[mythtv] Channel ordering wrong in 5.1 (at least for me)
Ed W
lists at wildgooses.com
Mon Apr 5 14:01:03 UTC 2010
On 04/04/2010 17:32, Jeppe Nejsum Madsen wrote:
> Jean-Yves Avenard<jyavenard at gmail.com> writes:
>
>
> [...]
>
>
>>> - Specialist audio filters. eg I use Brutefir which allows me to apply very
>>> long FIR filters to the audio in near realtime. It takes a bunch of very
>>> clever maths, but basically I can measure the parameters of my audio system
>>> and then apply a correction to fix some of the measured deficiencies. This
>>> allows you to get a very high quality audio system and for example apply
>>> speaker crossovers digitally. I use DRC to help me calculate global system
>>> corrections, this is then output directly to a bunch of power amplifiers
>>> which are hooked up to a bunch of big speakers
>>>
>>
>> correction and high quality audio in the same sentence ? :)
>>
> While it does sounds anti hi-fi, I think what Ed is describing is what
> is being performed in various high end amps such as the Lyngdorf
> Millenium (starting price around £10000)
>
>
You can get Tact/Lyngdorf stuff for a bit less than that, but actually
what they do is quite a lot less advanced than DRC will achieve.
Basically most people such as Tact/Lyngdorf/Meridian/Audessey just try
and correct minimum phase sound (ie roughly the direct audio which
reaches you). DRC (and Acourate) will compute correction filters which
actually try and "fix" the room itself - for sure there is a huge
tradeoff here that the more you correct the room, the narrower the
sweetspot, but certainly it is possible to improve things considerably
without needing your head stuck in a vice
My setup is described a little here (it's quite some years old, needs
updating, but gives you an idea):
http://www.duffroomcorrection.com/wiki/User:Ed_Wildgoose
I'm quite pleased with the IB Subwoofers under the floor. Visually
pretty subtle and they run the bass down to well under 10Hz (you can
only hear down to 20Hz, so it takes you well into the range of
explosions that you feel, eg many recent DVD releases have explosions
hitting 8Hz or lower)
I think the point is that the hifi shops are selling you what you want
to buy, but not necessarily the best system for reproducing audio (for a
given price). Also everyone seems to overlook that the room itself,
followed usually by the speakers are by far the weakest link in the
chain (and instead spend a ton of dosh on stuff like fancy cables...).
An excellent room and speakers are required for excellent sound
reproduction, but DRC can *partially* correct a non excellent
room/speakers using only clever mathematics - it's imperfect, but it
will dramatically improve whatever you have actually got (even if it's
the Abbey Rd studio)
Anyway, well off topic, but feel free to drop me a line offlist or join
the DRC mailing list if you would like to build a super-surround system
on a budget which will blow the socks off your £10-20K shop system...
Good luck
Ed W
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