Amplifier Wattage/power Calculation

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EasyStreet
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Amplifier Wattage/power Calculation

Post by EasyStreet »

Pardon my ignorance, but I am looking to display calculated (audio) amplifier power measurement along with the other measurements.
What is the correct method to achieve this?

Gerry
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Re: Amplifier Wattage/power Calculation

Post by Gerry »

Hi EasyStreet,

What is your reason for wanting to display the power? Is it:
  • 1/ to benefit your buying choice through personal testing?
    2/ to ensure compatibility with a specific set of speakers?
    3/ just out of curiosity?
    4/ something else?
Regards,

Gerry
Gerry
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ColdPower
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Re: Amplifier Wattage/power Calculation

Post by ColdPower »

Hi Gerry,

sorry for bringing this one up again, but I was just looking for the same answer and was surprised this one was left unanswered, as I think is a very good question.

As to why one would want to do that - I test audio amps on daily basis and my soak testing setup is with 2204A - although I'm not after most accurate results, ability to display power measurement along other measurements would be very useful.

Is it that this feature is not available, so it wasn't answered? If so, is there any workaround to achieve this?

Your answer would be greatly appreciated.
Thank you.

ColdPower
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Re: Amplifier Wattage/power Calculation

Post by ColdPower »

Okay, if Gerry is not available, anyone else from the Pico staff, please feel free to answer :D

Gerry
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Re: Amplifier Wattage/power Calculation

Post by Gerry »

Hi ColdPower,

Sorry for the delayed response, we have been very busy on our help desk, so it's only now that I'm able to clear up some outstanding posts.

The reason that the question from EasyStreet was left unanswered was because the answer would be very different depending upon what the motive behind the question was. Essentially, I was trying to establish, what type of measurement may be required and, approximately, to what accuracy and precision the power measurement was required to be (especially as there is a lack of standards, so you can do anything from a simple test to something in-line with the Audioholics Power Amplifier Measurement Standard, see here: https://www.youtube.com/watch?v=nokHMIDeVlM).

So, once again, but put more explicitly this time, exactly what test is it that you want to do, and to what accuracy and precision (you say that you are not after accurate results, but what would you expect the accuracy to be as a bare minimum)?

Regards,

Gerry
Gerry
Technical Specialist

ColdPower
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Re: Amplifier Wattage/power Calculation

Post by ColdPower »

Hello Gerry,

Thank you for taking the time to answer, I understand it's been very busy year, sorry, didn't mean to be impatient, I only saw the answer myself just now :)

So, you're generally speaking right, it's a broad topic on how amps are measured, to which standard and what accuracy, however, in this case the answer is more or less contained in the question - as the said measurement is required to be just added to the set of measurements available under the scope view, obviously the accuracy would be determined by the device used (in this case 2204A) and more specifically, the measurements it takes for the primary values that would be used - more or less same as having RMS value displayed, which likely is derived from the peak-to-peak value.

Practical example - as mentioned before, measuring audio amplifier, having the Vpp and Vrms displayed, the goal here is to be able to add a math measurement line (again with value, min, max, avarage...), that derives power over say being able to specify 4 or 8 (or whatever) ohms load, based on Vpp - pure math, nothing else, again, obviously with accuracy determined already anyway by Vpp measurement.

Would something like this be possible, seem to me would be of great help in many more than the specified example cases. If not internally possible within the software, is there a way to extract the say in this case Vpp value and do the math with external script and display externally (to the software).

Hope the above makes sense now. Your view would be greatly appreciated.

Thank you.

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