Too low impedance at some frequencies


I have a question that what will happen if the solid state amplifiers designed to drive 4-8 Ohms speakers face with 2 Ohms load at some frequencies?

I'm building crossover networks, second-order low-pass filters, for my 4 Ohms subwoofers. Basically, I tried to simulate the results on simulator with the component values I already have; 3.3mH and 390uF pairs. The result is crossover point of 150Hz with Chevbychev alignment (+3dB at 150Hz).

However, the impedance curve fell down to 2 Ohms at 150 Hz, as depicted on attached. So, will any dangers happen to the amplifier?


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What amplifiers are you using?
This seems to be the easiest way to answer your question.
Some hold up under that load, but not many consumer amps made for the living room would like it.

Did you wire these 2 woofers in parallel to become this heavy load?

You can also use a bit higher induction like 4 or 5 mH, and a bit lower capacitance and redo the simulation with those values.

Does that help?
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What amplifiers are you using?
I use Braun Atelier A1 integrated amplifier.
Did you wire these 2 woofers in parallel to become this heavy load?
No, there is only single subwoofer per side and also with lowpass filter for each sub.

The load curve on attached picture was the simulation result of a 4-Ohm subwoofer with a lowpass filter (2nd order; 33mH and 390uF).
low frequency not a good idea.
Not sure if I found the right A1 but it is listed at 8 ohms 50 watts
not even sure if it can do 4 ohms. 2 ohms no way

do you have a datasheet or TS specs for the subs.
What speaker is this? we can get a actual impedance curve
see what is really happening.
Well cool, that is not enough data to do anything.

Well ...guess its a 4 ohm sub
basically gonna be close to Re anyways at 250 Hz

so 3.8 to 4 ohms.

About all your gonna get with a 3.3 mH coil
because making the cap larger will change the impedance curve.
to dip way to low
close to a short.

Anyways 3.3 mH needs 82 to 100u
that is it, any larger cap value is dangerous.

to go lower you need 6.8 mH
same thing only 82 to 100u

or the impedance gets dangerous.
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