Understanding tube values

FrankD77

Groupie
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30
Probably a dumb question but here it goes ;)

I bought a bias adjuster and one of my amps needs to be adjusted to 35ma

I ordered matched tubes and one set has 44 and one set 45 written on the box.

When i adjust to 35 what does a higher value mean in practice ?

Sorry if it's a dumb question. I've been playing tube amps "forever" but diving a bit more into the basics.
 
Those values are probably the plate current that the vendor measured with their tube tester to match the tubes.

I like to reference Rob Robinette’s pages as a quick reference for tube biasing. It might be an easier read than the Aiken Amps pages.

You can use the bias calculator page to calculate the bias current if you input the tube type, plate voltage, and you have a target dissipation in mind for the amp class.

https://robrobinette.com/How_to_Bias_a_Tube_Amp.htm
https://robrobinette.com/Tube_Bias_Calculator.htm
 
Those values are probably the plate current that the vendor measured with their tube tester to match the tubes.

I like to reference Rob Robinette’s pages as a quick reference for tube biasing. It might be an easier read than the Aiken Amps pages.

You can use the bias calculator page to calculate the bias current if you input the tube type, plate voltage, and you have a target dissipation in mind for the amp class.

https://robrobinette.com/How_to_Bias_a_Tube_Amp.htm
https://robrobinette.com/Tube_Bias_Calculator.htm
Thanks for the links and info

I bought a bias tester with probes to make it a bit easier for myself.
great info in the links it's always good to know what happens.
 
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