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Phil Allison[_4_] Phil Allison[_4_] is offline
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Default Input transformer for Spectra Sonics 101 preamp

wrote:

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** Bull****, it ain't the same card.

An input tranny that gave 10dB more gain would reduce the impedance
to 60 ohms. Way to low for any modern mic.


You won't take no for an answer - will you ?


**------------------------------------


10dB effective gain would require a 3.33:1 turns ratio



** 10dB = 10^0.5 = 3.16


which would reduce the Z from 600 to about 180 Ohms.



** Absurd since impedance varies with the SQUARE of the turns ratio.

Plus defies "conservation of energy" as +10dB is a 10 times power
increase so the same voltage must be fed into a load resistance 10 times lower.

From 600 to 60 ohm.


..... Phil