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Optical digital output level difference SD and HD channels

Teacher

Optical digital output level difference SD and HD channels

Just got a Zvox sound bar and hooked the Uverse box to it using the optical digital output.  It works great except for a marked difference in sound levels between SD channels and HD channels.  At least 6db's.  Tried customer support chat but I swear the guy never really understood what I was trying to tell them.  He finally said it was a problem with the Zvox and contact them.  The Zvox works fine for everything connected to in including an audio reciever going into an analog input.  It doesn't control the input level from the Uverse box.  Even the same provider such as channel 5 and channel 1005 have this marked difference in volume level.

 

Anyone had this or know of a way to equalize the volume levels?

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‎09-30-2015 1:39 AM

Re: Optical digital output level difference SD and HD channels

OK figured it out.  The Uverse box was set to surround sound.  The Zvox is a 2.1 box and while the surround sounded good on it from the HD that was limited the SD volume.  Set it to stereo and levels are matched now.

 

Too bad tech support online did not know this or offer as a solution saying it was a problem with the Zvox even though I discounted that.

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‎09-30-2015 1:39 AM

Re: Optical digital output level difference SD and HD channels

stinger22 - Here is a wild guess offered in the spirit of check everything -
Zvox is not a surround decoder?? It is virtual surround. Is that correct?
SD channels do not have surround sound. HD channel do.
Most TVs do not have a surround decoder & have no sound on HD when U-verse is set to surround.
I have a fairly new Toshiba TV & for some strange reason set the U_verse sound to surround & it was much louder than stereo on the Toshiba.
I am proposing that you, also, have set the U-verse sound to surround & the ZVOX is acting like my Toshiba.
If you set the U-verse sound to stereo, you should be OK.
This theory is based on ZVOX being virtual surround, instead of a decoder. If I have that right.
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Teacher

Re: Optical digital output level difference SD and HD channels

Yes see my second post.

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Re: Optical digital output level difference SD and HD channels

stinger22 - Yes, I saw it later. Sounds familiar. Often happens - another post while composing.
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Re: Optical digital output level difference SD and HD channels

The problem is that Uverse is setting the "Dialog Level" or "Dialnorm" parameter incorrectly in the digital audio stream on the SD channels.  Some receivers use that Dolby metadata parameter the way it was intended -- to automatically adjust the relative volume between channels.  When Uverse sets that parameter incorrectly in the digital output to the receiver, the receiver is compensating incorrectly and screws up the audio level completely.  The Uverse decoder box apparently ignores that parameter and the analog output from the STB for those channels seems to be OK.  The only workaround is to use the analog outputs from the STB.  The real fix is for Uverse to set up their encoding equipment correctly and use a reasonable dialnorm setting for all channels.

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