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Avr vs Stereo Amp Power Requirements

doublebstyle

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I am kind of new to this hoppy and really curious about something. I had a pioneer vsx 323 avr and recently switched to loxjie a30.

Vsx 323 is an avr with a lot of going on inside with DSP, hdmi board etc with a linear power sup and class ab afficiency it is rated 100watt at 6 ohm *5 channel in %0,6 thd and rated 155watt max total power consumption

Loxjie a30 has a switching power supply and class d efficiency nothing inside and around 30watt *2 channel in 6ohms around the same thd and has a 24volt 6.5 amp power supply total 155watt again

How come a complicated avr with less efficient power supply and class ab efficient can power 100watt *5 and a simple class d stereo amp can only deliver 30watt*2 with the same total power of 155watt?

Something is not matching here. If someone can explain I will be appreciated.
 

RayDunzl

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How come a complicated avr with less efficient power supply and class ab efficient can power 100watt *5 and a simple class d stereo amp can only deliver 30watt*2 with the same total power of 155watt?

The spec I see says "typical power consumption", not maximum.

1710854728756.png


"Typically", your speakers will only be drawing a watt or two, unless you're really hadbanging.

The A30:

1710855099371.png
 

DVDdoug

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A Kill-A-Watt might be a "fun" gadget! ;)

The receiver should be marked with maximum power consumption (or current) near the power connector and the power supply for the Loxjie should be similarly marked.

But the Loxjie power supply appears to be "overrated". It would be tested stand-alone and it could be capable of more wattage & current than the amplifier uses and they can't guarantee that somebody won't plug the power supply into something else. Based on the claimed efficiency of the amplifier, you probably aren't consuming anywhere near 155W (but that's the output, not the input AC power).

Vsx 323 is an avr with a lot of going on inside with DSP, hdmi board etc
That stuff doesn't take as much power. It takes power to drive speakers.

with a linear power sup
A linear power supply is least efficient at maximum power output. With little or no current "pulled" from the power supply it doesn't consume much power. But it is less efficient at maximum power compared to a switching supply, especially if it's a regulated power supply because a linear regulator "eats power" when supplying current.

Class A/B and Class D have a similar relationship with both consuming very little power at low output. (The class D output-stave may actually consume more power than class-A when idle, but there shouldn't be much difference depending on the design details.) At higher power, Class A/B wastes more energy whereas with Class D most of the energy goes to the speakers when it's putting-out power.

and class ab afficiency it is rated 100watt at 6 ohm *5 channel in %0,6 thd and rated 155watt max total power consumption
It can't put-out more power than it pulls-in! If it's putting-out 5x100W constant test-tones it has to consume more than 500W. ;)
 
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