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This Post Has Been Edited by the Author
In Reply to: RE: Determining the size of inter-stage coupling cap posted by EricSan on January 22, 2017 at 18:24:42
>>> also found Al's thread about replacing R10 with a choke that has the impact of changing R10 to 250k (http://www.audioasylum.com/cgi/vt.mpl?f=magnequest&m=11930). If I incorporate this change with a pair of nice NOS oil caps that measure 0.25uF, am I correct that this shifts the corner frequency to about 2.6Hz (and keeps phase shift below 26Hz)? <<<
Why does replacing R10 with a choke have the impact of changing R10 to 250k - damping resistor? I thought a significant benefit of using grid chokes was a dramatic reduction in the grid-to-ground resistance. Normally, other things being held constant, adding a grid choke will increase bass due to the resonant peak; increasing the coupling C can help manage the bass peak.
It has been a while since I looked at grid chokes - I could be way off.
Also consider, it is debatable whether the benefit of reducing phase shift below ~100 Hz provides justifies the trade-offs, for example: passing sub-bass frequencies.
Cheers,
91.
"Confusion of goals and perfection of means seems to characterise our age." Albert Einstein
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