Re:Re:Re: surround looping

[a k butler <akbutler@tiscali.co.uk>]

andy said
>>a speaker to handle just the very low frequencies that a regular speaker 
>>wouldn't produce, hence the perception that it just added a bit of 
>depth, 
>>and that  it didn't matter where the sub was placed. The 0.1 in 5.1 is 
>>for one tenth of the  frequency range ....20,000/10 = 2000Hz , which 
>>makes it a regular "woofer".


matthias said
>I agree that the original idea was to have only non localizable 
>frequencies on the subwoofer, up to 120 Hz. But 2000Hz cannot be true, 
>the 
>main part of the voices would come out of the woofer under the table!
>I searched arround and it seems 250Hz is common.

that sounds more like it :-)
I knew the 2000Hz figure was nonsense, and hoped someone would know the 
right figure.
The.1 in 5.1  to represent the fraction of the bandwidth sent to the sub.
For a 250Hz x-over, it should be called 5.0125  .

In any case, most so called sub-woofers have a lowest frequency of 50Hz or 
above.





>>When Pink Floyd were using quadrophonics (1967), they had 2 sets of pa 
>>speakers,
>
>I heard the pigs show (76?) and was not impressed

Well I never made it to the '67 show, (6 years old) so I don't know how it 
actually sounded.


>>I'm all in favour of multi-channel sound, but I don't think there's 
>>anything special in the 5.1 format.
>
>true. Its quadro with a useless (for music) center speaker and a 
>subwoofer 
>which is not related to the spacialization...

I would have thought the center speaker helps a bit, as it allows a 
greater 
angle between the front L&R speakers.

andybutler