The amplification would not change with the input voltage (although there may be some compression).
If you calculate backwards, from the max output power and the load impedance you find the max output voltage. Alternatively, you can take the max output voltage to be the total supply voltage minus some 4-6V. This is the p-p output voltage. For instance, with 40V total supply, the p-p output will be around 34 V, which is 17V peak, which is about 12V rms. Divide that by the amp gain. Suppose the gain is 10, then you need 1.2V rms at the input to get max output power.
Jan Didden
If you calculate backwards, from the max output power and the load impedance you find the max output voltage. Alternatively, you can take the max output voltage to be the total supply voltage minus some 4-6V. This is the p-p output voltage. For instance, with 40V total supply, the p-p output will be around 34 V, which is 17V peak, which is about 12V rms. Divide that by the amp gain. Suppose the gain is 10, then you need 1.2V rms at the input to get max output power.
Jan Didden
My opinion:
If your source output impedence is equal to or lower than about 10% of ZV4 input impedence, you do not need 1 Amp at the input because your source could be reasonably assumed as a stiff voltage source.
By the way:
Jan Didden,
Are you a man looking like a lady or a lady talking like a man?
JH
If your source output impedence is equal to or lower than about 10% of ZV4 input impedence, you do not need 1 Amp at the input because your source could be reasonably assumed as a stiff voltage source.
By the way:
Jan Didden,
Are you a man looking like a lady or a lady talking like a man?
JH
Well, you know, you can't win them all. Keep trying!
BTW, You probably don't recognise the picture, but without this lady your internet connection would be much slower and primitive than it is. (Yes SY, this is a pointer to you!). If you talk about shakers and movers in internet land, she is one of the more influential. Looking deceptively ladylike, I know. Looks can be deceiving, both ways.
Jan Didden
BTW, You probably don't recognise the picture, but without this lady your internet connection would be much slower and primitive than it is. (Yes SY, this is a pointer to you!). If you talk about shakers and movers in internet land, she is one of the more influential. Looking deceptively ladylike, I know. Looks can be deceiving, both ways.
Jan Didden
those dB figures/ the gain everyone but you talks about here is voltage gain. The amplifier is a device with a fixed gain for voltage. For current it needs not really much to see at the input, and at the ouput it provides as much current as your speakers needs. (If your speakers isn´t very low impedance, in this case you don´t provide more input current but set a higher bias)
Thinking after some drink:
60W? The speakers want to shake the air violently so that they need energy transferring of as much as 60W. It means that there should be high current flow in the magnetic coil. Wow... is to be almost 4A peak. They might be a burden for the amp to be a pure class-A.
Off-topic complaint:
I don't know why the connection to diyAudio forum is so difficult these days? Is it kind of equivalent sin bin for me?
60W? The speakers want to shake the air violently so that they need energy transferring of as much as 60W. It means that there should be high current flow in the magnetic coil. Wow... is to be almost 4A peak. They might be a burden for the amp to be a pure class-A.
Off-topic complaint:
I don't know why the connection to diyAudio forum is so difficult these days? Is it kind of equivalent sin bin for me?
All possible:
I have to say, yes. Aleph 60 has the output peak current required for class-A operation with 60W power despite that the bias current is only about half of it when there is no input signal. (I don't mean that Aleph 60 is not a pure class-A amp, Nelson.)
Even greater than 60W of class-A operation is possible if we want it and if we are ready to welcome the high heat dissipation. I believe so.
But, I'm not ready to welcome that much of heat dissipation yet.
Off-topic:
Tonight, I did soldering to renew RC networks inside my amp, turned on the power switch, heard of the sound "beezzz, beezzz..." and saw smoke escaping around the bridge diodes... even though music was still playing... I did something wrong.
Probably, I need to live with a small radio at least one week... Or, I just buy the FirstWatt. Where is it now?
I have to say, yes. Aleph 60 has the output peak current required for class-A operation with 60W power despite that the bias current is only about half of it when there is no input signal. (I don't mean that Aleph 60 is not a pure class-A amp, Nelson.)
Even greater than 60W of class-A operation is possible if we want it and if we are ready to welcome the high heat dissipation. I believe so.
But, I'm not ready to welcome that much of heat dissipation yet.
Off-topic:
Tonight, I did soldering to renew RC networks inside my amp, turned on the power switch, heard of the sound "beezzz, beezzz..." and saw smoke escaping around the bridge diodes... even though music was still playing... I did something wrong.
Probably, I need to live with a small radio at least one week... Or, I just buy the FirstWatt. Where is it now?
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