Most of us monitor voltage.
That is NOT the same as monitoring power!
To monitor power one must instananeously read both current and voltage at the load and then multiply the two readings/measurements, the result is instantaneous power delivered to the load.
There are IC chips that do that. But, in general they do not have a big range, unless they are very complicated and thus expensive.
Even our household electricity meters only monitor current and make an assumption on the supply voltage, to allow a read out in Power units.
As far as I have read in the above replies all have fallen into the trap that an assumption on resistance has been made without realising it. They all take the drive voltage and convert that to power using the standard formula: Power = Volts squared divided by load resistance. This ignores the variation in load resistance. That inadvertent assumption leads to gross errors in power readings.
That is NOT the same as monitoring power!
To monitor power one must instananeously read both current and voltage at the load and then multiply the two readings/measurements, the result is instantaneous power delivered to the load.
There are IC chips that do that. But, in general they do not have a big range, unless they are very complicated and thus expensive.
Even our household electricity meters only monitor current and make an assumption on the supply voltage, to allow a read out in Power units.
As far as I have read in the above replies all have fallen into the trap that an assumption on resistance has been made without realising it. They all take the drive voltage and convert that to power using the standard formula: Power = Volts squared divided by load resistance. This ignores the variation in load resistance. That inadvertent assumption leads to gross errors in power readings.
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Hi,
This is why, at low frequencies, there is not much power dissipated in the voice coils.
Mutliply current and voltage and cosine of phase between both.
This is why, at low frequencies, there is not much power dissipated in the voice coils.
I am interested. Can you give some references ?
AD633JRZ
In Digi-Key search for multiplier ic
Linear - Analog Multipliers, Dividers
then select 4-quadrant
learn well
In Digi-Key search for multiplier ic
Linear - Analog Multipliers, Dividers
then select 4-quadrant
learn well
you don't need cosine.
The instantaneous power is simply the current times the voltage at that instant.
No, that does not tell you or any one else the current.
P=IV
You need both to calculate power.
Yeah, with a digital source, it isn't that hard. Actually measuring the current and voltage, or finding a fast watt-meter is best, but you can get a very good idea just from measuring a test tone.
As for dynamics, most CDs don't have as much as you might think.* A typical ratio of average to peak is 18dB. Some better CDs will have 22dB or more range . If the recorded passage is lower than that, it probably is not meant to be loud. Think about it. Quiet passages are mot meant to be at 80dB SPL.
*I've analyzed about 16000 tracks. 16dB from average to peak is typical of good pop, jazz, rock. Classical and well mastered stuff can be at about 22dB peak/average. Recent "squashed" mastering is about 10dB below peak with a good bit of clipping.
As for dynamics, most CDs don't have as much as you might think.* A typical ratio of average to peak is 18dB. Some better CDs will have 22dB or more range . If the recorded passage is lower than that, it probably is not meant to be loud. Think about it. Quiet passages are mot meant to be at 80dB SPL.
*I've analyzed about 16000 tracks. 16dB from average to peak is typical of good pop, jazz, rock. Classical and well mastered stuff can be at about 22dB peak/average. Recent "squashed" mastering is about 10dB below peak with a good bit of clipping.
All you need is a scope, the music playing and a scope
of course the knowledge how to measure is needed too.... you need speaker too🙂
It is simple and there's no tips and tricks for that.
regards,
Carlos
of course the knowledge how to measure is needed too.... you need speaker too🙂
It is simple and there's no tips and tricks for that.
regards,
Carlos
Instantaneous voltages and instantaneous currents are significant values.
Instantaneous powers are not. Electrical power needs some amount of time to show its effets.
Ah I see, that's OK then. I'm fine with +12dB peak dynamics. +34dB peaks scare the crap out of me listening less than 1 meter away from my speakers 😱
If there is anything wrong in what I wrote, that is
"Instantaneous voltages and instantaneous currents are significant values. Instantaneous powers are not. Electrical power needs some amount of time to show its effets."
or if you do not agree, please tell me and explain why.
Power is Amperes times volts.
Power does not need to be applied for a minimum time or any specific time.
Instantaneous power is defined as the power at that instant in time.
At that instant in time the power is Volts times amperes.
You don't need cosine or any other factor in there to determine the instantaneous power.
Power does not need to be applied for a minimum time or any specific time.
Instantaneous power is defined as the power at that instant in time.
At that instant in time the power is Volts times amperes.
You don't need cosine or any other factor in there to determine the instantaneous power.
I agree with you about leaving the cosine for instantaneous power.
But I wonder about the interest of knowing instantaneous electric power calculated using instantaneous values of voltage and current.
The Thread opener asked for peak power.
I use peak power when determining the operating points of semiconductors in circuit.
I also use peak power to or it's reciprocal when looking at the minimum current passing across a single ended ClassA stage.
Very many semiconductors are specified by an absolute max peak power.
There are probably many other non audio applications where peak power could be useful.
I use peak power when determining the operating points of semiconductors in circuit.
I also use peak power to or it's reciprocal when looking at the minimum current passing across a single ended ClassA stage.
Very many semiconductors are specified by an absolute max peak power.
There are probably many other non audio applications where peak power could be useful.
The asked peak power has to be converted to peak voltage to be meaningful.
I haven't seen serious specifications of peak power for semiconductors or other electronic devices without mentioning time.
Googling the term "peak power", the first hit just shows that :
http://www.google.fr/url?sa=t&rct=j...sg=AFQjCNHwCZ32S6jvTWUAC67U6MfBuz8P8Q&cad=rja
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