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Single Ended Triodes (SETs), the ultimate tube lovers dream.

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RE: Determining the size of inter-stage coupling cap

Posted by 91derlust on January 22, 2017 at 18:59:29:
>>> 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.
Remember also that other things being held constant, adding a grid choke will induce a resonant peak in the bass; increasing the coupling C can help manage the 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 justifies the trade-offs, for example: passing sub-bass frequencies.
Cheers,
91.