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Old 2nd October 2012, 10:45 AM   #8091
Salas is offline Salas  Greece
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How much second stage Miller is allowed for that graph?
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Old 2nd October 2012, 10:49 AM   #8092
vgeorge is online now vgeorge  Greece
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Thanks for the advise Ricardo.
I will listen as is for a while and do some tests later on.
Will let you know the outcome.
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Old 2nd October 2012, 12:23 PM   #8093
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Quote:
Originally Posted by Salas View Post
How much second stage Miller is allowed for that graph?
Based on my experience I used 900p
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Old 2nd October 2012, 12:38 PM   #8094
Salas is offline Salas  Greece
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Hmm he has V grade and 39Rs plus a rather sweet treble Japanese cart and 4m listening distance. We will learn if he will perceive and in what way by his report. He is surely in good balance already.
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Old 2nd October 2012, 12:48 PM   #8095
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Yes, I know you have been there so you know it is very good. The new 47k resistor difference is very small so it should not matter much.

Anyway the first graph looks way cool to me.

Maybe vgeorge wants to experiment... resistors in aligators are simple to use... we will learn from the outcome.
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Old 2nd October 2012, 12:57 PM   #8096
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There is always that wicked super fine tweak fixation lonely afternoon in times ahead...
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Old 2nd October 2012, 01:02 PM   #8097
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Hehe... I always keep some 10p caps around to clip someware during the night...
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Old 4th October 2012, 12:12 AM   #8098
Rush is offline Rush  United States
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Salas,

Now that my pre amp is complete. I am fretting over the output coupling cap used in this design. I want to use the best and a V-Cap TFTF seems to be the favorite, that I can't afford. You have a 2.2 uF cap but into a DCB1 with a 22k ohms pot it really should be a 4 uF cap.

Normally with a single ended supply like the Simplistic NJFET RIAA you have no choice but to cap couple the output.
But with my setup, I do have a -DC regulated supply available.

What would we be able to do? How about a DCB1 with a trimmer resistor in the lower leg?

Rush
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Old 4th October 2012, 05:32 AM   #8099
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2nd stage is sitting the buffer's gate at its VDS potential around 10V. So it centers there and carries it to the output. Now if the DC blocking could be transported to the buffer's input with a much lower value cap by using a 1-2meg gate to ground resistor for it, and there is a (-) adj supply available, we probably could make the output buffer like a DCB1 by matching the Jfets and the phono's (+) supply value available to the buffer after the RC at top right in simplistic's schematic. At least a quick thought. There are many highly regarded caps somewhat easier to pay for when the value is say 0.1uF or under. Maybe you would like a Jupiter as much or a Multicap RTX to give two opposite materials tech used between them examples. V-Caps I had put in a commercial phono that its owner bought for and asked me to fit, they did not impress me much for the money, still clean and smooth no doubt, could hear the upgrade. It had Hovland caps originally. Bigger upgrade was when I worked around the input circuit and tried a better suitable more linear tube type, cutting on noise also due to formerly excess gain. He adopted them after listening himself no matter how obsessed with his Telefunkens.
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Old 4th October 2012, 02:43 PM   #8100
Rush is offline Rush  United States
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Default V-Cap TFTF

Quote:
Originally Posted by Salas View Post
2nd stage is sitting the buffer's gate at its VDS potential around 10V. So it centers there and carries it to the output. Now if the DC blocking could be transported to the buffer's input with a much lower value cap by using a 1-2meg gate to ground resistor for it, and there is a (-) adj supply available, we probably could make the output buffer like a DCB1 by matching the Jfets and the phono's (+) supply value available to the buffer after the RC at top right in simplistic's schematic. At least a quick thought. There are many highly regarded caps somewhat easier to pay for when the value is say 0.1uF or under. Maybe you would like a Jupiter as much or a Multicap RTX to give two opposite materials tech used between them examples. V-Caps I had put in a commercial phono that its owner bought for and asked me to fit, they did not impress me much for the money, still clean and smooth no doubt, could hear the upgrade. It had Hovland caps originally. Bigger upgrade was when I worked around the input circuit and tried a better suitable more linear tube type, cutting on noise also due to formerly excess gain. He adopted them after listening himself no matter how obsessed with his Telefunkens.
The V-Caps need a bunch of time on them to sound their best.
See attached capacitor shoot out, if you haven't already.
Rush
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