I never used a battery in the cathode circuit. I do not like Ni Cad batteries, personal preference. but if you want 1.2V, nicad works.
I only ever used Alkaline, and Lithium Ion cells. They do not like to be charged. Put them in series with the grid stopper resistor.
The only time there is a minuscule charging, it is when you draw grid current, so turn the volume down. That grid current is much lower than cathode current, cathode current on the average is much larger, and is there all the time. grid current only occurs for brief time, at each signal crest when the volume control is too high. That signal level makes it sound louder, it also makes it sound distorted. Do you like distortion?
I never heard any noise that came from Alkaline and from Lithium Ion batteries.
I only used them in power amplifiers, in input, driver, phase splitter, and output stages.
Noise, . . . what noise? Even a resistor with no DC current is -174dBm/Hz. And there is 20kHz of bandwidth, 20,000 times more than 1 Hz. Are you going to get rid of resistors?
I would not use battery bias for phono preamps. Different application, with much more sensitivity than a power amplifier input stage.
You experience may vary. My batteries lasted for several years, just like shelf life of the battery.
LEDs are not self bias, they are a special case of Fixed bias. think about that. The bias voltage is from the tube cathode current, and the cathode impedance is much larger than the LED impedance. The LED conrtols the bias, the tube does not control the bias.
Just my opinions.
$0.03 Adjusted for inflation.
I only ever used Alkaline, and Lithium Ion cells. They do not like to be charged. Put them in series with the grid stopper resistor.
The only time there is a minuscule charging, it is when you draw grid current, so turn the volume down. That grid current is much lower than cathode current, cathode current on the average is much larger, and is there all the time. grid current only occurs for brief time, at each signal crest when the volume control is too high. That signal level makes it sound louder, it also makes it sound distorted. Do you like distortion?
I never heard any noise that came from Alkaline and from Lithium Ion batteries.
I only used them in power amplifiers, in input, driver, phase splitter, and output stages.
Noise, . . . what noise? Even a resistor with no DC current is -174dBm/Hz. And there is 20kHz of bandwidth, 20,000 times more than 1 Hz. Are you going to get rid of resistors?
I would not use battery bias for phono preamps. Different application, with much more sensitivity than a power amplifier input stage.
You experience may vary. My batteries lasted for several years, just like shelf life of the battery.
LEDs are not self bias, they are a special case of Fixed bias. think about that. The bias voltage is from the tube cathode current, and the cathode impedance is much larger than the LED impedance. The LED conrtols the bias, the tube does not control the bias.
Just my opinions.
$0.03 Adjusted for inflation.
