Question about 5.1 recievers...

[mrbasic]

Hey guys,

I want to know about my Yamaha RXV-495. and, I by extension, all 5.1 recievers.

Do I need speakers connected to ALL FIVE channels to get all the unit's power into the room? (60 X 5)? I mean, are there five seperate little amplifiers in there and someone with only two speakers is missing out on 180 watts? I'm asking because I still have a little CRT TV and can hardly stand to see my quintet center channel sitting on top of it.
Buuuuut for an extra 60 watts...

Thanks guys!

 

[Nomo]

All 5 channels are driven by the same limited amount of power. The power supply and amplifier have the capability to deliver the same sum of power to whatever speakers you have connected.
By adding a center channel you will not be getting any more volume. Although a center channel is one of the most important features for an HT system. At least where movies are concerned.
The reason for adding a center and surrounds would not be for more power, but for a better overall sound immersion.

 

[mrbasic]

So, although there are 5 discrete digital surround channels encoded, they are all run through one amplfier and then split up again to be distributed to 1,2,3,4 or 5 speakers? How does the amp know if I have a given number of speakers hooked up? I know the LFE channel is seperate, but how does the rest work?

Anyone?

 

[jostenmeat]

So, although there are 5 discrete digital surround channels encoded, they are all run through one amplfier and then split up again to be distributed to 1,2,3,4 or 5 speakers? How does the amp know if I have a given number of speakers hooked up? I know the LFE channel is seperate, but how does the rest work?

Anyone?

You simply tell the receiver via settings which speakers are hooked up. This is absolutely necessary.

For instance, 5.1, tell receiver rears are not connected. Then rear channels are downmixed to side surrounds.

If 2.1, let the receiver know, and the all of your surround material will be downmixed to mains.

If 4.1 w/o center channel, you will have phantom center, where center channel is downmixed to mains.

The more channels you disengage, the more compression you may suffer. I doubt it's a big deal until you get to pretty high volumes.

 

[no. 5]

So, although there are 5 discrete digital surround channels encoded, they are all run through one amplfier and then split up again to be distributed to 1,2,3,4 or 5 speakers?

Not exactly; there is one power supply that provides the energy to the five (or however many) power amplifiers that are in the receiver. The only amplifiers that can be active are the ones connected to speakers.

5.1 surround actually has six discrete audio channels (five full range channels and one bandwidth limited channel), those channels are fed into the processor, the processor then sends each incoming audio channel to the correct amplifier (or preamp output) in the receiver.

There is a finite amount of voltage and amperage the power supply can provide to the amplifiers, and there is a finite amount of power the amplifiers can deliver to the speakers. If we assume the 60 watt per channel figure is correct, then yes, with only two speakers connected, your receiver will only produce a maximum of 120 watts. But if you have all five speakers connected, and listening in stereo, you are still "missing" 180 watts.

The thing you must understand is the equation "watts = quality" is wrong. If the amplifiers do not clip, you have enough power.

 

[Nomo]

Not exactly; there is one power supply that provides the energy to the five (or however many) power amplifiers that are in the receiver. The only amplifiers that can be active are the ones connected to speakers.

5.1 surround actually has six discrete audio channels (five full range channels and one bandwidth limited channel), those channels are fed into the processor, the processor then sends each incoming audio channel to the correct amplifier (or preamp output) in the receiver.

There is a finite amount of voltage and amperage the power supply can provide to the amplifiers, and there is a finite amount of power the amplifiers can deliver to the speakers. If we assume the 60 watt per channel figure is correct, then yes, with only two speakers connected, your receiver will only produce a maximum of 120 watts. But if you have all five speakers connected, and listening in stereo, you are still "missing" 180 watts.

The thing you must understand is the equation "watts = quality" is wrong. If the amplifiers do not clip, you have enough power.

A much better explaination than I gave.

 

[no. 5]

A much better explaination than I gave.

You made good points too.

 

[mrbasic]

Excellent! So the 6 preamplified signals remain seperate all the way to the listener's ears unless a 2.1 or 4.1 arrangement demands that they be compressed together. The little I know about amplification leads me to believe that there must be five seperate MOSFETs each producing 60 watts (in my case).
In 2.1 all 5 signals are mixed into-and driven by the two MAIN MOSFETs while the other 3 remain inactive. and so on. My center MOSFET, then has never been active in the 6 or 7 years since the unit was made! I think I'll christen it tonight! (In a good way).

You guys are great! Thanks.

PS do I close this thread, since it's answered, or what?

 

[no. 5]

Excellent! So the 6 preamplified signals remain seperate all the way to the listener's ears unless a 2.1 or 4.1 arrangement demands that they be compressed together.

Pretty much.

PS do I close this thread, since it's answered, or what?

Now that the answer has been found, the thread will take on a new life of its own, feeding on the energy of any tangent thoughts that were brought up earlier.

Only moderators can close threads.