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Old 6th January 2013, 07:00 PM   #821
N Brock is offline N Brock  United States
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Quote:
Originally Posted by AudioSan View Post
aha. your high rail voltage meens no current draw. messure voltage between P-ch source resistor and Gnd. and between N-ch source resistor and Gnd. just to make sure ypu have power to the output boards.
N-ch: -35.90 V

P-ch: 35.92 V
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Old 6th January 2013, 07:17 PM   #822
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and it is no way to adjust P1 and 2 to get some readings over source resistors? it is over them you want that 400+mV
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Old 6th January 2013, 07:56 PM   #823
N Brock is offline N Brock  United States
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Quote:
Originally Posted by AudioSan View Post
and it is no way to adjust P1 and 2 to get some readings over source resistors? it is over them you want that 400+mV
I twiddled some knobs, and got some voltage across them

Problem is I'm at the limit of the pots and have 150mV across the n-ch source resistors and 145mV across the p-ch

I remeber in the stock F5 thread some people had to add an extra resitor to get more range out of their pots...

I'm using IRF parts if that makes a difference.
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Old 6th January 2013, 08:00 PM   #824
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that is correct. yes. add more resistance on R5 and R6
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Old 6th January 2013, 08:13 PM   #825
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N brock,
Add exact schematic as reference.

What is value across R5,R6
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Last edited by buzzforb; 6th January 2013 at 08:16 PM.
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Old 6th January 2013, 09:27 PM   #826
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buzzforb. do you use 1K for R5/R6?
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Old 6th January 2013, 09:31 PM   #827
N Brock is offline N Brock  United States
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Quote:
Originally Posted by buzzforb View Post
N brock,
Add exact schematic as reference.

What is value across R5,R6
Schematic is the same as the Pass article for v2 with slightly higher rails.

I used 1k for R5 and R6. They measure about 800 ohms with the pots all the way up.
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Old 6th January 2013, 09:39 PM   #828
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I use 1k but had Jfets in 10ma range. Nbrock, I will need power on readings across those two resistors.

Couple questions.

What rail voltage? Did you used cascaded front end?
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Old 6th January 2013, 09:40 PM   #829
Renron is offline Renron  United States
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I've done a search, read quite a few posts but have not quite seen this question addressed.
Is there any advantage to using 3 pairs of Mosfet output devices per channel rather than the standard 2 Pair when building a V2? w/32V rails.
Less bias per device = cooler sinks? Tea-Bag eluded to this in his earlier post.
Sonics better or worse?
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Old 6th January 2013, 09:46 PM   #830
N Brock is offline N Brock  United States
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Quote:
Originally Posted by buzzforb View Post
I use 1k but had Jfets in 10ma range. Nbrock, I will need power on readings across those two resistors.

Couple questions.

What rail voltage? Did you used cascaded front end?
R5 has 4.22 volts across it. R6 has 4.55 V.

34 volt rails. No cascade going on.

I really appreciate the effort.
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