Hello. I have a silly question, as a result of having read that the low-pass inductor in a crossover does have an iron or ferrite core, as the current passed through it increases (by increasing the volume in the amplifier), there comes a point where is short-circuited.
Is that so? I ask because I have some B&W DM602 S1 speakers whose pso-low inducts have an iron core.
Greetings and thanks for responding.
Is that so? I ask because I have some B&W DM602 S1 speakers whose pso-low inducts have an iron core.
Greetings and thanks for responding.
Yes, they can saturate if enough current goes though them.
But large value air core inductors are impractical.
https://www.monolithicpower.com/en/how-to-avoid-inductor-saturation-in-your-power-supply-design
But large value air core inductors are impractical.
https://www.monolithicpower.com/en/how-to-avoid-inductor-saturation-in-your-power-supply-design
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So at high or not so high volumes, the inductor being shorted would cause unwanted frequencies to pass to the midwoofer? Is it as if it were connected directly without an inductor?
How did Bowers & Wilking put an iron core inductor in the DM602 S1? The S2 and S3 models already have air core inductors.
How did Bowers & Wilking put an iron core inductor in the DM602 S1? The S2 and S3 models already have air core inductors.
Electronic design is a balance of cost, performance, size, and availability.
Large value inductors are not available as air core.
Large value inductors are not available as air core.
Iron core inductors can saturate, but will not produce a short circuit.
Saturation can introduce some distortion of bass notes which would only become audible if the loudspeaker is played at above normal sound levels.
Air core inductors are more expensive than iron core inductors of the same inductance and resistance value, so are more likely to be used in high range speakers.
Saturation can introduce some distortion of bass notes which would only become audible if the loudspeaker is played at above normal sound levels.
Air core inductors are more expensive than iron core inductors of the same inductance and resistance value, so are more likely to be used in high range speakers.
So it would not justify changing the inductor of my speakers for the same value (1.2 mH) but with an air core.
In my opinion, it would not.
The air core replacement would not only have to have the same inductance value as the iron core, but also have the same DC resistance.
You cannot just substitute any old 1.2 mH air core inductor as it may upset the sound balance of the speaker.
The air core replacement would not only have to have the same inductance value as the iron core, but also have the same DC resistance.
You cannot just substitute any old 1.2 mH air core inductor as it may upset the sound balance of the speaker.
Smaller inductors can also get hot. It's not always obvious but I've unwound crossover inductors to find hidden heat damage. This can cause direct short circuits.
Other than that, the factors that determine the levels needed for saturation are not as straightforward as it can be looking at resistors to guess their heat dissipation. You also want to consider the amount the inductor is relying on the core to increase the value.
These two posts are an example of considering the dissipation..
https://www.diyaudio.com/community/threads/the-black-hole.349926/post-6864481
Other than that, the factors that determine the levels needed for saturation are not as straightforward as it can be looking at resistors to guess their heat dissipation. You also want to consider the amount the inductor is relying on the core to increase the value.
These two posts are an example of considering the dissipation..
https://www.diyaudio.com/community/threads/the-black-hole.349926/post-6864481