line
across the narrow dimension of the room. Placement is of course
critical if you are not to suffer cancellations, but as a writer I sit
for many hours each day in the same position in front of my screen, so
it works.

I bet you wish you had checked the spelling of susurrous before sending
that. :-)
How did you solve your imaging problem when stacking '63s?

--
Eiron

There's something scary about stupidity made coherent - Tom Stoppard.

In the sussurous long grass OR the return of surround sound
 

Eiron wrote:
Andre Jute wrote:

Interesting. I in fact sometimes use side-to-side speakers for stereo,
though you would do better to think of me wearing huge electrostatic
earphones. What I do is to put an ESL63 (or a stacked pair) on either
side of my chair, so that speakers and listener form a straight line
across the narrow dimension of the room. Placement is of course
critical if you are not to suffer cancellations, but as a writer I sit
for many hours each day in the same position in front of my screen, so
it works.

I bet you wish you had checked the spelling of susurrous before sending
that. :-)

Nah, I know how to spell susurrous and even the alternative version of
susurrus. The much weirder thing is that as a writer I don't *need* to
be able to spell such words at all, as I am served by editors,
sub-editors, copy-editors and proofreaders all of whose job it is to
correct my spelling. Be rather anti-social to do them out of a job. In
fact, in this instance I thought two sets of rr in a headline including
susurrous and surround would look and sound a bit too Scottish, so I
changed it to see how it would look, then took a call from a fellow in
my poker school who took a bet for a hundred bucks that someone would
look up the spelling and correct me by close of business in London
tonight. You beat the bell handsomely, Eiron. Thanks for helping out.
Come again.

How did you solve your imaging problem when stacking '63s?

Quad's ESL63 is the easiest speaker in the world to stack, actually.
Stacking them for "headphone" use as described to Serge is simply a
matter of putting one behind the other. In theory their centre planes
should be 12in apart, in practice I just position the front one right
and shove the rear one right up to the foot of the front one because
the rear one is just bass reinforcement, though it also lengthens the
sweet spot. Stacking ESL63 for normal use from near the corners of a
room is the same, though you should take care that the rear one is at
least two and preferably three feet from the front wall of the room; it
is irrelevant how far it is from the sidewall and if the room is very
narrow the edge can be right up to the side wall. Stacking ESL for
in-wall use between rooms is the same: on behind the other, though the
edges of the hole in the wall should ideally be differently tapered for
a single or a stacked pair; I rarely bother with such niceties as none
of my speaker installations are permanent. Stacking ESL63 for use in a
long room, too large for one pair, is equally simple: you just make a
triangle with two '63 and the side wall of the room halfway along the
room; the centres of the two speakers should be 12in apart, so that
determines the included angle; it does no harm to have the side edges
of the '63 hard up against the wall.

Here's a rarity for you. If you have five ESL you can have absolutely
wall to wall stereo by using them as a Bessel Array. Bit expensive
because you need several amps and a largish room (Bessel Arrays are
really outdoor, public address topologies, but on the other hand too
good for the yobs who go to footie and the horses) though well worth
it. If you have such an array of dipole panels in a wall between two
rooms, they both receive the full effect but with a reversed soundstage
next door. Super-quality bass and huge linearity at all frequencies
because you will be using the speakers only on the flat part of their
power potential. Also works with larger numbers of drivers, with
progressively greater linearities because each speaker will be asked to
do less and less for a given SPL in the room...

HTH.
--
Eiron

There's something scary about stupidity made coherent - Tom Stoppard.

Good golly, I didn't know Tom read the audio newsgroups.

Andre Jute

In the sussurous long grass OR the return of surround sound
 

On Wed, 15 Feb 2006 14:15:42 +0000, Serge Auckland burbled:

snip

I'll do that over the next few days or so. It will be interesting
revisiting this after thirty years!


I have fond memories of playing with a homebuilt surround
decoder/amplifier (SQ, QS & RM) which featured 4 Sinclair Z30 power amps.
:-)

Will watch with interest....

--
Mick
(no M$ software on here... :-) )
Web: http://www.nascom.info

In the sussurous long grass OR the return of surround sound
 

mick wrote:

I have fond memories of playing with a homebuilt surround
decoder/amplifier (SQ, QS & RM) which featured 4 Sinclair Z30 power amps.
:-)

I have fond memories of regularly changing power transistors in Z30
power amps.

--
Eiron

There's something scary about stupidity made coherent - Tom Stoppard.

In the sussurous long grass OR the return of surround sound
 

In article , Serge Auckland
wrote:

"Andre Jute" wrote in message
oups.com...


Serge, if you have a moment, could you make a brief history of
surround sound, what it was, what precepts and gear it used, and why
it failed in various guises, connecting it (if it does connect) with
today's successful home AV.

I'll do that over the next few days or so. It will be interesting
revisiting this after thirty years!

By co-incidence I have just been reading an old mag with an article by
'Adrian Hope' (Barry Fox) on 'Quadraphonics'. One of the main comments
being the utter mess and confusion of having SQ / QS / CD-4 / UD-4 / etc...

Result being people going into shops asking for 'quad' records by having no
idea what 'system' they wanted. Also LPs encoded in various ways with
no-one knowing which method was used for some of them, and others having
versions in different systems. Other that were encoded, but sold as stereo.
LPs that sounded awful on the radio when reduced to stereo or mono, etc...
Must admit I sighed with relief when it didn't catch on.

Slainte,

Jim

--
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Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
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