bluebird
Well-known member
So I've been playing around with the circuit attached. The problem with it can be seen in the frequency graph. The frequency range above the bell is boosted or cut a couple dB's along with the bell. Below the bell is fine. And its additive as you boost more frequencies.
I've replaced the tube with a regular inductor and it works as expected with the frequencies above the bell being flat.
I thought it might have to do with miller capacitance and tried it with a pentode but no different than the triode.
I've tried all different resistor values and capacitor values. tried shunting grid to ground, to plate, to cathode with small capacitance but it only seemed to make things worse.
Any tube guys out there understand how this works and have any ideas on how to bring that high end down?
Thanks!
I've replaced the tube with a regular inductor and it works as expected with the frequencies above the bell being flat.
I thought it might have to do with miller capacitance and tried it with a pentode but no different than the triode.
I've tried all different resistor values and capacitor values. tried shunting grid to ground, to plate, to cathode with small capacitance but it only seemed to make things worse.
Any tube guys out there understand how this works and have any ideas on how to bring that high end down?
Thanks!