Channel Mapping question

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Djard
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Channel Mapping question

Post by Djard » Tue Oct 16, 2012 9:08 am

I'd like to create an audio file to test my Cambridge FPS2000 digital 4.1 surround sound system. I installed an AC3 codec and am able to play surround sound music with Media Player Classic. The rear speakers sound a bit weak, but that may be caused by the music recording.

By creating a test file with five signals in sequence ("Front left, Front right, etc.), each at the same volume, will help me check my setup.

I recorded 5 mono tracks and mapped them as follows, but no sound comes from the Sub-woofer and Rear Left speaker when I play the file.

Front Left____________Channel: 1
Front Right___________Channel: 2
LFE/Sub-Woofer Channel: 3
Rear Left_____________Channel: 4
Rear Right____________Channel: 5

I downloaded a 7.1 test file from the Internet but can't find one for a 4.1 system, so I'd like to make my own. Can anyone lend a hand and tell me what I might be overlooking?

kozikowski
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Re: Channel Mapping question

Post by kozikowski » Tue Oct 16, 2012 3:20 pm

The rear speakers sound a bit weak
Surround recordings put you in the middle of the audience, not the middle of the bassoons (as a rule).

I do wonder why no test recording I ever met tests the LFE. There has to be some reason.

Koz

steve
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Re: Channel Mapping question

Post by steve » Tue Oct 16, 2012 5:48 pm

According to Wikipedia, "standard" 5 channel audio does not have a LFE channel: http://en.wikipedia.org/wiki/Surround_s ... r_channels

What are you running the Cambridge FPS2000 from - a SoundBlaster Live?
Although the Cambridge FPS2000 manual is rather vague, it seems to imply that the SoundBlaster live should be configured for 4 channel audio, thus I would guess that the Sub output comes from low-pass filtered sum of front left and front right.
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