doubt use RLC circuit

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Hello everyone. I open this thread to ask for help on a specific question. my loudspeakers are based on the design of Troels G. Jenzen ATS. Jenzen-ATS
I use a Hypex 501 amplification module to amplify the bass way. I have removed all the passive filter. my question is: does it make sense to keep the passive LCR circuit of the original passive filter if its function was to improve the impedance response of the AT wofer to facilitate the work of the Hypex? or what i say is silly?

BR

Toni
 
The parts inside the Orange cercle
 

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This appears to be the conjugate for the resonance impedance peak. It would not be changing the response unless the amplifier has a finite and noticeable output impedance, which the average audio amp doesn't. The scope of this filter is outside the normal cross so it works even when you remove the other components.

The question is, does it help?
 
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Not sure about that. It couldn't do much without the other components and even with the 6m8/0r12 in series, the 10 ohm version might cut a third of a dB.

Its tuned at 60Hz. The plot below showing earlier experimentation with the woofer shows the bass resonance is approximately there. In addition, the paragraph just below the schematic implies that it is there for the resonance impedance peak (as with the tweeter).
 

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you do not need these parts, there will be only additional heat created by it. The low output impedance of the amp shorts any effect.
It makes only sense with a passive xover where it compensates the rise in impedance influencing the other xover parts.

With the dsp amp you can do much more than with overpriced discrete parts in better quality, so that was a good choice
 
I thought one key advantage in an active crossover is to eliminate driver impedance and resonance from the equation. All you need to do is effect the correct transfer function at a line level.

Therefore the above impedance compensation circuit (using a whopping 22mH inductor) is redundant?
 
The RLC is a 110Hz acceptance filter.
I suspect there must have been a peak at that frequency so this filters it out somewhat.
It's at 61Hz as Allen stated and tuned to the second impedance peak of the bass driver. Normally the inductance plus the capacitive load of the impedance cause a resonance of some dB extra around 100Hz. The RLC deals with that. I have done so in a design about 10 years ago (it was noticeable...) and it's rather common practice when crossing over in the low hundreds. But there's no need with an active setup of course.
 
If you already have the RLC components, and don't have use for them, you can keep this Z-EQ circuit. Will make you feel better :)

Below is the impedance (for the bass only) with and without it - your call.
 

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Thank you very much to everyone for your help. I fundamentally read two types of answers that reflect the doubts I had. I must clarify that with the ecu of the Hypex amplification module I can correct the frequency response (see attached photos). so if the function of the LCR circuit is to correct the frequency response exclusively, effectively, I don't need it. however, as mentioned, if the LCR circuit corrected the impedance response of the AT loudspeakers, making the impedance curve flatter, my question was whether this circuit could benefit the Hypex doing its job with "less effort ”. I read quite a few answers that consider that the LCR circuit is not necessary for this last purpose.

BR

Toñi
 

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