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For -4.8 dB (how did you figure that) you need to reduce the voltage across the speaker by about 40%. The value of resistor you put in series with the speaker will depend on the impedance of the tweeter. For an 8 ohm driver you need about a 5.3 ohm R and for 4 ohm half that much. The 5.6 Duelend would be -4.6dB for 8 ohms which should be close enough given the variations in speaker impedance with frequency.
I would experiment with some cheap resistors until you find a value you like before you spend the money for the expensive ones.
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For -4.8 dB (how did you figure that) you need to reduce the voltage across the speaker by about 40%. The value of resistor you put in series with the speaker will depend on the impedance of the tweeter. For an 8 ohm driver you need about a 5.3 ohm R and for 4 ohm half that much. The 5.6 Duelend would be -4.6dB for 8 ohms which should be close enough given the variations in speaker impedance with frequency.
I would experiment with some cheap resistors until you find a value you like before you spend the money for the expensive ones.
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