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Old 29th April 2010, 09:39 PM   #3661
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Quote:
Originally Posted by massimo View Post
Not very good then......

1-0 (and a clear offside)

P.S. It's only a game and not serious staff like audio

Congratulations massimo, your Inter plays the final Europe Champions League, Forza Inter!!!!!

Now plays like your's Milito
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Old 30th April 2010, 11:45 AM   #3662
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Default Arrived the Vishay TX 2575 nude 0.01% & the BG 470uF/50V

Arrived the Vishay TX 2575 nude 0.01% & the BG 470uF/50V to upgrade Salas Phono RIAA, some pics for fun:

Click the image to open in full size.

Click the image to open in full size.
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Old 30th April 2010, 07:09 PM   #3663
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Question Adjusting gain between channels

I suppose that is with mine special R6 50 ohms trimmer instead the fixed resistor 27 ohms, I imagine that increasing/decreasing the voltage between Drain Q5 to Gnd can get the same gain in both channels?
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Old 30th April 2010, 09:11 PM   #3664
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First stage source resistor trimming is most influential for gain. Second stage for THD.
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Old 30th April 2010, 09:20 PM   #3665
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Drain Q2 to Gnd?
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Old 30th April 2010, 10:44 PM   #3666
Salas is offline Salas  Greece
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That is 2nd stage. You got it OK. If you want to play with gain you vary R2 slightly. That one drops more on R1 and ups gain or vice versa. Because the signal level is slight there, THD remains about the same. I don't recommend playing with 2nd stage for gain because it influences the total gain less drastically but changes THD by moving the bias point of the Q5 buffer. You may try optimize the distortion profile to your ears there, 10-11V Q2D-GND is where it measures best in general. Whatever you may like, stays matched between channels on second stage. First stage is much more suitable to balance out any total gain differences between channels. Takes output measurement capability when steady under mV signal is present on input somehow.
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Old 1st May 2010, 11:22 AM   #3667
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Hi Salas

Would you explain how to set the bias on the output buffer, depending on different psu voltages ?
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Old 1st May 2010, 12:12 PM   #3668
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Its already set by design. But jfet differences always hover around optimum if you got FFT to see THD or listen critically. The 2nd stage's drain voltage sets it. If you use a trimmer instead of a source resistance in second stage and play, don't exceed the buffer Jfet's Idss judging by the drop on its source resistor/value.
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Old 4th May 2010, 09:13 PM   #3669
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Vishay "nude" TX 2575 0.01% subjectively speaking are the best.
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Old 4th May 2010, 09:34 PM   #3670
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Where did you use those ?
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