Watts and power

Hey there @audiozenology

That dip in impedance is a factor of woofer electro-electromechanical properties and sometimes a 2.5/3.5 way folding in another driver. Crossover may shunt current from woofer to tame a peak.

The speakers in question were a pair I did a complete speaker and crossover analysis. I am confident of my conclusions. The impedance dip was deliberate and unnecessary. A simpler 3 way low pass would have duplicated the transfer function and raised the minimum impedance by 2 ohms.

However, in a lot of cases, your statement above would be true.

Define "read the most correctly". Are you am amplifier design/EE?
If you don't exceed the rated continuous or peak wattage at a given impedance, then you have enough current (and voltage).  Georgehifi is making assumptions about performance that are not supportable with the data on hand ... namely wattage at a given impedance. I won't claim a 1500 watt $500 amplifier is going to have the overall sonic performance of a high end class-A amplifier, even at 100W, but with a speaker that drop to 2 ohms (approx), an amplifier that can deliver 1500 watts at 2 ohms, is not going to sound "anemic" as long as you don't drive it into clipping.

Watts, or power, is equal to voltage multiplied by current. But an individual speaker may want more voltage at some frequencies, versus more current at other frequencies. And if your amplifier is limited in one of those dimensions, it will have trouble driving the speaker.

Oops, sorry meant to say:

simpler 3rd order low pass

Best,
E

erik_squires,

Did you look into resonances? It is not uncommon to use the "cross-over" to damp a resonance. Your assumption is that the cross-over designer was competent as well. Especially in boutique audio, my experience is that is often not the case. Thank you for the post. Always good to have a reasoned discussion.

Hi @audiozenology:

I did a complete speaker and crossover analysis.

This means I measured the impedance and FR of each driver in the near field to achieve quasi-anechoic measurements. I further took the crossover apart and simulated the entire speaker in XSim. I validated my simulation by matching the simulated frequency and impedance curves to actual.

I then compared the simulated original crossover to a simulated crossover using a more conventional approach. So when I write:

would have duplicated the transfer function

This means that the input of the crossover to the output of the crossover would have been the same given the measured driver impedance.

What you are describing is akin to notch filters. That’s not what was present, and if I had not taken this into account, the two transfer functions would have been different. Further, resonance filters typically appear at the top end of a driver’s range, not the bottom.

Best,

E