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Old 16th April 2003, 03:11 PM   #11
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Default I will probably go for it this year

Thanks for your good comments.
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Old 16th April 2003, 06:13 PM   #12
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Default I see capacitors everywhere...

Keep in mind that each stage has an AC current loop. The input stage has 4 capacitors (counting caps and bypasses caps as one) in the singnal path between the input and the interstage transformer. You have 2 cathode bypass caps and 2 power supply to ground caps.

In the output stage you have 2 caps/bypasses referencing the secondarys of the interstages to ground plus the final caps in the power supply.

All the numbers above are per channel.
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Old 21st April 2003, 01:10 PM   #13
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Default Cap in signal path

I thought that the bad capacitors, the ones that can damage music, were tha cap in series directly in the signal path. The cap you mentionned are in parallel. Any comments?
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Old 21st April 2003, 02:34 PM   #14
Norbert is offline Norbert  Europe
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Default Some Thoughts ...


if I'm writing about no capacitors in the signal path I mean coupling capacitors.
Of course all capacitors in the power supply and decoupling capacitors are also included in the signal path.
The goal for these capacitors is to achieve a low or at least a uniformly constistent impedance over the frequency range.
It depends how you look at things ...
The reason why this unusual combination of MOSFET driver and bipolar power transistors has been chosen is to achieve a high input impedance with a very low input capacitance (compare 2SK213 vs. 2SK 1058) and a very low output impedance which can only be achieved with bipolars if you want to avoid paralleling.

Best regards,

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Old 21st April 2003, 05:02 PM   #15
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Default How your amp does sound?

Hi SIr. Thanks for answering. Since you desing the amp in question can you comment on its sound?


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Old 21st April 2003, 09:58 PM   #16
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Why do you guys critisize the fact that this project uses a few caps?

Does anyone hold a supercircuit with no caps at all?

Get real folks...please?

FWIW, I thank mister Norbert Bayer for lettings have all his hard work.

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Old 21st April 2003, 10:24 PM   #17
JoeBob is offline JoeBob  Canada
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fregrove's right, a cap is used for certain reasons. Why build something without caps? Why not build something without transistors and tubes? Hell, let's omit the resistors too, then it'd be alot better!

Without cathode bypass capacitors you'd get local negative feedback and have a lower gain, some people swear against negative feedback, some people swear against capacitors. Everything is a compromise. But in the end all that matters is if it sounds good. So I say give it a try...
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