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Old 26th March 2006, 10:54 PM   #1
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Default double check the math

Hello Im building the attached amp in a mono mode and the B+ will be
300 v instead of 350. to keep the preamp voltages and currents the same I calculated the the 27K feed resistor to be now 3333 ohms
Does this seem kosher ?

Thanks Jeff
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Old 26th March 2006, 11:08 PM   #2
arnoldc is offline arnoldc  Philippines
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The voltage difference then is 350-293 = 57V, with 27000 dropping resistor, the current is 2mA.

Now you want to drop 7V (300-293) at 2mA, the resistor is 3500 ohms.

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Old 27th March 2006, 04:24 PM   #3
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Use switchmode caps for cathode decoupling stages...they make a worthwhile improvement in sound quality. Choose 105C low ESR types. Soundwise, I find them just as good a tants, esp for 1st stage.

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Old 27th March 2006, 04:48 PM   #4
Giaime is offline Giaime  Italy
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Originally posted by richwalters
Soundwise, I find them just as good a tants, esp for 1st stage.

Do you really like tants?
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