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voltage divider with diode

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Show us. It's hard to tell what may be happening from your description.
 

bhuvanesh

Aug 29, 2013
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i have no schematics.what i want to know is if we want transfer maximum power to lead(loudspeaker)we have to match source resistance with load resistance.but speaker resistance changes with frequency.so i am recommended to use diode instead of resistor.but i dont know why.Thas my question
 

BobK

Jan 5, 2010
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A reasonable amplifier will have a source resistance of way less then 1 Ohm. You really do not want maximum transfer of power, or your speaker would be < 1 Ohm impedance. In fact, the ratio of the speaker impedance to the source impedance is called "damping factor" and higher is considered better, becuase a high damping factor suppresses the speaker resonance and contols the movement of the speaker better.

See here:

http://en.wikipedia.org/wiki/Damping_factor


Bob
 

Arouse1973

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Dec 18, 2013
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Bobs right. And a high damping factor is more important from a sound perspective at low frequencies which prevents boomy bass. The damping factor can also go down quite a bit with increasing frequency due to the reactive nature of the speaker.

Adam
 

(*steve*)

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Most audio amplifiers aim for zero output impedance and zero resistance in the leads.

This is NOT a case of wanting to match impedances.
 

KrisBlueNZ

Sadly passed away in 2015
Nov 28, 2011
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And to answer your question specifically, no, you never connect a diode in a speaker circuit. That will cause distortion (more or less, depending how you connect it). A diode will not compensate for the speaker resistance changing with frequency.
You may have misunderstood what you heard. If you can tell us exactly what you were told, we might be able to work out what was meant, and tell you whether it's right or not.
 
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