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Discussion Starter · #1 ·
I just resurrected a Dolby ProLogic receiver after a few years in mothballs. I connected it up to a new HD cable box , tuned to a Dolby signal source on cable, and activated the digital reception on the receiver (via optical cable). The source audio lit up the Dolby Digital LED on my receiver and very nice audio came to my L/R speakers but NOTHING to the center (it was an NFL game where their play by play was 100% to the center, all I got was crowd noise).


So now I need to do some troubleshooting, the center speaker IS ok, it may be as simple as the center speaker level is turned down to zero on the receiver but I doubt it. If it is, I'm stuck because the level can ONLY be increased via a button on the remote and I have misplaced the remote



Other that the above I am assuming it could be ...


1. No signal coming from the center signal output , is there a way to test for the presence of audio on that center out terminal ? Use multimeter of something



2. Bad optical cable, is it possible for the cable to NOT pass all of the audio or it is ALL or Nothing ?


3. The cable box is not passing the center signal to the surround sound system, I would guess this is unlikely, right ?


Any ideas appreciated



Andy
 

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Andy,


First off, a clarification. You say this is a ProLogic receiver, but then later you say the Dolby Digital light comes on. Which is it? ProLogic only receivers rarely had digital inputs.


If it's a standard Dolby Digital receiver, which decodes 5.1 from the digital input (as it would seem to be based on your other comments), here are my suggestions.


Can you change the sound field/surround/listening mode on the receiver without the remote? If so, cycle through all the various modes and see if you can get output from the center channel in any of them. If no success with the cable box, try getting output from the center channel using an analog stereo input - could still be the cable box, or some other component. If you still get nothing, I would definitely start to suspect the receiver.


If you get center output in some modes but not in Dolby Digital, then I'd lean more towards the cable box. Go into the setup menu of the cable box and see what options there are for changing the digital output. Usually options will be 'off'', 'bitstream', 'pcm', etc. Try changing those and see if anything happens on the receiver - although if you have a Dolby Digital illuminated on the front panel, that would seem to indicate that the receiver is successfully receiving and decoding a DD signal. And if that's the case...


I would probably lean towards one of your thoughts, that the center channel volume is turned all the way down (though why anyone would do this and leave it active, I have no idea). Or, it could simply be that the center channel amplifier is not presently functional.


Good luck!
 

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check your center channel settings in the speaker setup from the front panel
 

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Have you tried say....a DVD? A football game broadcast in DD is not the best way to see what sounds are coming from certain speakers.


And just fyi, DD is not necessarily 5.1.
 

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Discussion Starter · #5 ·

Quote:
Originally Posted by Aaron Gilbert /forum/post/15469083


Andy,


First off, a clarification. You say this is a ProLogic receiver, but then later you say the Dolby Digital light comes on. Which is it? ProLogic only receivers rarely had digital inputs.


I

Thanks for the feedback folks, it has been so long since I really new this receiver that I had to think about the above question.


The answer is...

"#

# 6.1-channel surround sound with Dolby Digital, DTS ES, and DTS 96/24 decoders and Dolby Pro Logic II support with 6 discrete inputs "



As suggested, I tried again with a non-football station, tested it on The Tonight Show and David Letterman and also a HBO movie in HD. Using an optical cable from the cable box to the digital input of the unit. On all all channels EXCEPT the tonight show, the receiver's digital indicator is lit and it shows icons that a source is being sent to Center, front L/R speakers, rear L/R speakers (not hooked up yet) and sub-woofer. For some reason last night the Tonight Show was only lighting up the icons for front L/R , perhaps NBC was not sending surround sound last night.


Anyway, on the two stations that got all speaker icons displayed, I received audio to front L/R and sub-woofer but nothing to the center. The HBO movie must of been sending all dialog to the center and occasionally the left/right fronts would play brief incidental music.


I played with every DSP setting, pressed every button I could thing of, never anything from the Center. I will try a second optical cable tonight and triple check speaker wires. After that, it has to be the center speaker levels , right?


I do not have a DVD player that has digital outputs, so can't check with a DVD.
 
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