# What is RF Mode versus Line Mode



## badwilly

Hi

This is probably a stupid question. In the Dolby setup screen, it lists "RF Mode" or "Line Mode". 
What is the difference?

:nono2:


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## Mark Lamutt

Technically I have no idea. I have mine set to RF mode because the output volume is louder.

Welcome to DBSTalk! :hi:


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## badwilly

Thanks. I switched from RF to Line and the volume accross channels seems a little better. However, I still notice that if I go from CNN to a HD channel with dolby digital, I always need to up the volume. I wish there was a smart volume control or similar option like my TV has.



Mark Lamutt said:


> Technically I have no idea. I have mine set to RF mode because the output volume is louder.
> 
> Welcome to DBSTalk! :hi:


:eek2:


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## Ddavis

RF mode stops DD5.1. Only stereo in RF mode. Line mode gives you DD5.1 over optical.


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## badwilly

Hi. I'm confused now. I have a Denon 4306 and regardless if I choose Line or RF mode, it shows a 5.1 signal coming in from the optical cable. It switches to 2 channel when I move from a HD channel to say CNN.



Ddavis said:


> RF mode stops DD5.1. Only stereo in RF mode. Line mode gives you DD5.1 over optical.


:eek2:


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## David_Levin

RF vs Line only affects the Analog outs (Line out for sure - probably RF as well).

It controls how Dolby Digital 5.1 is downmixed.

RF: Down mixed to Right/Left Stereo
Line: Down mixed to Pro-Logic Surround.


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## badwilly

Thank you. Now that makes sense. I'll keep it on line mode because I do send a analog signal to a pioneer stand alone DVR. If I understand you correctly, I'll get my prologic on the standalone when I record from the VIP622



David_Levin said:


> RF vs Line only affects the Analog outs (Line out for sure - probably RF as well).
> 
> It controls how Dolby Digital 5.1 is downmixed.
> 
> RF: Down mixed to Right/Left Stereo
> Line: Down mixed to Pro-Logic Surround.


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## Mark Lamutt

David_Levin said:


> RF vs Line only affects the Analog outs (Line out for sure - probably RF as well).
> 
> It controls how Dolby Digital 5.1 is downmixed.
> 
> RF: Down mixed to Right/Left Stereo
> Line: Down mixed to Pro-Logic Surround.


Thanks David! I had no idea that's the way it worked!


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## David_Levin

Hmmm, the manual only mention "Dynamic Range":

Line Mode. When you use this setting, in comparison to RF Mode, the dynamic range is wider, which makes the music and loud noises louder, but voices quieter.

RF Mode. When you use this setting, in comparison with Line Mode, the dynamic
range is narrower, which makes music and loud noises quieter, but voices louder.

The wide dynamic range might be needed for Dolby Pro Logic. I tried it when I was setting up my DVD Recorder. RF mode lost all the surround sound.

My recollection of the help screen is different. Anyone sitting in front of thier machine? You'll need to hit down arrow to go to the 2nd help screen.

In any case, the names of the buttons really makes no sense.


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## Bradtothebone

RF Mode just compresses the sound (less dynamic range, or difference between the loudest and softest sounds is less). This is a good setting for watching at low volume (such as late at night when others are sleeping). Line mode should always be used for normal viewing. I agree with you, David - why in the world they chose those names is beyond me.

Brad


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## David_Levin

I still don't think this setting has any effect on 5.1 (which should be leaving the box untouched).

Now, if the source if 5.1 but you have the digital out set to PCM, then a Down Mix occurs. This setting will probably affect you there too (not that many people are probably operating this way).

For 5.1 out a reduced dynamic range "night" mode is the job of the Dolby Digital processor. The setting would be on your receiver (not the 622).


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## David_Levin

Ok, I'm looking at the "Dolby Digital Help" screen....

"Select the Line Mode button if you want to use Line mode compression and Dolby Stereo Surround."

"Select the RF Mode button if you want to use RF mode compression and standard stereo."

(Obviously, using the word your trying to define in the definition is useless, but let's move on....)

But, it does say that "Line Mode" gets you Dolby Stereo Surround, and "RF Mode" is standard stereo.

These are pretty standard options when downmixing 5.1 to stereo outputs. Probably applies to Optical PCM, RCA, & RF out.

They may call it "Dynamic Range" because the modulated stereo (TV2 RF out) doesn't have the frequency response to suport Dolby Surround Sound.


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## tnsprin

I found lots of detail on the Dolby site.

See document
http://www.dolby.com/assets/pdf/tech_library/18_Metadata.Guide.pdf

Page 10 specifically describes the two modes (LINE and RF).


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## badwilly

Hello
That was a very indepth explaination of the modes. Obviously, I will keep my unit in line mode. I still wish the VIP622 had a way of normalizing volume control however. When I switch from a channel with 5.1 to a channel that the unit outputs PCM on, the volume really gets loud. A good example will be switching from the SCIFI channel to HBOHD. Volume drops significantly when switching to the HBOHD channel. Since I haven't made 5 posts I had to delete the URL link in my reply in order to reply.



tnsprin said:


> I found lots of detail on the Dolby site.
> 
> See document
> 
> Page 10 specifically describes the two modes (LINE and RF).


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## Bradtothebone

tnsprin said:


> I found lots of detail on the Dolby site.
> 
> See document
> http://www.dolby.com/assets/pdf/tech_library/18_Metadata.Guide.pdf
> 
> Page 10 specifically describes the two modes (LINE and RF).


There is also some good info on Page 12. The most important thing to note is that the Line/RF mode ONLY affects the (downmixed) analog outputs (L/R Stereo and RF) - not the digital optical, which is passed unchanged on to the A/V receiver or TV. I wonder how it affects the HDMI output, which is currently 2.0 stereo? I may have to experiment with this tonight.

Brad


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