In a 1.5 way speaker, how critical is the dcr of the inductor? A 4mH air coil 2ohms vs 1.2 ohms?
I was testing some different mH values and currently have a 3mH and 1mH in series, want to change to a 4mH with lower DCR.
Thoughts? It should raise the bass response a bit right with a lower DCR inductor??
I was testing some different mH values and currently have a 3mH and 1mH in series, want to change to a 4mH with lower DCR.
Thoughts? It should raise the bass response a bit right with a lower DCR inductor??
It won't make much difference, not enough to call it critical in any case. Try it if you like.. or try adding a few milliohms by a resistor just to see what the difference can be.
Very low DCR inductors are very important for tight, controlled, extended bass.
Believe it or not, a high DCR inductor can actually give you a rise in output, but only at
the bass resonant frequency of your speaker > not below or above. (sloppy & boomy)
For good bass, 2 ohms is just too high. Although pricey, I would always go .5 ohms or less.
CHEERS 🙂
Believe it or not, a high DCR inductor can actually give you a rise in output, but only at
the bass resonant frequency of your speaker > not below or above. (sloppy & boomy)
For good bass, 2 ohms is just too high. Although pricey, I would always go .5 ohms or less.
CHEERS 🙂
There is one thing I forgot to mention >
When you combine inductors to achieve a desired value, you must provide distance between them
because they interact. About 4cm is reasonable.
In your case, with a 3mH & 1mH > If you cable-tied them together, you would always end up with
a value above or below 4mH depending on 'wire/flux orientation'.
When you combine inductors to achieve a desired value, you must provide distance between them
because they interact. About 4cm is reasonable.
In your case, with a 3mH & 1mH > If you cable-tied them together, you would always end up with
a value above or below 4mH depending on 'wire/flux orientation'.
The DC resistance of coils can and should be incorporated in the loudspeaker and crossover design. Changes in the internal resistance of the power source by resistance of coils, transformers (tube amps) and other causes change the Qes value. The bass tuning should be corrected for that (if you’re picky). But in a normal domestic setting paying a lot of attention to bass tuning of the speaker itself mainly shows the negligence of the designer for the room influence.
Stacking or not stacking inductors on top of each other when combining them can be useful to produce more or less resistance per inductance as needed.
YES , there are lots of 'little tricks' that are very useful when joining inductors. I like the 'synergy' method of increasing inductance.
The reason I didn't mention it was to keep things simple. To indulge into this, you need to be able to measure inductance.
I actually recommend ALL enthusiasts to invest in a Multimeter that measures both L & C. They are not expensive 🙂
The other factor that reduces the difference is the 1.5 way. I've simmed no resistance against 2 ohms as a more extreme example.
First, the woofer on it's own showing the difference when increasing the resistance. The image to the right is when combined with the main woofer that doesn't change, and the variation is better than halved by this constant.
First, the woofer on it's own showing the difference when increasing the resistance. The image to the right is when combined with the main woofer that doesn't change, and the variation is better than halved by this constant.
A full range driver and another which is low passed at the baffle step.
Yes, the pictures above may not be clear. The first is an inductor crossover on just one woofer, with and without 2 ohms of resistance in the inductor, to show the regular effect of that much resistance.
The second is the same two when used at the same time as a fullrange is connected straight to the amp, and since the fullrange doesn't change it acts as a stabilising influence.
Yes, the pictures above may not be clear. The first is an inductor crossover on just one woofer, with and without 2 ohms of resistance in the inductor, to show the regular effect of that much resistance.
The second is the same two when used at the same time as a fullrange is connected straight to the amp, and since the fullrange doesn't change it acts as a stabilising influence.
Suppose you have an 8 Ohm rated woofer, and the voice coil DCR is 4 Ohms.
In that case, you have Either 4 Ohms + 2 Ohms = 6 Ohms.
Or 4 Ohms + 1.2 Ohms = 5.2 Ohms.
6/5.2 Ohms = 1.154
That is a change of 15.4%
(Not really a very large change) Right?
Suppose that same 8 Ohm rated woofer is in a closed box, and its impedance at resonance is 25 Ohms.
25 Ohms + 2 Ohms = 27 Ohms.
Or 25 Ohms + 1.2 Ohms = 26.2 Ohms
Compare
Or suppose that
same 8 Ohm rated woofer is in a ported box, and its impedance at both resonance frequencies is 25 Ohms.
25 Ohms + 2 Ohms = 27 Ohms.
Or 25 Ohms + 1.2 Ohms = 26.2 Ohms
Compare
4mH = 8 Ohms at 318 Hz.
What is your planned crossover frequency of the woofer that has a 4mH inductor?
What is the damping factor of your amplifier relative to 8 Ohms?
Consider the same factors for whatever your woofer impedance is.
The loudspeaker experts might worry, but I am not loosing any sleep over the 5.2 Ohms versus the 6 Ohms DCR sum.
In that case, you have Either 4 Ohms + 2 Ohms = 6 Ohms.
Or 4 Ohms + 1.2 Ohms = 5.2 Ohms.
6/5.2 Ohms = 1.154
That is a change of 15.4%
(Not really a very large change) Right?
Suppose that same 8 Ohm rated woofer is in a closed box, and its impedance at resonance is 25 Ohms.
25 Ohms + 2 Ohms = 27 Ohms.
Or 25 Ohms + 1.2 Ohms = 26.2 Ohms
Compare
Or suppose that
same 8 Ohm rated woofer is in a ported box, and its impedance at both resonance frequencies is 25 Ohms.
25 Ohms + 2 Ohms = 27 Ohms.
Or 25 Ohms + 1.2 Ohms = 26.2 Ohms
Compare
4mH = 8 Ohms at 318 Hz.
What is your planned crossover frequency of the woofer that has a 4mH inductor?
What is the damping factor of your amplifier relative to 8 Ohms?
Consider the same factors for whatever your woofer impedance is.
The loudspeaker experts might worry, but I am not loosing any sleep over the 5.2 Ohms versus the 6 Ohms DCR sum.
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Mister Audio,
How many woofers have you measured the DCR, and compared that number to the manufacturer's rated impedance?
A lot of '8 Ohm' woofers have DCR of 5 or 6 Ohms, but some have 4 Ohms DCR.
Just trying to get people to measure their loudspeakers; it seems that some never do that.
Just look at some speaker test reports in several magazines, you do not even need an Ohmmeter for that.
Manufacturers do what ever they want, when they specify either a woofer, or a complete loudspeaker system.
Magnapan?
Radial Strahler?
Etc., Etc.
Just Saying . . .
How many woofers have you measured the DCR, and compared that number to the manufacturer's rated impedance?
A lot of '8 Ohm' woofers have DCR of 5 or 6 Ohms, but some have 4 Ohms DCR.
Just trying to get people to measure their loudspeakers; it seems that some never do that.
Just look at some speaker test reports in several magazines, you do not even need an Ohmmeter for that.
Manufacturers do what ever they want, when they specify either a woofer, or a complete loudspeaker system.
Magnapan?
Radial Strahler?
Etc., Etc.
Just Saying . . .
DCR of the woofer voice coil + the DCR of the woofer crossover inductor = The total DCR of the loudspeaker.
Loudspeaker minimum impedance at some frequency (or frequencies) is equal to, or slightly more than the total DCR of the loudspeaker.
A simple Ohmmeter test will tell you something that some loudspeaker manufacturers will not tell you.
Use the idea, or toss it, your call.
Loudspeaker minimum impedance at some frequency (or frequencies) is equal to, or slightly more than the total DCR of the loudspeaker.
A simple Ohmmeter test will tell you something that some loudspeaker manufacturers will not tell you.
Use the idea, or toss it, your call.
I agree 100% I always use Jantzen P core with a large awg on my low pass filters. I know people always like to say well saturation but my drivers are usually always super efficient so it's nothing to worry about. I remember the first time I heard a woofer with no crossover so no resistance it was a woofer i am very familiar with and the difference is defiantly very audible resistance in crossovers for bass is bad no resistance much better.