The Sonus Faber Cremona Auditor is a fairly well known speaker using good quality drivers in a beautiful box. A client brought in a pair that he was not happy with, requesting an active crossover design. This is a speaker that measures quite well in terms of dispersion but it's not a speaker that handles higher levels very well. At moderately loud levels it sounds strained, most likely due to the use of a first order crossover with a ring radiator tweeter which is not ideally suited for a situation such as this which places heavy demands.
Raw response with the tweeter response raised for clarity: In reality they overlap each other.
No obvious breakup peaks are evident here.
The raw response of the woofer (green) shows a rise in the region from 700 Hz - 2.5k. This is eliminated with EQ (blue) and then a low pass filter is added.
This isn't shown here but I use a shelving filter to adjust the treble balance. This allows for a lot of adjustment later without messing up the crossover.
This is just a quick snapshot and not the entire battery of measurements that were taken and analysed.
Even a brief listen reveals an obvious improvement in the sound. The speaker is now entirely free of problems with a forward and strained sound.