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RE: Poor Design for a Preamp

Posted by FlaCharlie on February 16, 2025 at 14:34:32:
"You can't drive into a 43 ohm load to ground with a stage that has a 8.3k output impedance. . . . 8.3k output wants to see a 83k load."

OK, so in the case of this 01A preamp, he could use a voltage divider with 68k in series and 22k to ground. This would reduce the voltage about the same as the 330k/100k combo he's using and it would present a load of 90k to the tube and be no problem.

The value of 68k || 22k is 16.62k. If we plug that into the low pass calculator then the -3db point would be 54.75k. That should also not be an issue, right?