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Old 12th June 2004, 04:35 PM   #1
Odysei is offline Odysei  Lithuania
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Default Input signal

How strong an input signal should be to make any of the Zen amps to do it's maximum amplification?

And another question.

What's the most common voltage of the input? How does it effect the sound?
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Old 12th June 2004, 06:38 PM   #2
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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.

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Old 13th June 2004, 03:33 AM   #3
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Typical Zen amp gain is 10 to 16 dB, so you'll need more than
that. In the 16 dB case, it takes about 1.5 Volts to get up
to 10 watts, but about 3 volts in the 10 dB case.

In all these amps, you can set the gain and input impedance
arbitrarily, but there are always tradeoffs in performance.
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Old 13th June 2004, 11:08 AM   #4
Odysei is offline Odysei  Lithuania
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So in order to get 30W at the output for example at the Penultimate Zen (ZV4) we need 3 Volts and 1 Amp at the input? So the amplifiers gain would be 10db?
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Old 13th June 2004, 02:21 PM   #5
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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
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Old 13th June 2004, 02:23 PM   #6
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I'm a man who likes a lady. Does that help?

Jan Didden
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Old 13th June 2004, 02:32 PM   #7
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Off-topic:

Ehem... You know? I'm a man who likes girls.

JH
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Old 13th June 2004, 02:37 PM   #8
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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.


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Old 14th June 2004, 05:49 AM   #9
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Quote:
Originally posted by Odysei
So in order to get 30W at the output for example at the Penultimate Zen (ZV4) we need 3 Volts and 1 Amp at the input? So the amplifiers gain would be 10db?
More Like 3 volts and 3 mA.
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Old 14th June 2004, 08:54 AM   #10
Odysei is offline Odysei  Lithuania
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But this can't be 3 Volts and 3mA, if we amplify 3mA 10db we'll get 30mA and if 16db that would be just 0.12 A . If we use stronger source let's say 3 Volts and 30 mA then we'll get at 10db 0.3A and at 16db 1.2A.

Am I right?
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