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Discussion Starter #1
Hi guys. I need an ELI5!

How does a power amplifier that is capable of an output of 2400W RMS, only consume (from the print at the rear of the amp) 425W?

I'm going to assume Crown have not invented a free power device - what gives? I understand that a switch mode D class can be efficient; but there's clearly something more here than I understand! Does the AC supply rating (FYI I'm on 240v 50hz) only have to be an average, and sometimes it is much higher? I was under the impression this rating needed to be the maximum draw of an appliance.

Thoughts?

Paul
 

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Ok, I'm blind, where does it say that?
Where yours says 200W, mine says 425W. Which is now even more baffling... I would have thought that might line up with say the XLS1000, but it clearly says XLS2500.
There is a little white bung in mine at the voltage spec for me - 240V 50HZ. Yours are all empty.

Paul
 

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I am confused what is the question?

When pushing the amp in heavy clipping 1/3 Pink noise at 2ohms stereo the amp pulls 9.62amp according to Crown. The data can be found on the Crown's site here. Manual/Documentation> Power Draw Thermal

Not sure if this helps you or not.
 

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I guess my question might be appliance rating standards related then... as 9.6A x 230v = a potential for 2208 watts. Which sounds about right.
Our standard mains sockets are typically 10A max at our voltage.

So my question is; how is it printed at the rear to draw 425w, when it could potentially be drawing a full 2.2kw? I'm guessing there is a simple answer; like the rating is just for typical use rather than a maximum(?).
 

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I guess my question might be appliance rating standards related then... as 9.6A x 230v = a potential for 2208 watts. Which sounds about right.
Our standard mains sockets are typically 10A max at our voltage.

So my question is; how is it printed at the rear to draw 425w, when it could potentially be drawing a full 2.2kw? I'm guessing there is a simple answer; like the rating is just for typical use rather than a maximum(?).
Have you tried measuring the draw? If it puts out 2400 watts it will draw way more than 425 watts from the wall. Maybe they mean at 1 watt?
 

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Hi guys. I need an ELI5!

How does a power amplifier that is capable of an output of 2400W RMS, only consume (from the print at the rear of the amp) 425W?

I'm going to assume Crown have not invented a free power device - what gives? I understand that a switch mode D class can be efficient; but there's clearly something more here than I understand! Does the AC supply rating (FYI I'm on 240v 50hz) only have to be an average, and sometimes it is much higher? I was under the impression this rating needed to be the maximum draw of an appliance.

Thoughts?

Paul
I have the older XLS1000 that indicated 175W and I had the same question. I was curious enough to send an inquiry to Crown and the technician's response was that the rating on the back near the AC input was roughly for 1/8 power.

Crown's response:
"I know exactly what you mean. This number is a calculated number based on some regulatory testing that is required to be marked on the back of the amp. Make no mistake, this amp can and will take more than 175W from the wall when doing higher outputs. The number has to do with a specific test conditions that CSA, UL, et al require to be on power amps. For everyone else, it’s meaningless.

This amp is efficient, but it’s not > 100% efficient."
 

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I have the older XLS1000 that indicated 175W and had the same question. I was curious enough to send an inquiry to Crown and the technician's response was that the rating on the back near the AC input was roughly for 1/8 power.

Crown's response:
"I know exactly what you mean. This number is a calculated number based on some regulatory testing that is required to be marked on the back of the amp. Make no mistake, this amp can and will take more than 175W from the wall when doing higher outputs. The number has to do with a specific test conditions that CSA, UL, et al require to be on power amps. For everyone else, it’s meaningless.

This amp is efficient, but it’s not > 100% efficient."
Correct. The wattage rating on the back is power consumption at 1/8th output.
 

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Correct. The wattage rating on the back is power consumption at 1/8th output.
Which is likely to be what you will be consuming continuously.
 
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