L-pad vs series resistor

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Hi,
Why is it common to put the attenuation resistor (or L-pad) in series with the tweeter, rather than in series with the amplifier?

I would have thought that the best idea is to have the the resistor in series with the amp, so that
a) the tweeter is sees a low impedance source (the inductor) to dampen the resonance
b) the Xover filter sees the same impedance, regardess of the attenuation
c) any resistance is series with the resistor will cause the effect on the non-uniform impedance to be exaggerated. e.g. if the tweeter has a higher impedance at HF, the voltage at HF will be higher due to simple voltage-divider considerations, so the tweeter will no longer have a flat freq response.

Any comments on this to "correct" my understanding would be great!
 
AntM said:
Hi,
Why is it common to put the attenuation resistor (or L-pad) in series with the tweeter, rather than in series with the amplifier?

I would have thought that the best idea is to have the the resistor in series with the amp, so that
a) the tweeter is sees a low impedance source (the inductor) to dampen the resonance
b) the Xover filter sees the same impedance, regardess of the attenuation
c) any resistance is series with the resistor will cause the effect on the non-uniform impedance to be exaggerated. e.g. if the tweeter has a higher impedance at HF, the voltage at HF will be higher due to simple voltage-divider considerations, so the tweeter will no longer have a flat freq response.

Any comments on this to "correct" my understanding would be great!

Most drivers react based on the amount of current going though the VC, with this understanding you might have a different perspective.

Resistor only in series of the tweeter normally is to make the tweeter output less volume to make the effeciency compatible with other drivers.
 
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