# How do AV receivers affect picture?



## Tyrone Burton

I know what the receiver would do with audio but what does it do to the picture. They seem to do video up conversion am I right? Does that just mean it has a DVD player inside and it's up converting it, or is it actually up converting all video I watch?


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## yustr

Tyrone, welcome to TSF. We're glad you found us. :thumb:

Many modern receivers have special processing circuits that enhance video performance. So when one says it "up-converts" video to (near) HD it actually manipulates the signal. For example, it may turn a 720p analog signal into a 1080p digital. (The number refers to the number of horizontal lines - the "p" refer to whether those lines are refreshed progressively or every other one = "interlaced".)


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## Tyrone Burton

Thanks. So it's different to upscaling? Do you mean that if I connect the av receivers output to the tvs input using hdmi, and connected let's say component cables which are analogue to the AVR, the receiver would upconvert it to digital?


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## yustr

No, probably the same thing but you'll have to show us the specifics to be sure.

If your receiver has that capability - then yes, that's exactly what it will do.


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## Tyrone Burton

Cool. Don't hdtvs already have up converters in them. I have an old ps2 which is connected via component to the tvs component input. Doesnt the tv already upconvert it from analogue to digital, or does connecting a tv with component without AVR use something else. ( sorry if I'm sounding complicated)


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## yustr

Generally, a TV will take whatever signal it receives and send that to the screen without changing it. It will not add information along the way. (Whether it does this in the digial domain or analog is immaterial.) A receiver with up-converting capability uses its processors to add information not native to the incoming signal. Some TV's may have this capability too.


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## Tyrone Burton

Thanks yustr, you've been very helpful.


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## JimE

yustr said:


> Generally, a TV will take whatever signal it receives and send that to the screen without changing it. It will not add information along the way.


Partly true, however, ALL TV's (LCD / Plasma) take an input signal and convert it to the screens native resolution. The only video input that would not be altered, is a signal at the screens native resolution.

Simply because the AVR can convert an analog signal into a digital signal, does NOT mean the image will be better. Conversion quality varies greatly by the chipset used in the hardware.

So yes, the TV and newer AVR's both have the capability of upconverting or downconverting the video signal. You will need to experiment with the configuration options to see which unit handles the conversion better.


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## Tyrone Burton

Well I think that's answered it then, upconverting to digital doesn't make an image better. But I thought digital signal were better somehow than analogue? Could someone shed some light?


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## Tyrone Burton

Hdmi is supposed to be digital, isn't that better quality than analogue?


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## JimE

Upconverting/downconverting is basically just a way of altering the image resolution. It does not increase the image quality. You can't take a low quality signal, upconvert (which is simply increasing the resolution), and expect the quality to get better. The image quality won't be any better than the input signal.

Digital signals have the ability to be better, but that is a by product of the hardware used.

Component (red/blue/green RCA) (analog) inputs support "HD". They can handle the bandwidth of 720P and some 1080P.

Digital (DVI/HDMI) inputs also support "HD". HDMI v1.4 cables needed to handle high bandwidth 1080P.

The benefits of digital over analog depend on all of the equipment used and the source material.

For example: DVD player to LCD TV

with component cables (analog) = DVD player (DVDs are a digital media) converts to analog > component cables > TV (digital display) converts signal from analog back to digital for display

with HDMI cable (digital) = DVD player > hdmi cable > TV << no conversion needed...digital from source material to TV.


Conversion can only decrease quality. Best case scenario, quality remains the same. So each time a conversion takes place, you have the chance of losing quality.


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## Tyrone Burton

Well I'll be hopefully getting an av receiver and I have an original xbox and ps2 which use component. I'll be putting these cables in the av receiver and the signal will pass through hdmi if you know what I mean. It will then be up converting it to digital, will it decrease quality as you said or what I'm guessing is it varies on the receiver or tv.


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## JimE

It will convert the signal from analog to digital.

Up/down converting is the process of changing the resolution and will only be done or needed, if the source resolution is different from the native resolution of the TV. If it is needed, you will need to experiment and see if the AVR or TV are better at performing the conversion. It's possible they will both perform equally well and it won't matter. Just something to keep in mind.


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## Tyrone Burton

I think I'm wrong but does that mean that a 576i resolution from analogue would be unconverted to the tvs 1080p native res?


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## JimE

Yes. 

576i = 720×576 resolution

That resolution will be (up) converted to 1920x1080 (ie: 1080P).

And again, that is NOT increasing the quality. It is just altering the resolution so that it can displayed on the TV. If it wasn't converted, it would be displayed on the TV with a huge black border on all 4 sides.


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## Tyrone Burton

And that's not upscaling?


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## JimE

Yes, it is upscaling. Increasing the resolution.


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## Tyrone Burton

Wow thanks dogg, you've been extremely helpful on this thread and the other too. Thanks


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## JimE

No problem.


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## Tyrone Burton

Id just like to ask something. If I put headphones in the headphone port on the av receiver, would that improve the sound quality of the headphones? It's just I won't be getting a surround just yet.


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## JimE

I wouldn't say "improve". And it would depend upon the devices that you are comparing.

It's a digital signal, so any difference between any amp would be the electronics processing the audio signal and converting it to analog for output. As we are talking about a low level signal (ie: headphone jack), there shouldn't be much difference between devices. 

The item that has the biggest affect on audio, in any system, are the speakers/headphones. Using the same amp as a reference, there is a night and day difference between quality speakers/headphones and low end models. Typical rule of thumb is that the speakers should account for 2/3's of your surround sound budget.


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## Tyrone Burton

Would putting the headphone jack in the tv port be better than theAVR port?


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## JimE

Best way to know would be to simply test.

TV outputs are typically average at best. Between the two, the AVR should have better sound and will have better control over the sound.


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## Tyrone Burton

Right thanks. The headphones are as I said only temporary. People have battles and opinions on different sites about this, but would you recommend a surround setup, or surround headphones. I frankly would think the main setup as I think their cramping more stereos in tiny speakers.


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## JimE

Depends on how you generally watch TV or the environment. While there are some great surround headphones, I prefer to use standard speakers. But then my viewing environment is in my home and having the sound up a bit doesn't affect anyone. If you are in a dorm or apartment building, then you have to take that into consideration. It's mostly a matter of your environment and personal preference.


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## Tyrone Burton

I think I'd opt for the speakers as they are more supported by the AVR more so than the headphones, and also its hard to find headphones that support DTS HDmaster audio 7.1, there almost all Dolby digital 5.1.


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## JimE

A few things to note. 

Most headphones are stereo. The headphone connector on the front of an AVR is a stereo port. The decent surround headphones that I've used have been for the PC and were USB.

ALL of the audio formats (ie: DD5.1, DTS, DTS-ES, Dolby Digital EX, Dolby TrueHD and DTS-HD™) need to be decoded. So support is based upon the decoder (typically the AVR), NOT the speakers or headphones.


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## Tyrone Burton

So if a headphone product says it supports DD5.1 does that mean if I put it through an AVR, it will send out the signal to them?


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## JimE

I can't say that I've seen that noted on any headphones.

In any case, as noted previously, headphones don't/can't decode a digital audio stream. But again, it depends on the type of headphones (ie: how they connect). Any headphones that connect via a 3.5mm or 1/8th jack, are connected to an analog port and cannot decode a digital audio stream.


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## Tyrone Burton

Right then, it must mean that they come with some sort of decoder. I bought some headphones which I still use today which supported dolby digital. I'm unsure now if it was Dolby pro logic or DD 5.1, but it came with a decoder which was a USB conection, the decoder had a port for the jack but I didn't know the headphones were only for a pc.


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## JimE

In that case, yes, it could have the ability as the signal would be passed digitally through USB. And as they are USB based headphones, they are PC/game console headphones.


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## Tyrone Burton

Can a audio format like DD be passed through headphones through a normal jack, or is this fatter jacks that are only supported.


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## JimE

No. "Normal" jacks are analog.


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## Tyrone Burton

And USB is digital? Hens forth why DD can be passed through


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## JimE

Correct.


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## Tyrone Burton

Cool, you've covered not one thing, but two in this thread. This will certainly help other people out too, thanks.


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