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That is exactly why a choke is used instead of a resistor. A choke is a more expensive part, so why use it? The DCR is lower, so the tube biases to a higher plate voltage. The choke has impedance to AC signals, so when amplifying, the choke makes the plate voltage swing and delivers higher output in comparison to a resistor. So with a choke, the tube stage can deliver higher headroom.

The tube you are using could also have variability. Measure the voltages upstream of the choke and measure the voltages of the tube pins. Ohm's law can tell you a lot about what is happening (the schematic you posted above has the info necessary to calculate the choke DCR, R = V/I).
You'd like to know how many mA the tube is conducting along with the DCR of the choke. I'd be surprised if the Sowter DCR is far off from the originals, as it would mean the wire AWG or turns is different. I used chokes wound by CJ for a V76 build and posted some info here

<blockquote data-quote="dmp" data-source="post: 1193794" data-attributes="member: 40205">That is exactly why a choke is used instead of a resistor. A choke is a more expensive part, so why use it? The DCR is lower, so the tube biases to a higher plate voltage. The choke has impedance to AC signals, so when amplifying, the choke makes the plate voltage swing and delivers higher output in comparison to a resistor. So with a choke, the tube stage can deliver higher headroom. The tube you are using could also have variability.&nbsp; Measure the voltages upstream of the choke and measure the voltages of the tube pins. Ohm&#039;s law can tell you a lot about what is happening (the schematic you posted above has the info necessary to calculate the choke DCR, R = V/I). You&#039;d like to know how many mA the tube is conducting along with the DCR of the choke.&nbsp; I&#039;d be surprised if the Sowter DCR is far off from the originals, as it would mean the wire AWG or turns is different. I used chokes wound by CJ for a V76 build and posted <a href="https://groupdiy.com/threads/v76-tube-preamp-build.68498/#post-871716" target="_blank">some info here</a></blockquote>

[QUOTE="dmp, post: 1193794, member: 40205"] That is exactly why a choke is used instead of a resistor. A choke is a more expensive part, so why use it? The DCR is lower, so the tube biases to a higher plate voltage. The choke has impedance to AC signals, so when amplifying, the choke makes the plate voltage swing and delivers higher output in comparison to a resistor. So with a choke, the tube stage can deliver higher headroom. The tube you are using could also have variability. Measure the voltages upstream of the choke and measure the voltages of the tube pins. Ohm's law can tell you a lot about what is happening (the schematic you posted above has the info necessary to calculate the choke DCR, R = V/I). You'd like to know how many mA the tube is conducting along with the DCR of the choke. I'd be surprised if the Sowter DCR is far off from the originals, as it would mean the wire AWG or turns is different. I used chokes wound by CJ for a V76 build and posted [URL='https://groupdiy.com/threads/v76-tube-preamp-build.68498/#post-871716']some info here[/URL] [/QUOTE]

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