I agree as I understand average power is p = vosquared divided by Rl where vo is rms value. Now v rms is equal to vpeak times 0.707. So if we have a rms voltage 28.3 volts then vpeak is equal to vrms divided by 0.707 then vpeak is 40.02 volts. As I understand vpeak is from zero to max value for one half cycle. As I mentioned in first post as to what you bias the output to is how much of class a and how much of class AB. And I am assuming you will have two amp circuits of which you will bridge the outputs. I am also assuming the output stages can furnish the neccessary current .
All the numbers I used were peak. That is: your 24V + and- out(48V) will draw 6A through the speaker but, that is peak amps. *.707=4.242Arms. Square those rms Amps * those 8 ohms and you have 144wrms (remember peak was 288watts few posts ago). That is quite a bit of watts. 
Or you can take your peak 48Volts * .707=33.936Vrms. Square that/8= 144Wrms
Notice how after applying that square function to the parameter I forever add the rms to the end?
Or you can take your peak 48Volts * .707=33.936Vrms. Square that/8= 144Wrms
Notice how after applying that square function to the parameter I forever add the rms to the end?
the rms should not be appended to Watts.
Go back to the DC definition of Power:
P = I * V
no rms is required and neither is it ever used.
when the voltage and the current are not constant DC, one is required to average out the varying DC to get the average Power delivered/consumed.
When the voltage and the current is AC, one is required to use the rms values of current and voltage.
The rms value is the equivalent DC voltage that has exactly the same heating power as that varying voltage, not just sinewave. It can be any varying voltage even that varying DC. The rms conversion to effective heating power works for DC and varying DC and sinewave and squarewave and any other varying voltage waveform.
Power is Power.
However, I recognise that there is an instantaneous (at a single moment in time) voltage and current and that at that moment there can be an instantaneous Power value.
Go back to the DC definition of Power:
P = I * V
no rms is required and neither is it ever used.
when the voltage and the current are not constant DC, one is required to average out the varying DC to get the average Power delivered/consumed.
When the voltage and the current is AC, one is required to use the rms values of current and voltage.
The rms value is the equivalent DC voltage that has exactly the same heating power as that varying voltage, not just sinewave. It can be any varying voltage even that varying DC. The rms conversion to effective heating power works for DC and varying DC and sinewave and squarewave and any other varying voltage waveform.
Power is Power.
However, I recognise that there is an instantaneous (at a single moment in time) voltage and current and that at that moment there can be an instantaneous Power value.
Remember a ideal power amp is a constant voltage device so as the load impedance changes the voltage to the load remains the same, so for a given power output at 8 ohms will require a certine amount of current from the amp. If you lower the impedance (resistive load) to 4 ohms then the voltage remains the same but the current will change. That is how in a ideal power amp the 4 ohm power rating can double.
Is there some confusion? The power in the graphs is what you would see
with BBA-3 driving a follower output stage.
As I recall, the circuit was tested at +/- 32V, plenty adequate to deliver the
balanced 57 volts peak required to do 200 watts into 8 ohms.
It appears to me there is some confusion on audio power amps. I will attempt to explain my understanding as a part 1 then have a part 2 on Ba3 and Ba 3 balanced amps. Hopefully this generate some discussion and understanding. Please DO NOT tell me I don't know what I am talking about, while this may be true let's disuss the issue and come to agreement without flaming someone.Also I am a two finger typest so please excuse mistyping and or spelling. Part 1 For the following discussion this is a very simplified version of voltages and current, and assumes the load is pure resistive and not reactive. Voltage for audio basically a sine wave. Peak to Peak the total postive and negative swing (sine wave) around a reference point. Ideally for loud speakers no dc componet. Peak voltage The peak value either postive or negative around the reference point as above. This will be a peak voltage for 1/2 single cycle sine wave. RMS voltage is used as measure of how much work can be done by the A-C voltage. I often use peak to peak (PP) as thats what my scope displays. Current has the same values as the voltage that is peak to peak, peak and RMS. Now let's use peak voltage and peak current and convert to RMS values by the following: peak voltage = Vo, RMS voltage=Vrms, so Vrms=Vo divided by square root of 2, - peak current =Io and rms current = Irms, so Irms =Io divided by square root of 2. Average Power is equal to Vrms times Irms. Understand this is a simplified discussion of voltage and current with respect audio power amps as we are making the assumption that the load RL is resistive only and not reactive at different frequency's. This is one reason we like to have the output impeadance of the amp to be low ideally zero.There are basically two types of Audio power amps 1. Constant voltage source 2. constant current source. A constant voltage source will maintain a constant voltage for a given input dependent upon the gain of the amp into a varying resistive load.(Remember we are only talking about very simple resistive loads not reactive loads) As an example assume we have 1 volt input with a gain of 10 then the output will be 10 volts. As the RL (load) varies say from 8ohm to 4ohm the out voltage will remain at 10 volts so the current must vary to matain that 10 volts. A constant current source will the same except the current will be constant and the voltage must vary to maintain the current value. It is my understanding the BA3 is a constant voltage source amp. So the average power delivered to the load is E time I at this point on we the voltage and current will RMS values only and peak voltages and current. Power average = Po,so Po= Vrms squared divided by RL(r load), and Vo(peak rms)=sqare root of Po times RL. Po=I squared times RL, so Irms out = square root of Podivided by RL. So if we have amp with Po = 100watts into 8 ohm resistive load at some frequency sa 1 KHZ then Vo (rms peak)=square root of 100times 8 or 28.28 RMS volts peak or 56.57 peak to peak rms. the current into the 8 ohm load will be 3.54 amps rms. Now if we change the load to 4 ohms the voltage will remain the same 28.28 volts rms peak, so Po=28.28 squared divided by 4 =799.76 divided by4 is 199.94 watts. the current will be 7.2 amps rms.
I hope this will generate some discussion and questions on power amps
Part 2 Will follow on my understanding of BA3 and BA3 balanced.
I hope this will generate some discussion and questions on power amps
Part 2 Will follow on my understanding of BA3 and BA3 balanced.
It appears to me there is some confusion on audio power amps. I will attempt to explain my understanding as a part 1 then have a part 2 on Ba3 and Ba 3 balanced amps. Hopefully this will generate some discussion and understanding. Please DO NOT tell me I don't know what I am talking about, while this may be true let's discuss the issue and come to agreement without flaming someone. Also I am a two finger typist so please excuse mistyping and or spelling.
Part 1 For the following discussion this is a very simplified version of voltages and current, and assumes the load is pure resistive and not reactive. Voltage for audio is basically a sine wave.
Peak to Peak the total positive and negative swing (sine wave) around a reference point. Ideally for loud speakers it has no dc component.
Peak voltage The peak value either positive or negative around the reference point (as described above). This will be a peak voltage for 1/2 single cycle sine wave.
RMS voltage is used as measure of how much work can be done by the A-C voltage.
I often use peak to peak (PP) as that’s what my scope displays. Current (I) have similar values as the voltage that is I peak to peak, I peak and I RMS.
Now let's use peak voltage and peak current and convert to RMS values by the following: peak voltage = Vo, RMS voltage=Vrms, so Vrms=Vo divided by square root of 2.
Peak current =Io, and rms current = Irms, so Irms =Io divided by square root of 2.
Average Power is equal to Vrms times Irms. Understand this is a simplified discussion of voltage and current with respect audio power amps as we are making the assumption that the load RL is resistive only and not reactive at different frequencies. This is one reason we would like to have the output impedance of the amp to be low ideally zero.
There are basically two types of Audio power amps 1. Constant voltage source and 2. Constant current source.
A constant voltage source will maintain a constant voltage for a given input dependent upon the gain of the amp into a varying resistive load. (Remember we are only talking about very simple resistive loads not reactive loads).
As an example, assume we have 1 volt input with a gain of 10 then the output will be 10 volts. As the RL (load) varies say from 8 ohm to 4 ohm the output voltage will remain at 10 volts so the current must vary to matain that 10 volts.
A constant current source will behave the same except the current will be constant and the voltage must vary to maintain the constant current value.
It is my understanding the BA3 is a constant voltage source amp. So the average power delivered to the load is E times I. From this point on we will discuss the voltage and current as RMS values only and then convert to peak voltages and current if required.
Power average = Po,and Po= Vrms squared divided by RL(r load).
Vo(peak rms)=square root of Po times RL.
Po=I squared times RL, and Irms out = square root of Po divided by RL.
So if we have amp with Po = 100 watts into 8 ohm resistive load at frequency of 1 KHZ then Vo (rms peak)=square root of 100 times 8 or 28.28 RMS volts peak or 56.57 peak to peak rms.
The current into the 8 ohm load will be 3.54 amps RMS.
Now if we change the load to 4 ohms the voltage will remain the same 28.28 volts rms peak, so Po=28.28 squared =799.76 divided by 4 is 199.94 watts. The current will be 7.2 amps rms.
I hope this will generate some discussion and questions on power amps
Part 2 Will follow on my understanding of BA3 and BA3 balanced.
Part 1 For the following discussion this is a very simplified version of voltages and current, and assumes the load is pure resistive and not reactive. Voltage for audio is basically a sine wave.
Peak to Peak the total positive and negative swing (sine wave) around a reference point. Ideally for loud speakers it has no dc component.
Peak voltage The peak value either positive or negative around the reference point (as described above). This will be a peak voltage for 1/2 single cycle sine wave.
RMS voltage is used as measure of how much work can be done by the A-C voltage.
I often use peak to peak (PP) as that’s what my scope displays. Current (I) have similar values as the voltage that is I peak to peak, I peak and I RMS.
Now let's use peak voltage and peak current and convert to RMS values by the following: peak voltage = Vo, RMS voltage=Vrms, so Vrms=Vo divided by square root of 2.
Peak current =Io, and rms current = Irms, so Irms =Io divided by square root of 2.
Average Power is equal to Vrms times Irms. Understand this is a simplified discussion of voltage and current with respect audio power amps as we are making the assumption that the load RL is resistive only and not reactive at different frequencies. This is one reason we would like to have the output impedance of the amp to be low ideally zero.
There are basically two types of Audio power amps 1. Constant voltage source and 2. Constant current source.
A constant voltage source will maintain a constant voltage for a given input dependent upon the gain of the amp into a varying resistive load. (Remember we are only talking about very simple resistive loads not reactive loads).
As an example, assume we have 1 volt input with a gain of 10 then the output will be 10 volts. As the RL (load) varies say from 8 ohm to 4 ohm the output voltage will remain at 10 volts so the current must vary to matain that 10 volts.
A constant current source will behave the same except the current will be constant and the voltage must vary to maintain the constant current value.
It is my understanding the BA3 is a constant voltage source amp. So the average power delivered to the load is E times I. From this point on we will discuss the voltage and current as RMS values only and then convert to peak voltages and current if required.
Power average = Po,and Po= Vrms squared divided by RL(r load).
Vo(peak rms)=square root of Po times RL.
Po=I squared times RL, and Irms out = square root of Po divided by RL.
So if we have amp with Po = 100 watts into 8 ohm resistive load at frequency of 1 KHZ then Vo (rms peak)=square root of 100 times 8 or 28.28 RMS volts peak or 56.57 peak to peak rms.
The current into the 8 ohm load will be 3.54 amps RMS.
Now if we change the load to 4 ohms the voltage will remain the same 28.28 volts rms peak, so Po=28.28 squared =799.76 divided by 4 is 199.94 watts. The current will be 7.2 amps rms.
I hope this will generate some discussion and questions on power amps
Part 2 Will follow on my understanding of BA3 and BA3 balanced.
Assuming 4 volt losses off the rails, +/-36V pk which is about 80 watts rms
into 8 ohms.