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Old 26th May 2008, 06:01 AM   #131
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Absolute maximum Id is only 1mA.
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Old 26th May 2008, 06:31 AM   #132
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Have you finished college yet? Serious question.
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Old 26th May 2008, 06:31 AM   #133
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I don't quite understand why that is such a problem, it is not a power amplifier. It does have a relatively small transconductance but wouldn't linearity be of concern? I am thinking in terms of a source follower driving a bjt follower, as a buffer.
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Old 26th May 2008, 07:02 AM   #134
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Mr. Curl,
sonic degradation in paralleled (even if matched) devices occurs due to the effects of differences in signal processing. Another significant deteriorating factor is multiplied capacitances.
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Old 26th May 2008, 07:05 AM   #135
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Rt 50 ohm is quite typical load for MC. Often Ct 10n in parallel is added. Would there be any issue with JFET input capacitance??
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Old 26th May 2008, 08:23 AM   #136
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I have been producing world class pre-preamps for the last 35 years. Most here are rank amateurs, without experience, understanding, or even having done the computations necessary to determine what they are stating. I just can't cope with this disparity in understanding and experience. It is pointless. Also, 50 ohms is usually too low, 100-200 ohms is usually better with modern cartridges. Capacitance is optional and should point out the silliness of worrying about the intrinsic capacitance of the input devices.
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Old 26th May 2008, 08:36 AM   #137
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Just for the record, 100 ohm with such high as 10nF in parallel makes F(-3dB) = 159kHz.
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Old 26th May 2008, 08:44 AM   #138
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Quote:
Originally posted by Charles Hansen


But to me, this is so elementary that it's not worth wasting much time on. If your circuit has trouble driving the EQ network, then you shouldn't be designing circuits. There are much more subtle points to work on and achieve real improvements than to waste time on these types of basic problems that have been understood for decades.
So, which of the designs testet by audiophile didn't reflect the 'basic problems that have been understood for decades'?

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Rüdiger
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Old 26th May 2008, 08:50 AM   #139
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Quote:
Originally posted by PMA
to cover and switch
Is that a problemo ?
Moving coil stage on the left side of the picture. (RIAA is not on it)
The various combinations are PIC stored and push button selected, same-same for the MM stage on the right.
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Old 26th May 2008, 09:03 AM   #140
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I do not understand why you speak about problem. All I meant is I just made a proto to verify circuit function.
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