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Thoughts on a McMurdo Silver Masterpiece VI Speaker
#33

I found my Masterpiece VI schematic, and it tells me that the voltage going in to the 680 ohm section of the speaker field is 430 VDC, and 332 VDC on the other end, so the 680 ohm field drops 98 volts. Using Ohm's law, I = E / R, the MP VI will have just over 144 mA of current flowing here - more than Leigh's solid-state filter choke can handle, which is as I expected.

I'll have to either go ahead and use a resistor, or possibly explore an alternative design for a high-voltage, high current regulator. (Any and all ideas on this subject are most welcome.)

But there's no hurry at this point.

My next move is to see if I have enough cloth-covered wire to make a speaker wiring harness to run from the coaxial speaker to the extra box I am going to have, which will contain the 2-way crossover, the audio output transformer, and either a power resistor or voltage regulator to replace the 680 ohm field. I also need to disassemble that nice new coaxial speaker and add some threadlock, then reassemble.

--
Ron Ramirez
Ferdinand IN


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RE: Thoughts on a McMurdo Silver Masterpiece VI Speaker - by Ron Ramirez - 03-01-2013, 08:17 PM



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