Anyone know anything about home audio wiring?

[Shag101]

Hi All,

I'm trying to figure something out.  

I have a hdtv, hd cable box and a receiver.  I want true 5.1 digital surround sound.  
I have an HDMI cable going from the out of the hd cable box to the in on my TV.  I then have an optical cable going from the out of the tv to the optical in on the receiver.  My receiver says Pro Logic (PCM).  
If I move the optical cable from the out of the tv to the out of the hd cable box, my receiver then says digital.  
I dont understand why it dont say digital when going from my tv.  I would think the digital signal from the HDMI would go down the optical to my receiver..
Is Pro Logic (PCM) the same as Digital?  When gong back and fourth, they both sounded pretty much the same.  When it said Pro Logic, it was louder than when it said digital.  
thanks in advance

chris

[TwilightOdyssey]

Hehe ... a subject I know a little bit about ... ;)

Go from your sources directly to the receiver. Use the HDMI for video only, not audio.

Make sure your sources are set to output BITSTREAM or DOLBY DIGITAL output for the audio, not PCM or DOLBY 2.0.

If you have any questions, you can post em here, or call me at my office (Sound By Singer), 212.924.8600.

[TwilightOdyssey]

Oh, to answer your question:

Dolby Digital and Pro Logic. Pro Logic is a decoding matrix, Dolby Digital is the carrier codec, if that makes any sense. Let me put it this way: All Pro Logic material is Dolby Digital if it's from a digital source. But not all Dolby Digital is Pro Logic.

Dolby Digital is used as short hand by some companies to signify 5.1 or 7.1 discrete digital channels of audio.

[Shag101]

Thanks Ben,

I will move the optical cable from the out on my tv to the out on my cable box and keep the other end in the IN on the reciever.  
My recevier will say Digital once I do this.  Currently is says Pro Logic (PCM).  
Last night I was going back and fourth with the optical cable and I really cant tell the difference between the two.  The Pro Logic was louder then when it said digital.  Is that normal?  Maybe I just wasnt listening well enuff.  thanks

[TwilightOdyssey]

Pro Logic will probably be louder because it is essentially a stereo signal which is going through an analog matrix.

[Shag101]

Cool, thanks again Ben!

One last question.  I dont have many optical IN's on my receiver.  Actually I only got 2..lol
Its a 4 year old sony..but still does the job.

Anyway, I bought a 3 way optical switch off amazon yesterday.  Would you know if they work like they say and dont degrade the signal.  thanks

[TwilightOdyssey]

Get this unit: The AUDIO AUTHORITY 1154A. It will do what you want it to, does auto switching, and is lossless. www.audioauthority.com, look under Residential, and then under Switchers. :)

[Shag101]

Ok, I have another question...lol

I bought a monster ultra 600 hdmi cable for $99.  
My friend bought a dvd/vhs thing and it came with a free one in the box.  
He does not need it.  

Crutchfield sent me a mag and they had an article that HDMI is HDMI.  It has to be good or you get no signal.  In other words, I dont need a $99 cable.  I should get the same picture as a cheap one.  

Would you know if this is true.  Cuz if it is, i will return the monster cable and take his for free.  thanks