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previous: Major Pain I thought that was what you meant b... -- 11/18/2003 3:16 AM	View Thread

Re: Thanks Don

11/18/2003 11:30 AM
Rob Mercure	Re: Thanks Don MP, If you go the resistor route I suggest you separate the resistors that feed the output tubes from the preamp tubes. Most of your current draw is from the outputs and if one of these filaments opens all the other tubes will see much higher filament voltages with the reduced current through the resistors. If I use resistors to lower filament I size ones to feed the output tubes and separate ones to feed the preamp tubes - just a little Ohm's law and a bit more protection (then again, I often use NOS/UOS "vintage" tubes and want more filament protection). Rob

11/18/2003 11:30 AM

Rob Mercure
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Re: Thanks Don

MP,

If you go the resistor route I suggest you separate the resistors that feed the output tubes from the preamp tubes. Most of your current draw is from the outputs and if one of these filaments opens all the other tubes will see much higher filament voltages with the reduced current through the resistors. If I use resistors to lower filament I size ones to feed the output tubes and separate ones to feed the preamp tubes - just a little Ohm's law and a bit more protection (then again, I often use NOS/UOS "vintage" tubes and want more filament protection).

Rob

Replies:

Major Pain Re: -- 11/18/2003 8:03 PM