Two dumb but important questions


Standard Member
This may be a dumb question but… why does the all the video circuitry have to go through the receiver. I understand these high frequencies are not good for the audio side. Does the receiver actually do anything with the data or is it just to interconnect other devices.

Second dumb question is… if DVDs are 5.1 what is the point of 7.1. If 7.1 comes out on DVD what will happen to 5.1 receivers. How does the decoding then work in both scenarios. Won’t the decoding get confused.


Prominent Member

You don't have to connect via the amp. If you have more sources than inputs on your display you can use the amp as a switch. Otherwise connect direct.

a couple of amps, eg Denon 3803, upconvert s-video to component, but mostly they just act as switches.

The video stuff can affect audio, hence the option on many amps to isolate the video circuitry if you're just listening to music.

Q2 I'll leave to the experts.


Prominent Member
As above, video switching is purely for convenience.

DVDs can be encoded in several channel formats. 5.1 is the "standard" surround format.

6.1 is now being introduced on some DVDs, it includes an additional rear surround channel and can be decoded by newer receivers. A 5.1 receiver will either ignore the 6th channel or matrix into the two rear speakers depending on the processing format being used.

7.1 discrete doesn't exist (yet). 7.1 receivers use the 6th channel mentioned above but send an identical signal to 2 centre rear speakers rather than just the one.

I hope that makes sense, some high-end equipment can decode a surround signal to incorporate a 7th "height" channel though but that's a different story ;)


Standard Member
Thanks for answers.

Okay, so any models that upconvert are a bit of bad idea because they have circuitry.

Presumably better to just have component input or connect direct.

On the decoding stuff I'm mistified why anyone wants 8 speakers if their living (my wife would kill me). The surrounds often have to be so small they sound tinny. I think it's all about getting us to spend me and more. The amps get hot, need fans (that break down or are noisy one day), use lots of electricity (1kw on some h/k stuff|) and end result ruins stereo.

I may just stick with 5.1, I can have larger rears and get a richer sound anyway.


Prominent Member
It all depends what you want from your system. Mine's 5.1 because I can't afford a new amp and havn't got room for the additional speakers anyway. In small rooms the 6th channel doesn't make much difference anyway.

I think opinion on the forums is that video switching doesn't make a noticeable difference but a direct connection must be technically better.

Everyone's HC is usually a compromise between funds, WAF, necessity and getting the best for the money! Cheap small speakers will sound "tinny" but as with everything this improves with financial outlay, the same applies to AV electronics which become better with stereo up the ranges.

Lots of electricity can only be a good thing though, it means there's lots of power on tap :devil:


Standard Member
Don't agree. It means more heat and more likely components will wear out. Certainly fans break down much sooner than the components inside, as I've found out over the years in computers.

Also, some manufacturers are better at it than others in power consumption. H/K are clearly the worst. But then again electricity in the US is a 1/3 of the price over here.


Prominent Member
Computer components are a different story altogether.

The high power consumption you refer to in hifi is due to the power amplification. H/K are renowned for having very high quality output stages that can provide loads of current and can drive very difficult loads. Nad are another example.

Check the power consumption of a company's preamp against their power amps.

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