I know my target for two tubes is 2500V800ma for full output. I have to say I am not that concerned about being able to drive each tube to it's limit. What I am trying to figure out is how much no load voltage I need to arrive at 2500V@800ma. The reason I say this is because under no load conditions the voltage I chose for my filter caps will determine my final voltage. Voltage is X 10 value of filter caps capacitance is 1/10 that of caps. So if I use 450V caps I will end up with 4500V if I use 250V caps I get 2500V and so on.......
So if I end up having more voltage then I truly need was wondering if it was easier to add more tubes sense you cannot find computer grade caps in a vary wide range of values. I am thinking 250,350,450 are the over-whelming norms. Since I have 7x GI7BT tubes it is fairly simple for me to add more tubes to get things to work out well. Origanaly my plan was to build the amp with 2 tubes. Generally I take a dim view on using more then two of any tube. Past that I would normally prefer to go to a larger tube if I want more power. In this case though if their is a way to predict voltage sage under load I can use the number of tubes to balance out the available caps. So in spite of my not wanting to build an amp with more then two tubes if it solves my problem would be willing to go as large as a 3-4 tubes if it solves the problem.
I do not want to have to deal with 4500V's if I only need 2500V since any thing I do to lower that would generate more no productive heat. It is one thing to generate heat as a by product of work that is goal oriented it is another to generate heat just trying to limit voltage.
So if I end up having more voltage then I truly need was wondering if it was easier to add more tubes sense you cannot find computer grade caps in a vary wide range of values. I am thinking 250,350,450 are the over-whelming norms. Since I have 7x GI7BT tubes it is fairly simple for me to add more tubes to get things to work out well. Origanaly my plan was to build the amp with 2 tubes. Generally I take a dim view on using more then two of any tube. Past that I would normally prefer to go to a larger tube if I want more power. In this case though if their is a way to predict voltage sage under load I can use the number of tubes to balance out the available caps. So in spite of my not wanting to build an amp with more then two tubes if it solves my problem would be willing to go as large as a 3-4 tubes if it solves the problem.
I do not want to have to deal with 4500V's if I only need 2500V since any thing I do to lower that would generate more no productive heat. It is one thing to generate heat as a by product of work that is goal oriented it is another to generate heat just trying to limit voltage.
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