Why does my receiver have 8 speakers?

[Mik-E]

I know, I know, what a foolish question. But you may not think it a such after I explain

I have an Onkyo HT-SR800 receiver. It's a 7.1 surround receiver (obviously). The three different types of audio input are RCA, Digital Coaxal, Digital Optical. It does have an HDMI input, two in fact, but its only a video passthrough, no audio comes in. Yeah, I know, lame.

From what I've heard and read, the optical can only handle up to 6 channels. And it can handle uncompressed up to 6 as well. And that would mean it couldn't do 7.1 compressed or uncompressed, right?

If coaxal the same? If so, why in the heck does my receiver have 8 speakers? If not, that sucks. My PS3, which I run most of my best HD content, doesn't have a coaxal out!

 

[bandphan]

I know, I know, what a foolish question. But you may not think it a such after I explain

I have an Onkyo HT-SR800 receiver. It's a 7.1 surround receiver (obviously). The three different types of audio input are RCA, Digital Coaxal, Digital Optical. It does have an HDMI input, two in fact, but its only a video passthrough, no audio comes in. Yeah, I know, lame.

From what I've heard and read, the optical can only handle up to 6 channels. And it can handle uncompressed up to 6 as well. And that would mean it couldn't do 7.1 compressed or uncompressed, right?

If coaxal the same? If so, why in the heck does my receiver have 8 speakers? If not, that sucks. My PS3, which I run most of my best HD content, doesn't have a coaxal out!

What do you mean your reciever has 8 speakers?

 

[bandphan]

are speaking of the sub?

 

[majorloser]

Your receiver will support Dolby Digital (5.1), Dolby EX (7.1), DTS (5.1), DTS-ES(6.1) All of these are sent via a optical or coax digital cable.

DD, DTS and DTS-ES are all discrete signal. DD-EX uses a matrix to create the extra rear channels, similar to the system used on ProLogic to create the rear channels. DTS-ES can send 6.1 channels of discrete audio.

 

[Seth=L]

Your receiver will support Dolby Digital (5.1), Dolby EX (7.1), DTS (5.1), DTS-ES(6.1) All of these are sent via a optical or coax digital cable.

DD, DTS and DTS-ES are all discrete signal. DD-EX uses a matrix to create the extra rear channels, similar to the system used on ProLogic to create the rear channels. DTS-ES can send 6.1 channels of discrete audio.

Dolby pro logic IIx can also do 7.1 matrixed from as low as 2 channel sources.

 

[MDS]

From what I've heard and read, the optical can only handle up to 6 channels.

It can handle any number of channels as long as the data rate (bandwidth) does not exceed its capabilities. In practice that means that it can only handle DD/DTS 5.1.

And it can handle uncompressed up to 6 as well.

No. The bandwidth requirement would be way too high. 6 channels of 16 bit/44.1 kHz audio would equate to 4,233,600 bits per second (4.2 megabits per second). Higher bit depth or sampling rates would require even more.

Yes coax is the same. Both coax and optical connections use the s/pdif protocol. The only difference is one is electrical and the other is optical.

The receiver has 8 speakers because as others have mentioned you can use a matrix decoder to get 7.1. Only the newer receivers can handle 7.1 channels of uncompressed PCM over HDMI.

 

[Mik-E]

It can handle any number of channels as long as the data rate (bandwidth) does not exceed its capabilities. In practice that means that it can only handle DD/DTS 5.1.


No. The bandwidth requirement would be way too high. 6 channels of 16 bit/44.1 kHz audio would equate to 4,233,600 bits per second (4.2 megabits per second). Higher bit depth or sampling rates would require even more.

Yes coax is the same. Both coax and optical connections use the s/pdif protocol. The only difference is one is electrical and the other is optical.

The receiver has 8 speakers because as others have mentioned you can use a matrix decoder to get 7.1. Only the newer receivers can handle 7.1 channels of uncompressed PCM over HDMI.

Thank you for all of the info. All of you.

What you're telling me is what I figured. Its just very disappointing to know I have a 7.1 receiver that will never give me "true" 7.1 surround. That is correct right? No matter if compressed or uncompressed, its just too large a load for an optical or coaxal to handle.

So, I've taken another good look at my receiver and I can see where if I use Dolby Digital IIx,m it will do exactly what you guys are referring to. Also, if I use DD EX and DTS it will do the same thing. I guess I will enjoy it this way. Just wish it was 8 separate channels.