Re: Outputting Multichannel sound from stereo sources
Re: Outputting Multichannel sound from stereo sources
- Subject: Re: Outputting Multichannel sound from stereo sources
- From: Richard Dobson <email@hidden>
- Date: Thu, 12 Aug 2010 16:04:31 +0100
On 12/08/2010 15:28, Simon Thorpe wrote:
Paul,
..
So, if anyone can point to me to a place that can sell me multichannel
recordings, I'd be grateful. But, in the meantime, I would just like to be
able to play music through more than 2 speakers. Surely, this is not so
unreasonable?
There are many such recordings avaialable for free from
www.ambisonia.com; mostly in B-Format for decoding to e.g. 5.1, some
also in DTS format 5.1 pre-decoded. Note this relies on BitTorrent; in
theory a good idea, but in practice (since hardly anyone is online to
support it) the files take FOR EVER to download.
Also worth asking on the sursound mailing list - many professional
producers and recording engineers hang out there.
But - it may not be quite as "reasonable" an idea as you may think.
What, ~exactly~, do you want/expect to come out of the extra channels?
Most people use surround to enhance auditory localization, and/or the
sense of "being there" - hence the use of the surround channels to
project the reverb one would hear from behind (and to the side etc) in a
live performance presented from a front stage; in principle, to capture
and reproduce the full "soundfield" in Ambisonic parlance. If you want
somehow to hear the music sort-of remixed with different instruments
routed to different channels, you will be pretty much out of luck. There
are techniques for demixing ("blind source separation" etc), but they
are both complex and limited. Unless really done carefully, more
speakers = worse sound, not better. Shock and awe maybe; but not
quality, clarity or refinement. You might like to consider the notion
that using more speakers simply because they are there may not in fact
give you the results you suppose. You can be confident that good stereo
is far better than bad surround!
The likelihood is, after the thrill of the novelty has subsided, that
you might actually find (especially if you set up your stereo speakers
really carefully, which most people do not bother to do) that good old
stereo both sounds really good and can be surprisingly enveloping. None
of the 5.1 and 7.1 layouts is optimally suited to good soundfield
reproduction, as those layouts are so geometrically irregular.
Conversely, a precisely laid out plain rectangular quad layout (hence,
front pair at +- 45degrees) can sound surprisingly good. Better then to
reserve your surround speakers for music expressly recorded that way in
the first place. Which inter alia takes you back to Ambisonics and the
above site.
NB this is not really directly pertinent to CoreAudio development, so is
probably OT for this list.
Richard Dobson
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden