# 5.1 issue with optical



## dougc (Dec 19, 2009)

I finally wired the rears for 5.1 in my HT. I have an old Nakamichi AV receivier that uses optical for digital input. When I followed the directions when using it yesterday, I don't notice any "surround" sound from the rears, just diminished sound - the same as the fronts. We watched "Armored" on Red Box (wow, what a bad movie) which I assume has tracks for at least 5.1. I have the front speakers connected to "front", rears to the "rears", sub on a pre-out, and no center. All speaker channels are set on except for center since I don't have one yet. The receiver shows a digital input is found as optical through my DVD setting, which I have selected. 

Any thoughts of what the deal is here? Did I miss something?


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## Tonto (Jun 30, 2007)

Probably not, a lot of these low budget movies are 2.1 & without the actual box (not the redbox case) you wont know. Does the reciever/DVD player tell you what is being decoded on the faceplate? You can also put in a disk that you know is 5.1 & see if you get sound. You should be able to choose between large or small for your speakers. If you are not using a sub, set them to large (this setting passes full range sound to the speaker, you don't need this with a sub). Also, are you sure you are using a fiber optic digital cable (not the 3 prong cable that came with the DVD player)?


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## whines (Oct 2, 2007)

You may need to go through the setup for your reciver to tell it that you added the rear speakers.


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## eugovector (Sep 4, 2006)

Doug, did you post this message yesterday? I think it may have been deleted in the upgrade of the forum software.

As I said yesterday, make sure that if you have "surround" and "rear" that you're using the "surround" speaker outputs. Then, use the THX optimizer on a THX disc like Pirates of the Caribbean to send pink noise to each of your speakers individually. This will confirm that you have everything hooked up properly. Then, use an SPL meter to set the levels of each.

Tell us what you find out.


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## Dale Rasco (Apr 11, 2009)

Hi Doug, can you list a model number for your receiver?


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## dougc (Dec 19, 2009)

Thanks guys, I will try another disk along with the other suggestions when I get home and then report back. It is the Nakamichi AV-8


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