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I am still trying to learn about AVRs and Amps as much as possible so this might be a stupid question. If an AVR is rated at 700W, 100 per channel, what happens if you only use 4 of the channels. Does the extra unused power get redirected into the channels that are being used?
 

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I am still trying to learn about AVRs and Amps as much as possible so this might be a stupid question. If an AVR is rated at 700W, 100 per channel, what happens if you only use 4 of the channels. Does the extra unused power get redirected into the channels that are being used?
Your SR5012 is rated 100W/Ch into 2CH at 8-ohm ... roughly 80% of that or 80W/Ch into 5CH and roughly 65W/Ch into a 7CH setup.
 

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Your SR5012 is rated 100W/Ch into 2CH at 8-ohm ... roughly 80% of that or 80W/Ch into 5CH and roughly 65W/Ch into a 7CH setup.
My question was overall not specifically about m y AVR. However, based on what you are telling me, I should assume I am getting only 80% of what is advertised for the first 5 channels. My original question, does power get redirected from used channels to the ones that are being used?
 

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Your SR5012 is rated 100W/Ch into 2CH at 8-ohm ... roughly 80% of that or 80W/Ch into 5CH and roughly 65W/Ch into a 7CH setup.
My question was overall not specifically about m y AVR. However, based on what you are telling me, I should assume I am getting only 80% of what is advertised for the first 5 channels. My original question, does power get redirected from used channels to the ones that are being used?
Now I’m only using logical thinking here

But going by what JD said that you get more wattage if you’re using 2 channels than 5 channels, and get more wattage with than 7 channels then logical thinking would lead me to believe that... yea? The AVR is able to deliver more wattage with less channels being utilized

Now if the power gets “redirected” from the unused amps to the ones being used... that I don’t know the method by which things happen but either way you still get more power with less channels used right?
 

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I am still trying to learn about AVRs and Amps as much as possible so this might be a stupid question. If an AVR is rated at 700W, 100 per channel, what happens if you only use 4 of the channels. Does the extra unused power get redirected into the channels that are being used?
There is nothing stupid about any question.
So I'd broadly divide the audio rack equipment in to AVR and amplifiers and I'm glad you know the difference.
Since AVR is doing a lot of things avr is generally given a power rating with 2 channel driven and either a frequency or a frequency range. So that is the power when it's driving 2 speakers (only). When you add more speakers the overall power reduces. This has led me to never read about avr for power ratings. To pick up my gear I research and walk into a store and get them to run as many speakers of the type I can find and hook them to the receiver I want and play them at higher than usual volume I'd be listening to.
In amplifiers, it's still old school. The watt per channel is generally given for individual channel itself.
Now coming to the main question of power distribution, I guess it's upto manufacturers and individual models. While it's definitely possible to redirect the unused channel powers to the used amplifiers in AVR, it'd be very complicated.

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My question was overall not specifically about m y AVR. However, based on what you are telling me, I should assume I am getting only 80% of what is advertised for the first 5 channels. My original question, does power get redirected from used channels to the ones that are being used?
There is only one power supply. The marketing numbers provided by mfr's are generally only into 2CH. As you add more speakers, there is less power to go around for each speaker.
 

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...this might be a stupid question...
Absolutely not, it's a very logical question.
Here's how almost all amplifiers work:
- Voltage (electric pressure) comes in from a source like CD player. The amplifier (let us say it is ONE channel for the moment) amplifies the voltage bigger, up to a limit called the voltage rails.
- The amplifier power supply attempts to flow enough electric current to sustain that voltage.
- AVRs in particular due to size and cost have limited power supplies. When the volume is cranked up, the speakers demand more current to supply that volume level.
- More channels demand even more current. Each channel individually tries to deliver the power according to the voltage.*
- Amps are tested with resistors due to time and cost. But speakers are NOT resistors and demand even more current sometimes.
- When the power supply runs out of current, the signal clips (distorts). So every single AVR delivers less power per channel as more channels are driven.*

*so the answer to your question is that if a receiver is supposedly 7x100 watts, no, you don't get 350 watts per speaker if only 2 are connected. Those channels will try to deliver 100 watts. That's the most each of those amps can deliver, maybe less if the speaker impedance is difficult. With 7 speakers connected, the power supply in an AVR cannot keep up, and might clip at 80 or 70 or even 50 watts in each channel. Unused channels help the remaining channels meet rated power, but you don't get "extra."

Fortunately, receivers generally have enough power to drive typical speakers pretty loud. Here (perhaps with some repetition) are "Head_Unit’s Rules Of Protection":
1) If when things start to sound distorted or odd you TURN IT DOWN, you are unlikely to ever break anything.
2) If you constantly "turn it up to 11" you will break something.
3) The amp and speaker power ratings do not matter. Don’t bother “matching” the amp and speaker power. That is a seemingly sensible yet actually meaningless exercise, because:
- Speaker specifications are 92% useless (and I say that as a loudspeaker engineer).
- Specs for amps are not thorough since they are measured into resistors for pragmatic reasons and speakers are not resistors at all.
4) Amps' 4 ohm or even 2 ohm rating is the most meaningful even if your speakers are 8 ohms. Should be 20-20k Hz, distortion under 1% or it's baloney.
5) For amps "more" power means (IF specs are comparable) at least three times as much due to the logarithmic nature of hearing.
6) You are less likely to damage speakers with a big amp, since let’s face it everyone cranks it up sometime, and a small cheap amp is then more likely to clip and possibly put out DC and ultrasonics (This assumes the speakers are not tiny little pieces of poop).
Now as far as if your amp is big enough, that is another matter. How loud do you want to play (with clean sound)? What speakers do you have? Is there a sub? Describe the room and what it connects to. Because you can definitely have too small an amp if you have inefficient speakers in a big space and you want to play loud.
 

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@head_unit pretty much nailed it -- summary: the receiver's power supply sets the global limit while the individual channels' amplifiers each have their own limit. You can exceed neither without clipping / distorting or eventually overheating / destroying the circuitry.

So, no, power does not get "redirected". There is just a limit to the total amount of power available on tap. From that limit, each channel can only consume so much. How much it consumes depends on the program material and volume (input voltage) and speaker impedance (highly dynamic as speakers are reactive components).
 

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@head_unit pretty much nailed it -- summary: the receiver's power supply sets the global limit while the individual channels' amplifiers each have their own limit. You can exceed neither without clipping / distorting or eventually overheating / destroying the circuitry.

So, no, power does not get "redirected". There is just a limit to the total amount of power available on tap. From that limit, each channel can only consume so much. How much it consumes depends on the program material and volume (input voltage) and speaker impedance (highly dynamic as speakers are reactive components).
I doubt that you get clipping/distortion when the demand on the power supply is more than it can deliver. If you drive all channels on a receiver at the maximum signal level, won't you just get reduced power from each channel? Undistorted?
 

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I doubt that you get clipping/distortion when the demand on the power supply is more than it can deliver. If you drive all channels on a receiver at the maximum signal level, won't you just get reduced power from each channel? Undistorted?
Honestly, I don't know for sure. I mean, if the amplifier is "asking" for current that can't be delivered what happens? I suppose at the absolute worst case something lets out the ghost.
 

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Honestly, I don't know for sure. I mean, if the amplifier is "asking" for current that can't be delivered what happens? I suppose at the absolute worst case something lets out the ghost.
I think it would manifest as a voltage droop to the amps. Power (or voltage or current) doesn't act like an incompressible fluid (e. g., water). No clipping, just less output.

Think of a Class G or H amp. There, the voltage to each amp's output is controlled by a switching mode source. I guess that it's supposed to combine the advantages of a Class A/B amp with the efficiency of a Class D amp.
 

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I doubt that you get clipping/distortion when the demand on the power supply is more than it can deliver. If you drive all channels on a receiver at the maximum signal level, won't you just get reduced power from each channel? Undistorted?
Actually, clipping is exactly that.

The amplitude of the voltage applied to the output stage of the amplifier has increased beyond the voltage/current limit of the supply rails.

The top and bottom of the sine wave are cut off or clipped and the sine wave becomes a square wave.

An amplifier makes a larger copy of the input signal. An amplifier is said to be overdriven or clip when it's required to produce an output signal greater than the supply rails can deliver.
 

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Honestly, I don't know for sure. I mean, if the amplifier is "asking" for current that can't be delivered what happens? I suppose at the absolute worst case something lets out the ghost.
It clips.

The ±V signal on both its positive and negative excursions reaches the supply rails limit and can't increase any more. It will try to stay at the maximum rail voltage or overdrive until the next opposite-polarity excursion or until the input amplitude is reduced.
 

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It clips.



The ±V signal on both its positive and negative excursions reaches the supply rails limit and can't increase any more. It will try to stay at the maximum rail voltage or overdrive until the next opposite-polarity excursion or until the input amplitude is reduced.
Also excessive heating and probably a fail safe shutdown.

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