power rating?

[dvdwatcher]

I still don't understand how to tell the power rating of a receiver? I'm not talking Peak Momentary Power Output that measures a very short burst of power, I'm talking continuous power. I want to make sure the receiver I get next will fulfill all my needs now and future without a separate Amp upgrade.

Also in particular the Elite's, Ive read some complaints that the lower end model VSX-1019AH-K uses a different processor or something whats this all about?

[Steve]

Keep in mind that many power ratings are over inflated on the spec sheets. What you want to look for is power labeled as RMS (I don't know what it stands for) or continuous. Don't pay any attention to Peak ratings (you already know that). You basically want it to say something like this:

140W x 7 (20Hz - 20kHz, .09% THD @ 8 ohms, All Channels Driven)

This is from the Pioneer Elite SC-25 specs. You want it to give you all this information. You want it to give the power rating with all channels driven, the THD, the impedance of the speakers, and the frequency range. Some receivers will say something like this:

90 W + 90 W (8 ohms, 20 Hz–20 kHz 0.08%, 2 channels driven, FTC)

This is from the Onkyo TX-SR607 specs. Notice it only gives the power output with 2 channels driven. Onkyo doesn't publish the power output with all channels driven for this model (at least not to my knowledge), and I seriously doubt it gets 90 watts per channel with all channels driven.

Remember, though, that even with all the appropriate information given like in the first example, there's still no guarantee that particular receiver really pushes that much power. We know the Pioneers really do because they've been tested by third parties, but with other models we're not so lucky.

[richteer]

Originally Posted by fireman325

Keep in mind that many power ratings are over inflated on the spec sheets. What you want to look for is power labeled as RMS (I don't know what it stands for) or continuous.

RMS = Root Mean Squared. And I agree that RMS watt per channel, all channels driven (preferably normalised into 8 Ohms) is the only meaningful power rating. Anything else is just marketing bull.

[Johnny Vinyl]

Originally Posted by richteer

RMS = Root Mean Squared. And I agree that RMS watt per channel, all channels driven (preferably normalised into 8 Ohms) is the only meaningful power rating. Anything else is just marketing bull.

Yep!

John

[arrt vandelay]

if you have relatively efficient speakers(~90db, 8ohm impedence), you probably will never have any issues with not having enough power w/ any of the mid-range receiver offerings from all the big names...onkyo, yamaha, pioneer, denon, etc...

if you visit this forum daily, you probably will not be satisfied with what you have and will endlessly search for something better, but that's part of the fun...

[dvdwatcher]

Originally Posted by arrt vandelay

if you have relatively efficient speakers(~90db, 8ohm impedence), you probably will never have any issues with not having enough power w/ any of the mid-range receiver offerings from all the big names...onkyo, yamaha, pioneer, denon, etc...

if you visit this forum daily, you probably will not be satisfied with what you have and will endlessly search for something better, but that's part of the fun...

Well...I dont have much yet, Ive been doing my window and question shoppinh here for about a month. As of now my shopping list consists of Polk 70',CS2,and either FXI's or Klipsch Synergy S-2. Im also leaning towards the Pioneer VSX-1019AH-K.

[Steve]

Originally Posted by richteer

RMS = Root Mean Squared. And I agree that RMS watt per channel, all channels driven (preferably normalised into 8 Ohms) is the only meaningful power rating. Anything else is just marketing bull.

Thanks. I've always wondered what that stood for.

[browndk26]

Originally Posted by dvdwatcher

I still don't understand how to tell the power rating of a receiver? I'm not talking Peak Momentary Power Output that measures a very short burst of power, I'm talking continuous power. I want to make sure the receiver I get next will fulfill all my needs now and future without a separate Amp upgrade.

Also in particular the Elite's, Ive read some complaints that the lower end model VSX-1019AH-K uses a different processor or something whats this all about?

The VSX line is different from the Elites. VSX is a lower performance line of AVR's. If I had the money I would buy an Elite AVR.

[dvdwatcher]

Originally Posted by browndk26

The VSX line is different from the Elites. VSX is a lower performance line of AVR's. If I had the money I would buy an Elite AVR.

What is the VSX for and how do you tell?

[SeanMF]

Originally Posted by dvdwatcher

What is the VSX for and how do you tell?

There is currently 6 current model Pioneer receivers that are vsx (519,819,919,1019...these aren't elite). The 2 elite vsx receivers are the vsx-21 & 23. I believe the more efficient Pioneer receivers are the ones with the ice amps..those are the sc25/27/09.

[Zman2k2]

VSX is just the model line. Kind of like buying a car. You can say you bought a Civic, or you can say you bought a Civic Si-R. Just indicates the model line.

One word of advice from a recent review of the VSX-1019. It's from Home Theater Magazine. Overall, they give the Pioneer a favorable review, and even call it a top pick. But this is what they find for power output of the receiver.

Five channels driven continuously into 8-ohm loads:
0.1% distortion at 28.7 watts
1% distortion at 34.3 watts

The whole review can be found at this link. I'm not discouraging you from buying, I'm just trying to help you make an informed choice. Personally, I'm a big Pioneer fan, and have been for years.

[Fors*]

Originally Posted by john_1958

http://www.hardwarecanucks.com/forum...review-15.html

found this article on samsung led was wondering if there is any truth to it? say verses dimming led

but nice to to know led will survive http://www.hardwarecanucks.com/forum...-review-2.html being its green friendly

Ooops, I don't think you wanted to post this info about LED LCD's in this thread?

[Big Daddy]

First, there is no such thing called RMS (Root Mean Squared) power. RMS refers to voltage, but erroneously people have gotten used to using it to rate power.

Power is defined as voltage squared divided by resistance.

P = V^2 / R

Let's assume we are dealing with a battery (DC voltage) and a resistor. If we apply 40 volts to an 8 ohm resistor, the voltage will always be the same (40 volts) so the power generated will always be the same. In this example, the power is equal to:

P = 40^2 / 8 = 200 watts

As a result of this power, the resistor will heat up to a certain temperature.

Now, let's change the voltage source to a 40 volt sine wave (AC current) and apply it to the same load resistor. In this case, the voltage is not constant and oscillates between +40 volts and -40 volts and as a result, the power generated will be less than 200 watts and the resistor will not get as hot.

How much sine wave voltage (AC) peak do we need to generate the same level of power and heat in the resistor as a DC voltage source?

The AC voltage required must have a higher peak than 40 volts DC to accomplish this. As it happens, the peak voltage is equal to the DC voltage, 40 volts, times the square root of 2.

40 volts x sqrt(2) = 40 x 1.414 = 56.5 volts

Therefore, for a sine wave (AC) voltage source, we must apply 40 volts RMS to generate the same level of power and heat in the resistor.

In the above example, the RMS voltage of a pure sine wave of 40 volts is equal to 40 volts multiplied by the inverse of the square root of 2:

40 x 1/sqrt(2) = 40 x 1/1.414 = 40 x 0.707 = 28.3 RMS volts

or

The RMS voltage of a pure sine wave is approximately equal to peak voltage x 0.707.

I hope this clarifies some misunderstandings. Remember that RMS applies to voltage, and not power.